HYDROSILATION CURABLE COMPOSITIONS

BACKGROUND

Field

[0001] Electronic devices such as integrated circuits (IC), central processing units (CPU), and power modules typically generate a significant amount of heat during operation. To cool these devices, heat generated by the electronic device during use is transferred from a heat source of the device to a heat sink, where the heat is harmlessly dissipated.

[0002] Thermal interface materials, also known as TIM or TIMs, provide an intimate contact between the heat sink and the heat source to facilitate heat transfer between the two. TIMs impact device performance and reliability. These materials can be used to accelerate heat dissipation and provide a cost-effective method to reduce overall size of the package. TIMs can be based on metal, ceramics or polymer composites.

[0003] Thermal pastes, also called thermal greases or thermal compounds, are the most common TIMs. These one-component materials effectively bridge the gap between the heat source and heat sink, eliminate micro air pockets, and as a result, provide low thermal resistance initially. The biggest challenge with these materials, however, is migration and voiding over time, causing reduction in thermal conductivity as well as contamination in the surrounding areas.

[0004] Another type of TIMs are thermal pads, which are commonly pre-cured and pre-cut. Pads address the handling and application challenges of the pastes. In order to achieve effective heat transfer, the thermal pads should be designed to have Shore OO Hardness less than 90 to minimize the mechanical stress and to improve surface contact between heat components and thermal pads.

[0005] Reactive gap filler TIMs are cure-in-place materials, which are typically applied as a two-component paste which grows in molecular weight and cures into a solid pad. Compared to conventional pre-cured and pre-cut thermal pads, these gap fillers can adopt to the irregular surface terrain of the substrates, thus creating a more intimate contact without adding additional external pressure between the substrates. Traditional gap fillers are silicone-based since they provide good thermal conductivity and softness. However, there are issues with silicones including bleeding, which is mostly due to floating silicones, and outgassing which is mostly due to volatile cyclics. In particular, silicone-based materials are often associated with bleeding and outgassing due to low molecular weight cyclics, free/un reacted silicone chains, as well as decomposition during thermal aging. This often leads to device contaminations, as well as loss of intimate contact. A prior art silicone resin including a floating silicone is shown schematically in FIG. 1.

[0006] Thermal interface materials traditionally made with silicone and thermally conductive fillers are prone to outgas low molecular silicone species when in use at certain temperatures over time. These silicone species will in turn contaminate the electronics that they are in contact with, damaging them and affecting their performance.

[0007] Silicone-based TIM offers the high temperature resistance and low modulus of a silicone material and it has been widely used in industry. However, its use has been limited in applications such as LED or computer hard drive where silicone outgassing can be a problem affecting the optical clarity due to fogging or reducing the efficiency of heat transfer due to presence of volatiles.

[0008] Solutions on ways to eliminate the volatile species from silicone polymers have been attempted for many years. For example, a method to continuous devolatilization of silanol-term inated silicone polymer has been disclosed by Ashby on US Patent No. 4,096,160. According to this patent, an improved process for producing a substantially cyclic polysiloxane-free method is described.

[0009] US Patent No. 6,627,698 also describes a method of removing residual volatile siloxane oligomers from emulsions containing siloxane polymers.

CN 102719100A also discloses a preparation method of the low-volatile silicone rubber compound. However, still with the sophisticated manufacturing improvements to reduce the low molecular volatiles and cyclics in the silicone material, the concern of potential contamination still remains.

[0010] Other chemistries have been explored for thermal interface material applications. For example, US Patent Application Publication No. 2018/0171113 describes a thermally conductive resin composition based on acrylate resin, polybasic acid ester resin and thermal fillers used as a thermal grease.

[0011] JP505450 describes a thermally conductive molded product that does not generate volatile components. The thermally conductive molded product is formed of a polymer composition containing a thermally conductive filler, a non-silicone polymer as a substrate having an allyl group on its end, and a non-silicone oil. Polyisobutylene having allyl group is described; however, a substantial amount of oil is needed to address the high viscosity of the final mixture.

[0012] Polydimethylsiloxanes (PDMSs) have been used to make TIMs. However, a typical PDMS will bleed out and this is not good for TIMs. For example, bleeding can occur when: (1 ) unreacted material (such as unreacted high molecular weight material) bleeds to surrounding areas and contaminates components, such as electronic parts;

(2) when some silicone does not react resulting in floating silicones; and (3) when heat causes degradation of silicone components, which can then bleed.

[0013] There is a need for a gap filler type thermal interface material that delivers intimate initial contact with the heat components and low interface thermal resistance. It remains advantageous to provide a thermal interface material that minimizes volatile outgassing, bleeding and contamination while extending the life of the electronic devices.

SUMMARY

[0014] Compositions which meet the need for a gap filler type thermal interface material that delivers intimate initial contact with heat components and low interface thermal resistance are provided. The provided compositions advantageously provide a thermal interface material that minimizes or prevents volatile outgassing, bleeding and contamination while extending the life of devices, such as electronic devices such as batteries and optical devices. Reaction products and adducts of such compositions and methods for making the compositions are provided. Resins systems also are provided.

[0015] The provided compositions may be gap fillers. Generally, the compositions are two part, filled, liquid paste systems. However, one part compositions which are filled, liquid paste systems are also provided.

[0016] A composition comprising a silicone hybrid resin is provided. The silicone hybrid resin is prepared from two parts, and upon mixing the two parts, the silicone hybrid resin is cured. A thermally conductive filler or a plurality of thermally conductive fillers is/are added and dispersed throughout the silicone hybrid resin to provide thermal conductivity, which may be used as a TIM.

[0017] The silicone hybrid resin has a predominantly comb-like network structure, and may be formed by reacting a compound comprising one unsaturated olefin (the "comb") having vinyl and/or vinylidene located at the terminal end(s) or pendent on the compound and/or vinylene functionality terminal, pendent or internal of the main chain of the compound, the compound having an average molecular weight of at least about 100 up to about 10,000, a compound comprising at least two silicon hydride functional group (-SiH), a crosslinker component comprising at least two vinyl groups, and a hydrosilation catalyst. The comb-like network structure has a hydrido-silicone backbone. A side chain, comb portion of network structure (the "comb"), is formed from an unsaturated polyalphaolefin (uPAO) or other mono-unsaturated compounds.

Preferably, the compound comprising at least two silicon hydride functional group has a siloxane backbone. When an unsaturated polyalphaolefin (uPAO) is used to make the silicone hybrid resin, the silicone hybrid resin is a uPAO-silicone hybrid resin. A reaction scheme for a composition of the invention is shown in FIG. 2. For those skilled in the art, it is understandable that the final structure is idealized and other addition structure variations may exist.

[0018] As used herein, the term "comb" refers to a compound with at least one double bond having a long chain with molecular weight (MW) of at least about 100 up to about 10,000 daltons, and is the same as a "comb material" and a "comb compound." The comb is generally a small molecule. When the comb is a polymer, it has a number average molecular weight of about 500 up to about 10,000. The comb may be a compound including one unsaturated olefin having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound or, alternatively, the comb may be a vinylene compound including one or multiple internal double bonds -CH=CH-

[0019] It will be understood that where a compound comprising one unsaturated olefin having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound is disclosed for use in compositions, adducts, systems, methods and reactions herein, a compound comprising internal double bonds that are not vinylidene may alternatively be used. An example of a suitable compound comprising internal double bonds that are not vinylidene is vegetable oil. Methyl oleate (MW 296), which comes from renewable sources, may be used as the comb.

[0020] Suitable compounds comprising internal double bonds that are not vinylidene include vinylene compounds with one or multiple internal double bonds. Accordingly, a vinylene compound with one or multiple internal double bonds -CH=CH- may be used instead of the compound comprising one unsaturated olefin having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound as the comb material. Thus, a vinylene compound with one of more multiple internal double bonds -CH=CH- may be used with a compound comprising at least one silicon hydride functional group ("SiH compound") instead of using the compound comprising one unsaturated olefin having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound with the SiH compound. It also will be understood that a compound comprising one unsaturated olefin having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound as disclosed herein may include one or multiple internal double bonds -CH=CH-. The compound including one or multiple internal double bonds -CH=CH- may have an average molecular weight of at least about 100 up to about 10,000. An example of a vinylene compound comprising one internal double bond -CH=CH- for use in the compositions, adducts, systems, methods and reactions disclosed herein is methyl oleate (molecular weight (MW) 296), which has the double bond located in the middle of the chain. An example of a vinylene compound comprising one internal bond -CH=CH- for use in the compositions, adducts, systems, methods and reactions disclosed herein is an ether or ester derivative of crotyl alcohol (for example, crotyl octyl ether), which has the double bond located at the terminal end of the chain. An example of a compound having multiple internal double bonds for use in the compositions, adduct, systems, methods and reactions disclosed herein is high oleic soybean oil (molecular weight (MW) of about 880), which is a polyunsaturated triglyceride. Accordingly, the vinylene compound including one or more multiple internal double bonds-CH=CH- may come from a renewable resource, such as methyl oleate (MW 296) or high oleic soybean oil (MW of about 880). Other examples include palm oil, soybean oil, rapeseed/canola oils, linseed oil, castor oil, sunflower oil, to name just a few.

[0021] The silicone hybrid resin may be formed by combining two separate parts: Part A and Part B. At least one of Parts A and B comprise an uPAO. Desirably, Parts A and B each contain an uPAO. One of Parts A and B further comprises a compound comprising at least one silicon hydride functional group and the other of Parts A and B comprises a crosslinker component and a hydrosilation catalyst, which also is referred to as a hydrosilylation catalyst herein. Hydrosilation is the addition of Si-H bonds across unsaturated bonds. It is also called hydrosilylation. The terms hydrosilation catalyst and hydrosilylation catalyst are used interchangeably herein. When two separate parts are used, it is important to keep the compound comprising the silicon hydride functional group separate from the crosslinker component and the hydrosilation catalyst so that they do not react prematurely. Upon mixing the two parts, both parts react to form the comb-like structure. It is preferred that at least one of the Part A or Part B further comprises a thermally conductive filler or a plurality of thermally conductive fillers. Although the silicone hybrid resin is preferably formed from two parts, it also may be formed from a one part composition.

[0022] The inventive disclosure includes a curable composition comprising: a compound comprising one unsaturated olefin having vinyl or vinylidene or vinylene functionality, the compound having an average molecular weight of at least about 100 up to about 10,000, a compound comprising at least one silicon hydride functional group, a crosslinker component comprising at least two vinyl or vinylidene or vinylene groups, and a hydrosilation catalyst is provided. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising one unsaturated olefin. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising one unsaturated olefin. The curable composition may comprise a thermally conductive filler or a plurality of thermally conductive fillers and may be used as a TIM. The curable composition is useful for forming a silicone hybrid resin. In particular, the curable composition is useful for forming silicone hybrid thermal interface materials based on unsaturated polyalphaolefins (uPAOs).

[0023] The inventive disclosure includes an adduct of a compound having an average molecular weight of at least about 100 up to about 10,000 comprising at least one olefin having vinyl or vinylidene or vinylene functionality, a compound comprising at least one silicon hydride functional group, and at least one crosslinker group including at least two vinyl or vinylidene or vinylene functional groups, made in the presence of a hydrosilation catalyst is provided. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising at least one olefin. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising at least one olefin.

[0024] The inventive disclosure includes a reaction product comprising the product made from reacting a compound having an average molecular weight of at least about 100 up to about 10,000 comprising at least one olefin having vinyl or vinylidene or vinylene functionality, a compound comprising at least one silicon hydride functional group, at least one crosslinker group comprising at least two vinyl or vinylidene or vinylene functional groups and a hydrosilation catalyst is provided. Desirably, the product made is a silicone hybrid resin, and the reaction product desirably comprises the silicone hybrid resin. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising at least one olefin. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising at least one olefin.

[0025] The inventive disclosure includes a two-part composition comprising: (1 ) a first part comprising: (a) a compound comprising one unsaturated olefin having vinyl or vinylidene or vinylene functionality, said compound having an average molecular weight of at least about 100 up to about 10,000; (b) a crosslinker component comprising at least two vinyl or vinylidene or vinylene functional groups; and (c) a hydrosilation catalyst; and (2) a second part comprising a compound comprising one unsaturated olefin having vinyl or vinylidene or vinylene functionality, said compound having an average molecular weight of at least about 100 up to about 10,000. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising one unsaturated olefin which is in the first part. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising one unsaturated olefin which is in the first part. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising one unsaturated olefin which is in the second part. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising one unsaturated olefin which is in the second part.

[0026] The second part may optionally further comprise a compound comprising at least one silicon hydride functional group. The compound comprising at least one silicon hydride functional group may be used to balance the weight and stoichiometry. The two-part composition can be used to make a silicone hybrid resin.

[0027] The inventive disclosure includes also includes resin system comprising a compound having an average molecular weight of at least about 100 up to about 10,000 comprising at least one olefin having vinyl or vinylidene or vinylene functionality, a compound comprising at least one silicon hydride functional group, at least one crosslinker group comprising at least two vinyl or vinylidene or vinylene functional groups and a hydrosilation catalyst. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising at least one olefin. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising at least one olefin.

[0028] The inventive disclosure includes method of making a silicone hybrid resin comprising reacting a compound having an average molecular weight of at least about 100 up to about 10,000 comprising at least one olefin having vinyl or vinylidene or vinylene functionality I, a compound comprising at least one silicon hydride functional group, at least one crosslinker group comprising at least two vinyl or vinylidene or vinylene functional groups and a hydrosilation catalyst is provided. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising at least one olefin. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising at least one olefin.

[0029] Also provided is a method of making a uPAO-silicone hybrid resin including: (1 ) providing a first part including: (a) a compound comprising one unsaturated olefin having a vinyl or vinylidene or vinylene functionality, said compound having an average molecular weight of at least about 100 up to about 10,000; (b) a crosslinker component including at least two vinyl or vinylidene or vinylene functional groups; and (c) a hydrosilation catalyst; and (2) a second part including: (a) a compound including one unsaturated olefin having a vinyl or vinylidene or vinylene functionality, said compound having an average molecular weight of at least about 100 up to about 10,000; and (b) a compound including at least one silicon hydride functional group and mixing the first part and the second part to form a silicone hybrid resin. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound comprising one unsaturated olefin which is in the first part. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound comprising one unsaturated olefin which is in the first part. The vinyl or vinylidene functionality may be located at the terminal end(s) or pendent on the compound including one unsaturated olefin which is in the second part. The vinylene functionality can be terminal or pendent and can also be internal of the main chain of the compound including one unsaturated olefin which is in the second part. [0030] A hydrosilation curable composition is provided, which includes:

(1 ) a hydridosilicone;

(2) a mono-vinyl comb monomer having a molecular weight above 100, preferably above 200, selected from monovinyl silicone, unsaturated monofunctional olefins and monofunctional polyolefins, (meth)acrylates, alkenyl ethers, esters, and carbonates (e.g., allyl compounds, undecylenic acid ester, 3,3-dimethyl-4-vinyl pentanoate);

(3) a multifunctional vinyl monomer having at least two vinyl or vinylidene groups in one molecule; and

(4) a catalyst suitable for catalyzing hydrosilation reaction is provided.

[0031] A hydrosilation curable composition is provided which includes a hydridosilyl compound, a mono-vinyl compound having a molecular weight above 100, preferably above 200, a di-vinyl compound, a hydrosilation catalyst, and a thermally conductive filler is provided. This composition may be prepared from two parts to make a dispensable gap filler, or a gap pad thermal interface materials.

[0032] A resin system is provided which includes a hydridosilicone, an unsaturated alpha olefin dimer (uPAO) and a divinyl resin is provided. The resin system may further comprise a catalyst. The resin system is useful for forming a uPAO-silicone hybrid.

The hydridosilicone is the backbone for the uPAO-silicone hybrid and the uPAO is the comb. The divinyl resin is the crosslinker. Combining the hydridosilicone and the uPAO in the presence of the divinyl resin crosslinker and a catalyst results in the formation of the uPAO-silicone hybrid.

[0033] A device, such as an electronic device, containing a heat source, a heat sink and a TIM prepared with a silicone hybrid resin prepared according to the description described herein and disposed therebetween is provided. A device, such as an electronic device, containing a heat source, a heat sink and a TIM prepared with a curable composition according to the description described herein and disposed therebetween is provided. [0034] A product including a device, such as an electronic device, and disperse a curable composition as described herein, wherein the curable composition is a thermal interface material, is provided.

[0035] Also provided is a multifunctional vinyl monomer having at least two 3,3-di- methyl tri-pentanoate reactive groups.

[0036] An adduct of a multifunctional vinyl monomer having at least two 3,3-di- methyl tri-pentanoate reactive groups is provided as described herein.

[0037] A curable composition including:

(1 ) a multifunctional hydridosilyl compound; and

(2) a multifunctional vinyl or vinylidene monomer having at least two 3,3-di- methyl tri-pentanoate reactive groups is provided.

[0038] A reaction product including the product made from reacting (1 ) a multifunctional hydridosilyl compound; and (2) a multifunctional vinyl or vinylidene monomer having at least two 3,3-di-methyl tri-pentanoate reactive groups is provided.

[0039] A method for making a product including the steps of reacting (1 ) a multifunctional hydridosilyl compound; and (2) a multifunctional vinyl or vinylidene monomer having at least two 3,3-di-methyl tri-pentanoate reactive groups is provided.

[0040] A curable composition including a hydridosilyl compound, a di-functional 3,3- dimethyl-4-pentenoate, and a hydrosilation catalyst suitable for high temperature optical applications such as LED encapsulation is provided.

[0041] An optical device encapsulated with any of the compositions as described herein is provided.

[0042] A curable composition including:

(a) a compound comprising an unsaturated olefin comprising a main chain and one or more vinylene double bonds located in the middle of the main chain, said compound having an average molecular weight of at least about 100 up to about 10,000;

(b) a compound comprising at least one silicon hydride functional group; (c) a crosslinker component comprisinga vinyl, vinylidene or vinylene functional group; and

(d) a hydrosilation catalyst is provided. The crosslinker component may comprise at least two vinyl functional groups.

[0043] A curable composition including:

(a) a compound comprising an unsaturated olefin having a vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound, said compound having an average molecular weight of at least about 100 up to about 10,000;

(b) a compound comprising at least one silicon hydride functional group;

(c) a crosslinker component comprising at least one internal vinylene functionality; and

(d) a hydrosilation catalyst is provided.

[0044] A cured, filled thermal interface material (TIM) composition comprising:

(1 ) a cured composition made by curing a composition comprising:

(a) a compound comprising one unsaturated olefin having a vinyl or vinylidene or vinylene functionality, said compound having an average molecular weight of at least about 100 up to about 10,000;

(b) a compound comprising at least one silicon hydride functional group;

(c) a crosslinker component comprising a vinyl or vinylidene or vinylene functional group; and

(d) a hydrosilation catalyst; and

(2) a filler, wherein the cured, filled thermal interface material compostion has a Shore OO hardness of less than about 90 is provided. The compound comprising one unsaturated olefin may have vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound. The vinylene functionality of the compound comprising one unsaturated olefin can be terminal or pendent and can also be internal of the main chain of the compound comprising one unsaturated olefin. The crosslinker component can comprise at least two vinyl or vinylidene or vinylene groups.

BRIEF DESCRIPTION OF THE FIGURES

[0045] FIG. 1 is a schematic showing a floating silicone in a prior art resin made from silicone.

[0046] FIG. 2 shows the reaction scheme for a composition of the invention.

[0047] FIG. 3 shows a comb structure created by grating a compound including one unsaturated having vinyl functionality located at the terminal end(s) or pendent on the compound (mono-vinyl polydimethylsiloxane (PDMS)) to a compound including at least one silicon hydride functional group (methylhydridosiloxane-dimethylsiloxane copolymer).

[0048] FIG. 4 shows how LED devices encapsulated with an inventive composition showed no drop in relative light output for over 5000 hours.

[0049] FIG. 5A shows how an inventive composition described herein does not bleed after curing.

[0050] FIG. 5B and FIG. 5C each show how a commercial formulation bleeds after curing.

[0051] FIG. 6 shows how samples of outgassing were collected in headspace vials for a uPAO-silicone hybrid material prepared in accordance with the present invention and for a commercial formulation.

[0052] FIG. 7 is a rheology profile comparison (modulus and tan 6) of a uPAO- silicone hybrid prepared in accordance with the present invention and of a pure silicone system.

DETAILED DESCRIPTION

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the definitions set forth in this document will control. Preferred methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in practice or testing of the present disclosure. All publications, Application Publication applications, Application Publications and other references mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting.

[0054] As used in the specification and in the claims, the term "including" may include the embodiments "consisting of' and "consisting essentially of." The terms "comprise(s)," "include(s)," "having," "has," "can," "contain(s)," and variants thereof, as used herein, are intended to be open-ended transitional phrases, terms, or words that require the presence of the named ingredients/steps and permit the presence of other ingredients/steps. However, such description should be construed as also describing compositions or processes as "consisting of" and "consisting essentially of" the enumerated ingredients/steps, which allows the presence of only the named ingredients/steps, along with any impurities that might result therefrom, and excludes other ingredients/steps.

[0055] Numerical values in the specification and claims of this application, particularly as they relate to polymers or polymer compositions, reflect average values for a composition that may contain individual polymers of different characteristics. Furthermore, unless indicated to the contrary, the numerical values should be understood to include numerical values which are the same when reduced to the same number of significant figures and numerical values which differ from the stated value by less than the experimental error of conventional measurement technique of the type described in the present application to determine the value.

[0056] All ranges disclosed herein are inclusive of the recited endpoint and independently combinable (for example, the range of "from 2 to 10" is inclusive of the endpoints, 2 and 10, and all the intermediate values). The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value; they are sufficiently imprecise to include values approximating these ranges and/or values. As used herein, approximating language may be applied to modify any quantitative representation that may vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as "about," may not be limited to the precise value specified, in some cases. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. The modifier "about" should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression "from about 2 to about 4" also discloses the range "from 2 to 4." The term "about" may refer to plus or minus 10% of the indicated number. For example, "about 10%" may indicate a range of 9% to 11 %, and "about 1" may mean from 0.9-1.1. Other meanings of "about" may be apparent from the context, such as rounding off, so, for example "about 1" may also mean from 0.5 to 1.4.

[0057] As used herein, a resin, oligomer or monomers are used interchangeably here in the invention.

[0058] Acrylate is broadly defined as including acrylates, substituted acrylate, e.g., (meth)acrylates.

[0059] As used herein, the term "vinyl" (or ethenyl) refers to the functional group with the formula -CH=CH2. Accordingly, vinyl (or ethenyl) is the functional group with the formula -CH=CH2.

[0060] As used herein, the term "vinylidene" refers to compounds with the formula >C=CH2. where >, in >C=CH2. represents two identical or different hydrocarbon substituents. The substituents can be aliphatic or aromatic, and may contain unsaturation and/or heteroatoms. As used herein, the term, "vinylidene" includes terminal olefins such as those disclosed in US Application Publication Pub. No. 2019/0248936 A1 (ExxonMobil Chemical Application Publications, Inc.) and US Application Publication Pub. No. 2019/0359745 A1 (ExxonMobil Chemical Application Publications, Inc.), the entire contents of which are incorporated by reference herein. Suitable vinylidene compounds for use in the compositions, adducts, systems, methods and reactions disclosed herein include not only mPAOs, but also mono-methacrylates and multifunctional methacrylates. [0061] As used herein, the term "vinylene" refers to -CH=CH- As used herein, the term "internal vinylene group" means that the -CH=CH- is not a terminal group or pendent group but is part of the backbone of the compound comprising the vinylene, the -CH=CH-. Accordingly, as used herein, vinylene compounds comprise one or multiple internal double bonds -CH=CH-

[0062] The silicone hybrid resin may be formed by combining two parts having vinyl or vinylidene or vinylene and silcon hydride functionalites. When the silicone hybrid resin is formed form two parts, one or both parts comprises a compound having vinyl or vinylidene functionality located at the terminal end(s) or pendent on the compound or vinylene functionality terminal, pendent or internal of the main chain of the compound. One of those parts further comprises a compound comprising at least one silicon hydride functional group and the other part further comprises a crosslinker component and a hydrosilation catalyst. Typically, the compound including at least one silicon hydride functional group remain in a separate part from the crosslinker component and the hydrosilation catalyst until combined together to form the silicone hybrid resin.

[0063] It has been determined that the compositions of the present invention: (1 ) have negligible silicone resin; (2) have no leachable resin; (3) have a high dispensing rate; and (4) are thermally stable from about -40 °C to 80 °C. These are all advantages of the compositions of the present invention. In addition, the present invention provides for resins that can be made at lower cost than conventional silicone resins. In particular, the unsaturated polyalphaolefins (uPAOs) used in the compositions of the invention are lower cost alternatives to costly silicones which are conventionally used. Moreover, it has been found that by reacting PDMS with a uPAO as described herein, the bleeding which typically occurs with the use of PDMS can be avoided. The compositions of the present invention can thus advantageously provide for full crosslinking, high temperature resistance and no bleeding at lower cost than conventional compositions not made by reacting PDMS with a uPAO, making them particularly useful for use as TIMs in devices such as, for example, electronic devices such as batteries. [0064] The compositions, adducts, systems, methods and reactions of the present invention may include any suitable polyalphaolefin (PAO), produced by Chevron Phillips, ExxonMobil, INEOS, Lanxess, etc. The PAO can be saturated or unsaturated. Saturated PAOs are generally made through hydrogenation of unsaturated PAOs. As used herein, the term "PAO" is a general term and automatically includes uPAO. A compound for use in the compositions, adducts, systems, methods and reactions of the present invention may be a PAO which is saturated or unsaturated. When a saturated PAO is incorporated, it will not incorporate into the network structure but rather, behave as a plasticizer in the cured material.

[0065] The compositions, adducts, systems, methods and reactions of the present invention may include any suitable unsaturated polyalphaolefin (uPAO). A suitable uPAO is a compound comprising one unsaturated olefin having vinyl and/or vinylidene functionality located at the terminal end(s) or pendent on the compound and/or vinylene functionality terminal, pendent or in the main chain of the compound. Such a compound is hereinafter referred to as "unsaturated olefin compound" or as "unsaturated uPAO," which terms are used interchangeably herein. When an unsaturated PAO is used, it will be incorporated into the resin matrix through chemical reaction and bond formation. When the uPAO comprises vinylidene, the uPAO is a vinylidene PAO. Among all monofunctional PAO compounds having a C=C double bond of any kind, a monofunctional PAO for use in the compositions, systems, methods and reactions disclosed herein may have a lower limit of 10mol% vinylidene when the monofunctional PAO comprises vinylidene. The uPAO suitable for use in the compositions, adducts, systems, methods and reactions disclosed herein may be "high vinylidene uPAOs." When the uPAO is a high vinylidene uPAO, the uPAO will have over 50mol% vinylidene, more preferably over 80mol%, and still more preferably over 95mol%, and 100mol% vinylidene can be the upper limit. Accordingly, the uPAO may comprise vinylidene in an amount from about 10mol% to about 100mol%, from about 50mol% to about 100mol%, from about 80mol% to about 100mol%, or from about 95mol% to about 100mol% of the uPAO. [0066] The unsaturated olefin compound may have any suitable average molecular weight. The unsaturated olefin compound may have an average molecular weight selected from: greater than about 100; greater than about 200; greater than about 6,000; greater than about 16,000. It is useful when the unsaturated olefin compound has an average molecular weight of at least about 100 up to about 10,000. Particularly, the average molecular weight can be from about 100 to about 1000, and more preferably, from about 100 to about 500. The average molecular also can be, for example, greater than about 100 and less than about 1 ,000; greater than about 200 and less than about 1 ,000; greater than about 100 and less than about 500; and greater than about 200 and less than about 500.

[0067] The compositions of the present invention may include any suitable unsaturated polyalphaolefin (uPAO).

[0068] The unsaturated olefin compound can be an unsaturated polyalphaolefin prepared with a metallocene catalyst (mPAO). Different grades of unsaturated PAOs are available, depending on their nominal KV100, cSt (KV is kinematic viscosity).

[0069] An unsaturated poly alpha olefin molecule which is polymeric, typically oligomeric, produced from the polymerization reactions of alpha-olefin monomer molecules (generally Ce to about C20 olefins) in the presence of a catalyst system given by the general structure (F-1) may be used. where R ¹ , R ^2a , R ^2b , R ³ , each of R ⁴ and R ⁵ , R ⁶ , and R ⁷ , the same or different at each occurrence, independently represents a hydrogen or a substituted or unsubstituted hydrocarbyl (such as an alkyl) group, and n is a non-negative integer corresponding to the degree of polymerization. Where R ¹ , R ^2a and R ^2b are all hydrogen, (F-1) represents a vinyl PAO; where R ¹ is not hydrogen, and both R ^2a and R ^2b are hydrogen, (F-1) represents a vinylidene PAO; where R ¹ is hydrogen, and only one of R ^2a and R ^2b is hydrogen, (F-1) represents a disubstituted vinylene PAO; and where R ¹ is not hydrogen, and only one of R ^2a and R ^2b is hydrogen, then (F-1) represents a trisubstituted vinylene PAO. Where n=0, (F-1) represents an PAO dimer produced from the reaction of two monomer molecules after a single addition reaction between two C=C bonds.

[0070] When n=0, the unsaturated poly alpha olefin molecule has the structure: where R ¹ , R ^2a , R ^2b , R ³ , R ⁶ and R ⁷ are as defined above and where R ¹ +R ^2a +R ^2b +R ³ +R ⁶ +R ⁷ combined has an even number of saturated hydrocarbons ranging from 8 to about 36 carbons.

[0071] Suitable uPAOs include those supplied by ExxonMobil. Preferably, high vinylidene uPAOs prepared with selected metallocene catalysts as disclosed in US Patent Application Publication No. 2019/0248936 A1 (ExxonMobil) and US Patent Application Publication No. 2019/0359745 A1 (ExxonMobil), the entire contents of both of which are incorporated by reference. These materials have a residual olefin in the terminal position of the polymer backbone, with examples of unsaturated poly alpha olefin molecules having a residual olefin in the terminal position of the polymer backbone including the unsaturated poly alpha olefin molecules referred to in the following examples (i.e., F-1 -a, F-1 -b, F-1 -c and F-1 -d):

[0072] The unsaturated poly alpha olefin molecule may be an unsaturated metallocene derived a-olefin dimer, obtained from ExxonMobil, and referred to as F-1 -a herein.

[0073] The unsaturated poly alpha olefin molecule may be unsaturated metallocene derived a-olefin oligomers with approximate Kinematic Viscosity @ 100 °C of about 40 cSt, obtained from ExxonMobil, and referred to as F-1 -b herein. [0074] The unsaturated poly alpha olefin molecule may be ExxonMobil™ Intermediate u65 with approximate Kinematic Viscosity @ 100 °C of 65 cSt, supplied by ExxonMobil, and referred to herein as F-1 -c.

[0075] The unsaturated poly alpha olefin molecule may be ExxonMobil™ Intermediate u150 with approximate Kinematic Viscosity @ 100 °C of 150 cSt, supplied by ExxonMobil, and referred to herein as F-1 -d.

[0076] Preferably, the unsaturated poly alpha olefin molecule is F-1-c or F-1-d. More preferably, the unsaturated poly alpha olefin molecule is F-1 -a or F-1 -b.

[0077] The unsaturated olefin compound may be selected from monovinyl silicones, unsaturated monofunctional olefins and polyolefins, (meth)acrylates, alkenyl functional ethers, esters, carbonates and mixtures thereof. Particularly, the unsaturated olefin compound is selected from one or more mono-vinyl polydimethyl siloxanes (PDMS). The unsaturated olefin compound may be selected from an unsaturated a-olefin dimer, an alkyl 3,3-dimethyl-4-pentenoate, an alkyl-10-undeconoate, an alkyl methacrylate, an alkyl acrylate, an alkyl 3,3-dimethyl-4-pentenoate, styrene, 3-ethyl-3-oxetanylmethyl 3,3- dimethyl-4-pentanoate, ally ester of linear or branched iso-steric acid and mixtures thereof. More particularly, the unsaturated olefin compound is selected from an unsaturated a-olefin dimer, lauryl 3,3-dimethyl-4-pentenoate, butyl 10-undeconoate, dodecyl methacrylate, tridecyl acrylate, dodecyl 3,3-dimethyl-4-pentenoate, styrene, 3- ethyl-3-oxetanylmethyl 3,3-dimethyl-4-pentanoate, ally ester of linear or branched isosteric acid and mixtures thereof.

[0078] More than one unsaturated olefin compound can be used to prepare the silicone-hybrid resin. For example, a curable composition may include an unsaturated a-olefin oligomer and an unsaturated a-olefin dimer. For a two-part composition, an unsaturated olefin compound may be in each part. A one-part composition also may include more than one unsaturated olefin compound. For example, as in Example 1 , a curable one-part composition may include a mono-vinyl polydimethyl siloxane (PDMS) having an average molecular weight of greater than about 6,000 and a mono-vinyl siloxane (PDMS) having an average molecular weight greater than about 16,000, such as 16,666. [0079] The unsaturated olefin compound is desirably flowable at room temperature.

[0080] The unsaturated olefin compound is desirably made from about 6 to about 20 carbon atoms.

[0081] The unsaturated olefin compound may have a viscosity from about 10 cps to about 4000 cps. The unsaturated olefin compound may have a viscosity less than about 125 cps. The unsaturated olefin compound also may have a viscosity from about 125 cps to about 3500 cps. Desirably, the unsaturated olefin compound is a uPAO dimer having a viscosity of about 25 cps. Viscosities are measured with a Brookfield CAP 2000+ viscometer at room temperature.

[0082] The unsaturated olefin compound may be present in amounts of about 1 % to about 80 % by weight of the total resin composition. Preferably, the unsaturated olefin compound may be present in amounts of about 40% to about 80% by weight of the total resin composition. More preferably, the unsaturated compound may be present in amounts of about 60% to about 70% of the total resin composition.

[0083] The unsaturated olefin compound is the "comb" monomer used to form the side chain(s) of the comb-like network structure of the silicone-hybrid resin.

[0084] The compound comprising at least one silicone hydride functional group is used to form the backbone of the silicone-hybrid resin.

[0085] The compound comprising at least one silicon hydride functional group ("silicon hydride functional compound") which is useful for preparing the silicone-hybrid resin includes, for example, a hydrido-functional polydimethylsiloxane. It is useful when the silicon hydride functional compound comprises silicon hydride functional groups at terminal ends thereof. For example, it is useful when the silicon hydride functional compound comprises at least two silicon hydride functional groups. A particularly useful silicon hydride functional compound is a siloxane. For example, the silicon hydride functional compound may be a siloxane having a backbone comprising at least two silicon hydride functional groups attached to the backbone. It is useful when the silicon hydride functional compound is a siloxane having a backbone comprising at least two silicon hydride functional groups attached to the backbone at terminal ends thereof. The silicon hydride functional compound may be polydimethylsiloxane (PDMS). It is useful when PDMS with methylhydridosiloxane groups is the basis for the hybrid polymer. It is particularly useful when the silicon hydride functional compound is methylhydridosiloxane-dimethylsiloxane copolymer.

[0086] The silicon hydride functional compound may have an average molecular weight from at least about 100 up to at least about 20,000. For example, the silicone hydride functional compound may have an average molecular weight of greater than about 1000. It is useful when the silicon hydride functional compound has an average molecular weight of greater than about 3000. It is particularly useful when the average molecular weight of the silicone hydride functional compounds is from about 6000 to about 12,000.

[0087] The silicon hydride functional compound may have a viscosity of about 500 cps or less. Viscosities are measured at room temperature with a Brookfield viscometer.

[0088] The silicon hydride functional compound may be present in amounts of about 1 % to about 80% by weight of the total resin composition. Preferably, the silicon hydride functional compound may be present in amounts of about 40% to about 60% by weight of the total resin composition. More preferably, the silicon hydride functional compound may be present in amounts of about 30% to about 50% by weight of the total resin composition.

[0089] The curable compositions including the unsaturated olefin compound and the silicon hydride functional group include a crosslinker including vinyl and/or vinylidene and/or vinylene groups (hereinafter "the crosslinker component"). The curable compositions including the unsaturated olefin compound and the silicon hydride functional compound may include a crosslinker component including at least two vinyl or vinylidene or vinylene groups.

[0090] Many choices for the crosslinker are available. The crosslinker component may be selected from, for example, hexanediol dimethacrylate, 1 ,7-octadiene, trimethylolpropane triacrylate, triallyl cyanurate, triallyl isocyanarate, adipic acid diallyl ester, diallyl ether bisphenol A, 1 ,5-pentane diol-10-undecenoate (also known as PD 10- undecenoate), 2-butyl-2-ethyl-1 ,3-propanediol 3,3-dimethyl-4-pentenoate (also known as BEPD Pentenoate), average molecular weight <30,000 vinyl terminated PDMS, dimer diol 3,3-dimethyl-4-pentenoate, hydrogenated polybutadiene 3,3-dimethyl-4- pentenoate. A particularly useful crosslinker component is 1 ,6-hexanediol dimethacrylate (1 ,6,-HDDMA), which is commercially available from Miwon.

[0091] It will be understood that where a crosslinker component including at least two vinyl or vinylidene functional groups is disclosed for use in the compositions, adducts, systems, methods and reactions disclosed herein, a vinylene compound with one or multiple internal double bonds -CH=CH- may be used instead as the crosslinker component. Accordingly, a vinylene compound with one of more multiple internal bonds double bonds -CH=CH- may be used as the crosslinker component with the SiH compound instead of using the crosslinker component including at least two vinyl functional groups with the SiH compound. The molecular weight of the vinylene compound including one of more multiple internal double bonds -CH=CH- may have an average molecular weight of at least about 100 up to about 10,000. An example of a compound having multiple internal double bonds for use as a crosslinker component in the compositions, adducts, systems, methods and reactions disclosed herein (in lieu of the crosslinker component including at least two vinyl functional groups) is high oleic soybean oil (MW of about 880), which is a polyunsaturated triglyceride and also a renewable resource. Accordingly, instead of a crosslinker component including at least two vinyl functional groups, the crosslinker component may be a vinylene compound including one or multiple internal double bonds-CH=CH- which is a renewable resource, such as high oleic soybean oil (MW of about 880).

[0092] The crosslinker component may be present in amounts of about 1 % to about 20% by weight of the total composition. Preferably, the crosslinker component may be present in amounts of about 2% to about 10% by weight of the total composition. More preferably, the crosslinker component may be present in amounts of about 3% to about 7% by weight of the total composition.

[0093] The balance between the components can be adjusted to change the hardness of the composition. Styrene is particularly useful co-monomer for adjusting hardness and mechanical properties. The effectiveness of the thermal interface material to transfer heat is significantly impacted by the interface between the TIM and the heat source and a soft, conformable material can optimize the contact at the interface.

[0094] The ratio of the unsaturated olefin compound to the silicon hydride functional compound may be selected to optimize the hardness of the composition. Preferably, the ratio of unsaturated olefin compound to the silicon hydride functional compound ranges from about 0.5 : 1 to about 2 : 1 where the ratio is molar by functionality. More preferably, the ratio of the unsaturated olefin compound to the silicon hydride functional compound ranges from about 0.8 : 1 to about 1 .2 : 1 where the ratio is molar by functionality.

[0095] The vinyl:SiH reactive group ratio may be in the range of about 0.5:1 to 2:1. More particularly, the vinyl: SiH reactive group ratio may be in the range of about 0.8:1 to 1.2:1.

[0096] The Shore OO Hardness, measured at 24 hours at about 25 °C, of the silicone- hybrid resin may be: less than about 90; less than about 80; or from about 1 to about 90. The resin is a soft, conformable material that can optimize the contact at the interface, which it is placed onto.

[0097] A composition of the invention may include a filler, such as a thermally conductive filler. Thermally conductive fillers are known in the art and commercially available, see for example, US Patent No. 6,169,142 (col. 4, lines 7-33). The thermally conductive filler may be both thermally conductive and electrically conductive. Alternatively, thermally conductive filler may be thermally conductive and electrically insulating.

[0098] Specifically, useful thermally conductive fillers may comprise a metallic filler, an inorganic filler, a carbon-based filler, a thermally conductive polymer particle filler, or a combination thereof.

[0099] Metallic fillers include particles of metals and particles of metals having layers on the surfaces of the particles. These layers may be, for example, metal nitride layers or metal oxide layers on the surfaces of the particles. Suitable metallic fillers are exemplified by particles of metals selected from the group comprising aluminum, copper, gold, nickel, silver, and combinations thereof. Suitable metallic fillers are further exemplified by particles of the metals listed above having layers on their surfaces selected from the group comprising aluminum nitride, aluminum oxide, copper oxide, nickel oxide, silver oxide, and combinations thereof. For example, the metallic filler may comprise aluminum particles having aluminum oxide layers on their surfaces. The metallic filler may be an alumina blend, such as an alumina blend having spherical particles.

[0100] Inorganic fillers can include metal oxides such as aluminum oxide, beryllium oxide, magnesium oxide, and zinc oxide; nitrides such as aluminum nitride and boron nitride; carbides such as silicon carbide and tungsten carbide; and combinations thereof. Other examples include aluminum trihydrate, silicone dioxide, barium titanate, magnesium hydroxide.

[0101] Carbon-based fillers can include carbon fibers, diamond, graphite. Carbon nanostructured materials, such as one-dimensional carbon nanotubes (CNTs) and two- dimensional (2D) graphene and graphite nanoplatelets (GNPs) could also be used in the composition due to their high intrinsic thermal conductivity.

[0102] Examples of thermally conductive polymer fillers include oriented polyethylene fibers and nanocellulose. Other examples of polymers that could be used to make thermally conductive fillers include polythiophene, liquid crystalline polymers based on polyesters or epoxies, etc.

[0103] The shape of useful thermally conductive filler particles is not restricted; however, rounded or spherical particles may prevent viscosity increase to an undesirable level upon high loading of thermally conductive filler in the composition. Thermally conductive filler may be a single thermally conductive filler or a combination of two or more thermally conductive fillers that differ in at least one property such as particle shape, average particle size, particle size distribution, and type of filler. For example, a combination of inorganic fillers, such as a first aluminum oxide having a larger average particle size and a second aluminum oxide having a smaller average particle size can be included in the composition. Alternatively, a combination of an aluminum oxide having a larger average particle size with a zinc oxide having a smaller average particle size can be included in the composition. Combinations of metallic fillers, such as a first aluminum having a larger average particle size and a second aluminum having a smaller average particle size can alternatively be included in the composition. Further, combinations of metallic and inorganic fillers, such as a combination of aluminum and aluminum oxide fillers; a combination of aluminum and zinc oxide fillers; or a combination of aluminum, aluminum oxide, and zinc oxide fillers can alternatively be included in the compositions disclosed herein. The use of a first filler having a larger average particle size and a second filler having a smaller average particle size than the first filler may improve packing efficiency, may reduce viscosity, and may enhance heat transfer.

[0104] The thermally conductive filler may also include a filler treating agent. The filler treating agent may be any treating agent known in the art. The amount of filler treating agent may vary depending on various factors including the type and amounts of thermally conductive fillers. In a preferred embodiment, the filler treating agent will be included in the composition in an amount in the range of about 0.1 wt.% to about 5.0 wt.% of the filler.

[0105] The filler may be treated with filler treating agent in situ or pretreated before being combined with the resin to make the composite. The filler treating agent may comprise a silane such as an alkoxysilane, an alkoxy-functionalized oligosiloxane, a cyclic polyorganosiloxane, a hydroxyl-functionalized oligosiloxane such as a dimethyl siloxane or methyl phenyl siloxane, a stearate, or a fatty acid. Alkoxysilane filler treating agents are known to the art and are exemplified by hexyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetradecyltrimethoxysilane, phenyltrimethoxysilane, phenylethyltrimethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, and a combination thereof.

[0106] Alternatively, the filler treating agent can be any organosilicon compounds typically used to treat silica fillers. Examples of these organosilicon compounds include, but are not limited to, organochlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, and trimethyl monochiorosilane; organosiloxanes such as hydroxy-endblocked dimethylsiloxane oligomer, hexamethyldisiloxane, and tetramethyldivinyldisiloxane; organosilazanes such as hexamethyldisilazane and hexamethylcyclotrisilazane; and organoalkoxysilanes such as methyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3- methacryloxypropyltrimethoxysilane.

[0107] Alternatively, a polyorganosiloxane capable of hydrogen bonding is useful as a filler treating agent.

[0108] In certain embodiments, in addition to thermally conductive filler, the filler may also comprise a reinforcing filler, an extending filler, or a combination thereof.

[0109] When the compositions disclosed herein are in TIMs, electrically insulating, thermally conductive fillers are commonly included. Preferably, the thermally conductive filler material for use in the composition disclosed herein is selected from the group comprising aluminum oxide, boron nitride, aluminum nitride, magnesium oxide, zinc oxide, or a combination thereof. For commercial sources, CB-A205 and AI-43-Me are aluminum oxide fillers of differing particle sizes commercially available from Showa- Denko, DAW-45 is aluminum oxide filler commercially available from Denka, and AA-04, AA-2, and AA18 are aluminum oxide fillers commercially available from Sumitomo Chemical Company. Zinc oxides are available from Zochem LLC.

[0110] Other suitable fillers and/or additives may also be added to the compositions disclosed herein to achieve various composition properties. Examples of additional components that may optionally be added include pigments, plasticizers, process aids, flame retardants, extenders, electromagnetic interference (EMI) or microwave absorbers, electrically conductive fillers, magnetic particles, etc. A wide range of materials may be added to a TIM according to exemplary embodiments, such as carbonyl iron, iron silicide, iron particles, iron-chrome compounds, metallic silver, carbonyl iron powder, SENDUST (an alloy containing 85% iron, 9.5% silicon and 5.5% aluminum), permalloy (an alloy containing about 20% iron and 80% nickel), ferrites, magnetic alloys, magnetic powders, magnetic flakes, magnetic particles, nickel-based alloys and powders, chrome alloys, and any combinations thereof. Other embodiments may include one or more EMI absorbers formed from one or more of the above materials where the EMI absorbers comprise one or more of granules, spheroids, microspheres, ellipsoids, irregular spheroids, strands, flakes, powder, and/or a combination of any or all of these shapes. Some exemplary embodiments may include TIMs where the TIMs are configured (e.g., include or are loaded with EMI or microwave absorbers, electrically conductive fillers, and/or magnetic particles, etc.) to provide shielding.

[0111] In a useful embodiment, thermally conductive filler material is present in the first part of the composition in an amount in the range of about 30-95 wt.%, for example from about 85-95 wt.% based on the total weight of the first part. In another useful embodiment, the thermally conductive filler material is present in the second part in an amount in the range of about 30 wt.% to about 95 wt.%, for example amount from about 85 wt.% to about 95 wt.% based on the total weight of the second part. In yet another useful embodiment, the thermally conductive filler material is present both in the first and the second parts in an amount of about 30 wt.% to about 95 wt.%, and the total weight, based on both parts, of the thermally conductive filler material is present in an amount of about 30 wt.% to about 95 wt.%, preferably from about 85-95 wt.%.

[0112] A composition or system as described herein which includes one or more fillers is referred to as filled. A composition or system as described herein which does not include one or more fillers is referred to unfilled.

[0113] One or several catalysts can be included in the compositions disclosed herein to tune the curing speed depending on the application and process requirements. In the two-part composition disclosed herein, the unsaturated olefin compound and the silicon hydride functional compound are each dispensed and then mixed to be reacted. If the catalyzed reaction is too fast, the reactants may clog the dispensing mechanism. If the catalyzed reaction is too slow, the composite may flow out of the area where it is intended to be set after application and contaminate other surrounding components. Accordingly, the reaction speed is critical to obtain the desired properties of the composition. Suitable catalysts include hydrosilation catalysts. The most widely used hydrosilylation catalyst are based on platinum compounds including oxides. For example, a particularly useful catalyst is Karstedt catalyst, which is a platinum- divinyltetramethyldisiloxane complex, typically supplied as a 2-3% Pt solution in xylene (for example SIP6831 .2 from Gelest) or in divinyl polydimethylsiloxane (for example SIP6830.3 from Gelest). Another common platinum catalyst is H2PtCle (Speier's catalyst). Beyond platinum, metal complexes such as [RhCI(PPhs)3] (Wilkinson’s catalyst), RuCl2(CO)2(PPh3)2, [Cp*Ru(MeCN)s]PF6 (a metallocene compound, Cp*= pentamethylcyclopentadienyl), have also been used for hydrosi lation reactions. Even noble metal particles based on platinum (Pt), rhodium (Rh) and ruthenium (Ru) have been explored for this chemical transformation. More recently, a wide range of catalysts have been found useful, as described in a recent publication in Polymers, 2017, 9(10): 534 titled "Fifty Years of Hydrosilylation in Polymer Science: A Review of Current Trends of Low-Cost Transition-Metal and Metal-Free Catalysts, Non-Thermally Triggered Hydrosilylation Reactions, and Industrial Applications". These include low- cost transition metal catalysts such as iron, cobalt, and nickel complexes, metal-free catalysts. Additional developments are discussed in Nature Reviews Chemistry, volume 2, pages 15-34(2018) titled "Earth-abundant transition metal catalysts for alkene hydrosilylation and hydroboration", as well as in RSC Adv., 2015,5, 20603-20616 titled "Hydrosilylation reaction of olefins: recent advances and perspectives".

[0114] For one-part compositions, volatile inhibitors might be added to the catalyst system. Upon exposure to air, these inhibitors will evaporate to allow the reaction to proceed. Alternatively, a UV generated platinum catalyst might be used to trigger reaction.

[0115] The curable compositions may include wetting and dispersing additives. Suitable wetting and dispersing additives include, for example, BYK-9076, BYK-W 969, Disperbyk-108, Disperbyk-118, Disperbyk-168, Disperbyk-2008 and Disperbyk-2152, which are all supplied by BYK.

[0116] The curable compositions may include silicone free air release agents. Suitable free air release agents include, for example, BYK-1794, BYK-A 535, and BYK- A 500, which are all supplied by BYK. [0117] It is desirable to have some latency in the first hour of the reaction, and the catalyst may be chosen to dial-in this efficacy. This is particularly useful for two-part gap filler applications, to allow positioning of the parts, and fully cure within 48, and preferably within 24 hours. This allows time to rework the material to reposition the material without damaging expensive component substrates.

[0118] The composition may optionally further comprise up to about 80 wt.%, by weight of the composition of a liquid plasticizer in the first and/or second part. Suitable plasticizers include paraffinic oil, naphthenic oil, aromatic oil, long chain partial ether ester, alkyl monoesters, epoxidized oils, dialkyl diesters, aromatic diesters, alkyl ether monoester, polybutenes, phthalates, benzoates, adipic esters, acrylate and the like.

[0119] In one embodiment, the curable composition further comprises a moisture scavenger. Preferably the moisture scavenger is selected from the group comprising oxazolidine, vinyloxy silane, and combinations thereof. Vinyloxy silane is a particularly useful moisture scavenger.

[0120] The compositions disclosed herein may further optionally comprise up to about 3.0 wt.%, for example about 0.1 wt.% to about 2.5 wt.%, and preferably about 0.2 wt.% to about 2.0 wt.%, by weight of the resin composition in each part, of one or more of an antioxidant or stabilizers.

[0121] Useful stabilizers or antioxidants include, but are not limited to, high molecular weight hindered phenols and multifunctional phenols such as sulfur and phosphorus- containing phenols. Hindered phenols are well known to those skilled in the art and may be characterized as phenolic compounds which also contain sterically bulky radicals in close proximity to the phenolic hydroxyl group thereof. In particular, tertiary butyl groups generally are substituted onto the benzene ring in at least one of the ortho positions relative to the phenolic hydroxyl group. The presence of these sterically bulky substituted radicals in the vicinity of the hydroxyl group serves to retard its stretching frequency, and correspondingly, its reactivity; this hindrance thus provides the phenolic compound with its stabilizing properties. Representative hindered phenols include;

1 ,3,5-trimethyl-2,4,6-tris-(3,5-di-tert-butyl-4-hydroxybenzyl )-benzene; pentaerythrityl tetrakis-3(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate; n-octadecyl-3(3,5-ditert-butyl-4- hydroxyphenyl)-propionate; 4,4'-methylenebis(2,6-tert-butyl-phenol); 4,4'-thiobis(6-tert- buty l-o-cresol); 2,6-di-tertbutylphenol; 6-(4-hydroxyphenoxy)-2,4-bis(n-octyl-thio)-1 ,3,5 triazine; hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate; and sorbitol hexa[3-(3,5-ditert- butyl-4-hydroxy-phenyl)-propionate].

[0122] Useful antioxidants are commercially available from BASF Corporation and include lrganox®565, 1010, 1076 and 1726 which are hindered phenols. These are primary antioxidants that act as radical scavengers and may be used alone or in combination with other antioxidants, such as, phosphite antioxidants like IRGAFOS®168 available from BASF.

[0123] The inclusion of antioxidants and/or stabilizers in the compositions disclosed herein should not affect other properties of the composition.

[0124] One or more retarding agents can also be included in the composition to provide an induction period between the mixing of the two parts of the composite composition and the initiation of the cure. For useful hydrosilation retarding agents see, for example, US Patent No. 3,445,420, the entire contents of which are incorporated by reference herein, to use acetylenic compounds such as acetylenic alcohols with a boiling point of less than 250 °C, in particular, 2-methyl-3-butyn-2-ol and ethynyl- cyclohexanol, as hydrosilylation inhibitors in curable silicone compositions based on an organosiliceous polymer bearing substituents having olefinic unsaturation (in particular, vinylic unsaturation), on an organohydrosiloxane polymer and on a catalyst of the platinum or platinum compound type. The retarding agent also may be 8- hydroxyquinoline.

[0125] Further optional components can be added to the composition, such as for example, nucleating agents, elastomers, colorant, pigments, rheology modifiers, dyestuffs, mold release agents, adhesion promoters, flame retardants, a defoamer, a phase change material, rheology modifier processing aids such as thixotropic agents and internal lubricants, antistatic agents or a mixture thereof which are known to the person skilled in the art and can be selected from a great number of commercially available products as a function of the desired properties. The amounts of these additives incorporated in into the composition can vary depending on the purpose of including the additive.

[0126] The composition according to this invention may be used as a TIM to ensure consistent performance and long-term reliability of heat generating devices such as electronic devices. Specifically, these compositions can be used as a liquid gap filler material that can conform to intricate topographies, including multi-level surfaces. In particular, the compositions can be used as gap fillers which are liquid pastes. Due to the increased mobility prior to cure, the composition can fill small air voids, crevices, and holes, reducing overall thermal resistance to the heat generating device. Additionally, thermal interface gap pads can be prepared from this composition.

[0127] Manual or semiautomatic dispensing tools can be used to apply the composition directly to the target surface, resulting in effective use of material with minimal waste. Further maximization of material usage can be achieved with implementation of automated dispensing equipment, which allows for precise material placement and reduces the application time of the material. Accordingly, the viscosity of each part of the composition must be maintained such that the parts can be dispensed through the dispensing tools. Each of the first part and the second part has a viscosity of less than about 1500 Pa-s (cps) at room temperature, preferably a viscosity of less than about 500 Pa-s at room temperature.

[0128] For a filled composition (resin plus filler) to be dispensable, the viscosity, at 1/sec shear rate, is less than about 1500 Pa-s, preferably less than about 1000 Pa-s, and more preferably less than about 500 Pa-s. The viscosity may be measured by ASTM D2196 using a parallel plate rheometer, particularly the test is conducted on a TA Instruments HR-3 Discovery rheometer with 25 mm parallel plates. For example, a viscosity of from about 300 to about 500 Pa-s provides suitable stability. The shear rate is ramped from 0.3/second to 5/sec and viscosity value is recorded at 1/sec.

[0129] Typically, dispensing the material from a cartridge can take up to several hours. It is desirable to have a speed of at least 20 g/min for initial dispensing, since this ensures high throughput when the material is applied to an actual device. In addition, 30 to 60 min latency ensures that the mixing area does not get clogged during a temporary production pause. For example, sometimes the production line might be stopped, such as for inspection or a break, so it is desirable that the operation can resume without changing the static mixer.

[0130] A high dispensing rate is an advantage of the compositions and systems of the invention including a PAO. In particular, a high dispensing/extrusion rate out of a typical EFD syringe is an advantage of the compositions and systems including a PAO. For example, the dispensing rate out of, for example, a typical EFD syringe, for a single component (either Part A or Part B in a two component system) composition is greater than 30 mL/minute, preferably greater than 60 mL/minute and more preferably greater than 100 cc/minute. Such a test is conducted with material filled in a 30mL Nordson EFD syringe with a 0.1” orifice which is then dispensed at 75-90 psi for a given time (a few seconds to one minute).

[0131] Besides adhering to the molar ratios of the vinyl and silicon hydride functionalities in the mixture, it is desirable to dispense the same or substantially the same volume of both parts, A and B, to combine them in the mixing area. Generally, both parts have similar densities, but the weights can be adjusted based on the densities of each part to provide the same volume. Other volume mixing ratios may also be used, such as 1 :2, 1 :4, 1 :10.

[0132] The first part and second part of the composition can be mixed to form a composition that can be cured at room temperature. The mixed composition has a pot life of longer than about 10 minutes, and preferably longer than about 20 min. It is desirable to have some latency in the first 30-60 minutes after mixing to allow positioning of the parts, and full cure within 24 hours. Longer curing times than 24 hours and slightly elevated curing temperatures above room temperature might also be useful. Curing of the compositions described herein generally occurs at room temperature but can be elevated up to 150 °C.

[0133] Upon standing, Part A and Part B materials in the static mixer begin to react, resulting in higher viscosity, and could even crosslink and clog the static mixer. If the dispensing rate reaches zero, then this indicates the materials have crosslinked and clogged the mixer. If clogging happens on a production line, the static mixer will need to be replaced or cleaned. Therefore, it is desirable to maintain some, if not all of the initial dispensability. After the initial dispensing rate of t=0, the dispensing rate at 30 - 60 minutes should be greater than zero, preferably greater than 70% of the dispensing rate of t=0 at 0.5 to 0.65 MPa and at room temperatures if 22-25 °C. For those skilled in the art, dispensing rate at 30-60 minutes can be adjusted by changing resin stoichiometry, using less catalyst, or moving catalyst from one part to another to minimize pre-reaction.

[0134] The composition, after room temperature cure, has a glass transition temperature (Tg) of less than about -20 °C, preferably less than about -30 °C. This is to prevent significant hardening during low temperature use. Further, the cured composition is thermally stable from about -40 °C to about 125 °C.

[0135] The Shore OO Hardness, measured at 24 hours at room temperature, i.e., about 22-25 °C, of an unfilled composition (resin without filler) may be from 0 to about 90, from about 0 to about 30 or from about 0 to about 20. The Shore OO hardness, measured at 24 hours at room temperature, i.e., about 22-25 °C, for a filled composition (resin plus filler) is less than about 90 or less than about 80. The Shore OO hardness test is at room temperature using a Shore OO Scale Ergo Durometer 411 according to ASTM D2240 by PTC Instruments (Los Angeles, CA) or a Type 00, Model 1600 durometer from Paul N. Garnder Company, Inc. (Pompano Beach, Florida). The resin is a soft, conformable material that can optimize the contact at the interface, which it is placed onto.

[0136] A stable modulus at elevated temperatures indicate the resin as thermally stable, and the resin can maintain the shape as a TIM in use. Also, the gradual drop of the Tg, instead of sharp decline in G’, denotes heat stability of the cured resin. These characteristics of the resin ensure good dampening performance of the resin to minimize mechanical shock to its attached substrates. In one embodiment, the resin may be formed as a component in a device, e.g., an electronic device such as a battery, and thus, Shore OO Hardness less than about 90 is desirable since this allows for good damping performance to absorb shocks and minimizes damage in the material, rather than transferring that shock onto expensive battery components. In a preferred embodiment, Shore OO Hardness change of less than 50, usually less than 20 is desirable under aggressive aging conditions, e.g., 100 °C/2 hours. Many batteries operate under 80 °C. For a room temperature TIM that gets exposed to the upper temperature limit frequently, it is unwanted for the material to further cure and harden. Accordingly, testing is conducted at elevated temperature such as 100 °C to see if there are residual curing reactions.

[0137] In some exemplary embodiments, a TIM may include an adhesive layer. The adhesive layer may be a thermally conductive adhesive to preserve the overall thermal conductivity. The adhesive layer may be used to affix the TIM to an electronic component, heat sink, EMI shield, etc. The adhesive layer may be formulated using a pressure-sensitive, thermally conducting adhesive. The pressure-sensitive adhesive (PSA) may be generally based on compounds including acrylic, silicone, rubber, and combinations thereof. The thermal conductivity is enhanced, for example, by the inclusion of ceramic powder. Many ceramic powders have higher thermal conductivity than the adhesives.

[0138] In some exemplary embodiments, TIMs may be attached or affixed (e.g., adhesively bonded, etc.) to one or more portions of an EMI shield, such as to a single piece EMI shield and/or to a cover, lid, frame, or other portion of a multi-piece shield, to a discrete EMI shielding wall, etc. Alternative affixing methods can also be used such as, for example, mechanical fasteners. In some embodiments, a TIM may be attached to a removable lid or cover of a multi-piece EMI shield. A TIM may be placed, for example, on the inner surface of the cover or lid such that the TIM will be compressively sandwiched between the EMI shield and an electronic component over which the EMI shield is placed. Alternatively, a TIM may be placed, for example, on the outer surface of the cover or lid such that the EMI shield is compressively sandwiched between a TIM material and a heat sink. A TIM may be placed on an entire surface of the cover or lid or on less than an entire surface. A TIM may be applied at virtually any location at which it would be desirable to have an EMI absorber.

[0139] Further contemplated herein is a device comprising a heat-source, a heat sink, and the compositions disclosed herein disposed therebetween. In a preferred embodiment, the device does not leave an air gap between the heat source and the heat sink.

[0140] Also provided is a curable composition of the present invention made with no PAG or comb polymer.

EXAMPLES

[0141] Example 1 : Comb Network using Pendent Mono-vinyl Silicone

[0142] In this example, mono-vinyl polydimethylsiloxane (PDMS) was grated to a linear copolymer of methylhydridosiloxane-dimethylsiloxane, thus creating a comb structure, as shown in FIG. 3. Unfilled and filled samples were prepared using a FlackTek Speed Mixer. Hardness of cured samples were measured after 24h at room temperature using a Type 00, Model 1600 durometer from Paul N. Garnder Company, Inc. (Pompano Beach, Florida). Shore hardness of 0 indicates a gelled network, but not measurable with the testing instrument. Both inventive compositions #1 and #2 resulted in Shore OO <90 at 90 wt% alumina loading. All resin materials were obtained from Gelest Inc, Morrisville, PA. Details for Inventive Compositions #1 and #2 are listed in Table 1.

Table 1

Inventive Compositions #1 - #2

Average Molecular Weight

** EW is equivalent weight based on reactive functionalities

¹ Compound including at least one silicon hydride functional group

² Compound including unsaturated olefin having vinyl functionality located at a terminal end

³ Hydrosilation catalyst

⁴ Thermally conductive filler

[0143] It is known for those skilled in the art, that a divinyl compound (such as vinyl terminated polydimethylsiloxane) might be added to adjust crosslinking density and hardness. In the above case, however, it was determined that this component is not needed. Accordingly, no vinyl crosslinker was added directly to Inventive Compositions #1 and 2. In this example, the catalyst has a vinyl crosslinker in it.

[0144] A bleeding test was then conducted. A cured sample sheet #1 (filled) of 2540 microns was covered with porous fabric at top and bottom, then placed between two metal blocks with heat gradient of 75 °C under 40% compression. Sample sheet was weighed before and after testing. After 236h, <0.4% weight loss was observed, indicating minimal silicone bleeding.

[0145] Example 2: Comb Network using Pendent Non-silicone Aliphatic Mono-vinyl Compounds

[0146] In this example, several non-silicone aliphatic mono-vinyl compounds were tested to replace mono-vinyl PDMS as the comb. Hexanediol dimethacrylate (HDDMA) was added as a crosslinker. Unsaturated alpha-olefin dimer was obtained from ExxonMobil. Lauryl 3,3-dimethyl-4-pentenoate was synthesized in accordance with Example 7. Butyl 10-undecenoate was obtained from Sigma Aldrich. Dodecyl methacrylate was obtained from TCI Chemicals. Tridecyl acrylate and hexanediol dimethacrylate were obtained from Miwon as Miramer M124, and M201 respectively. Crosslinker 100 was obtained from Evonik. SIP6831.2 was obtained from Gelest. All cured to Shore 00 hardness < 90, mostly at room temperature for 24-48h, or with mild heating. Details for Inventive Compositions #3 to #7 are shown in Table 2.

Table 2

Inventive Compositions #3 - #7

* EW is equivalent weight based on reactive functionalities

“ after r.t./7d and additional 80 °C/1 h (r.t. is room temperature; h is hour)

***r.t. is room temperature; h is hours

¹ F-1 -a ² Compound including unsaturated olefin having vinyl functionality at a terminal end

³ Compound including unsaturated olefin having vinyl functionality at a terminal end

⁴ Compound including unsaturated olefin having vinylidene functionality at a terminal end

⁵ Compound including unsaturated olefin having vinyl functionality at a terminal end

⁶ Compound including at least one silicon hydride functional group

⁷ Crosslinker including at least two vinylidene functional groups

⁸ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane)

[0147] As all of the tested non-silicone aliphatic mono-vinyl compounds cured to Shore 00 hardness of <90, all of those compounds can be used as the unsaturated olefin compound in the inventive compositions.

[0148] Example 3: Use of Styrene to Adjust Hardness and Mechanical Properties

[0149] An aromatic mono-vinyl compound, styrene, was also tested at different levels. All samples showed Shore 00 hardness <90. This experiment demonstrated the usefulness of styrene as a co-monomer to tune hardness and mechanical properties. Details for Inventive Compositions #8a, #8b and #8c are shown in Table 3.

Table 3

Inventive Compositions #8a - #8c

* Average molecular weight

** EW is equivalent weight based on reactive functionalities.

***r.t. is room temperature; h is hours

¹ F-1-a

² Compound including at least one silicon hydride functional group

³ Co-monomer

⁴ Crosslinker including at least two vinylidene functional groups

⁵ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane)

[0150] As shown by the results in Table 3, the Shore 00 hardness of the inventive compositions can be increased by increasing the mol% styrene in the inventive compositions.

[0151] Example 4: Two-part filled formulation based on unsaturated a-olefin dimer

[0152] A two-part filled formulation was created based on unsaturated a-olefin dimer. The details for two-part Inventive Composition #9 are shown in Table 4.

Table 4

Inventive Composition #9

‘Average molecular weight

“ EW is equivalent weight based on reactive functionalities

¹ F-1-a

² Compound including at least one silicon hydride functional group (Crosslinker 100 is a tradename. Crosslinker 100 is not the actual crosslinker in this example. It is a hydrido functional PDMS.)

³ Crosslinker including at least two vinylidene functional groups (actual crosslinker)

⁴ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane)

⁵ Thermally conductive filler

[0153] As is apparent from Table 4, Part A included a crosslinker including at least two vinyl functional groups (Hexanediol dimethacrylate) and a hydrosilation catalyst (SIP6831 .2). Part B included a compound including at least one silicon hydride functional group (Crosslinker 100). The crosslinker including at least two vinyl functional groups (Hexanediol dimethacrylate) and the hydrosilation catalyst (SIP6831 .2) were kept separate from the at least one silicon hydride functional group (Crosslinker 100) in different parts so that they did not prematurely react. Thus, by using a two-part formulation, it is possible to avoid a premature reaction.

[0154] Parts A and B were mixed. At 1 :1 weight ratio, a Shore OO hardness of 70 was obtained after 24h at room temperature. At 1 :1 volume ratio, a Shore OO hardness of 84 was obtained after 24h at room temperature. This later sample was found to have thermal conductivity of 3.6 W/m*K. For those skilled in the art, adjustment of the hexanediol dimethacrylate level could result in different hardness.

[0155] The reaction scheme of Inventive Composition #9 is represented in FIG. 4. [0156] Example 5: Crosslinked Comb Network Using Other Divinyl Compounds as Crosslinking Compounds

[0157] In this example, 1 ,7-octadiene was used as a divinyl compound at different levels. Unsaturated a-olefin dimer, F-1 -a, was reduced accordingly to maintain 1 :1 ratio of the vinyl group and the SiH group in the composition. As expected, hardness of the composition increased with more 1 ,7-octadiene. Details for Inventive Compositions #10a - #10d are shown in Table 5.

Table 5 Inventive Compositions #10a - #10d

Average molecular weight

EW is equivalent weight based on reactive functionalities

***r.t. is room temperature; h is hours

¹ F-1-a

² Compound including at least one silicon hydride functional group

³ Crosslinker including two vinyl functional groups

⁴ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane) [0158] In addition to 1 ,7-octadiene, several other crosslinkers were tested including acrylates, allyl compounds, undecenoates, pentenoates, vinyl terminated PDMS. Details for Inventive Compositions #11 - #18 are shown in Table 6.

Table 6 Inventive Compositions #11 - #18

‘Average molecular weight

** EW is equivalent weight based on reactive functionalities ***r.t. is room temperature; hr is hours

¹ F-1-a

² Compound including at least one silicon hydride functional group-a

³ Crosslinker

⁴ Crosslinker

⁵ Crosslinker

⁶ Crosslinker

⁷ Crosslinker

⁸ Crosslinker (PD 10-undecenoate: 1 ,5-pentanediol 10-undecenoate)

⁹ Crosslinker (BEPD Pentenoate: 2-butyl-2-ethyl-1 ,3-propanediol 3,3-dimethyl-4- pentenoate)

¹⁰ Crosslinker (Polymer VS 50: vinyl-terminated polydimethylsiloxane (PDMS))

¹¹ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane)

[0159] As is apparent from the Shore hardness measurements for Inventive Composition #16 in Table 6, PD 10-undecenoate: 1 ,5-pentanediol 10-undecenoate is a particularly useful crosslinker. As is apparent from the Shore hardness measurement at r.t/48hr + 1 hr@80 °C for Inventive Composition #17 in Table 6, BEPD Pentenoate is also a particularly useful crosslinker. All of the compositions resulted in crosslinked network Shore 00 hardness. Compositions that gave Shore 00 hardness of 0 within 24 hours at room temperature are especially useful. However, other compositions that can be cured at slightly longer times or mild temperatures are also useful. [0160] Example 6: Comb Network using Unsaturated Poly alpha-olefin Oligomer

[0161] F-1 -b was blended with alkyl or phenyl functional hydridosilicones and 1 ,7- octadiene was used as a crosslinker. Details for Inventive Compositions #19 and #20 are shown in Table 7.

Table 7 Inventive Compositions #19 - #20

* MW is average molecular weight

** EW is equivalent weight based on reactive functionalities

***r.t. is room temperature; h is hours

¹ F-1-b

² F-1 -a

³ Compound including at least one silicon hydride functional group

⁴ Compound including at least one silicon hydride functional group (HAM-301 : 25- 30% methylhydrosiloxane octylmethylsiloxane copolymer, 30-80 cST, supplied by Gelest) ⁵ Compound including at least one silicon hydride functional group (HPM-502: 45- 50% methylhydrosiloxane phenylmethylsiloxane copolymer, 75-110 cST, supplied by Gelest)

⁶ Crosslinker

7 Hydrosilation catalyst (platinum divinyltetramethyldisiloxane)

[0162] The results show how it is possible to formulate with higher MW uPAO and still obtain low hardness.

[0163] Example 7: Synthesis of Diesters of Undecylenic Acid

[0164] 10-Undecenoate Diester Based on Hydrogenated Polybutadiene Backbone (Vinyl Crosslinkers)

[0165] This example describes the synthesis of exemplary useful vinyl crosslinkers.

[0166] Into a two-neck 500 mL flask was added 123.5g (0.1 mol OH) Krasol HLBH-P 2000 (hydrogenated, hydroxyl-term inated polyolefin from Cray Valley), 18.4g (0.1 mol) undecylenic acid, 1.4g PTSA*H2O (p-Toluenesulfonic acid monohydrate from Millipore Sigma) (~ 1 wt%), and 200 mL toluene. The reaction was heated in an oil bath to 140- 160 °C, keeping a constant reflux. Most of the water was collected within the first hour. The reaction was continued for another 3h. A slightly brownish-red solution was obtained. NMR indicated complete reaction at this point.

[0167] The reaction was allowed to cool down, and 20g Reillex 425 (crosslinked poly-r-vinylpyridine macroporous weak polymer from Vertellus™ was added and stirred for 30min to scavenge soluble acid. The solution was passed through a column of 25g basic alumina, followed by rotary evaporator to remove toluene, giving 135.5g product. The yield was ~ 95%. This compound may be used as a crosslinker.

[0168] 10-Undecenoate Diester Based on Dimer Diol Backbone

[0169] Synthesis was conducted similarly using Pripol 2033-LQ (Dimer Diol) from Croda, using 108g (0.2 mol) Pripol 2033-LQ, 74g (0.4 mol) undecylenic acid, 2.0g PTSA*H2O (~ 1.1 wt%), and 200 mL toluene, resulting in 149g liquid. The yield was 86%. Pripol 2033-LQ has the following idealized structure:

[0170] The resulting resin has the following idealized structure:

[0171] ¹ H NMR (CDCI3, 400 MHz):

[0172] 5.88-5.71 (2H), 5.03-4.86 (4H), 4.11 -3.98 (4H), 2.35-2.21 (4H), 2.10-1 .96

(4H), 1.74-0.6 (90H)

[0173] This compound may be used as a crosslinker.

[0174] 10-Undecenoate Diester Based on 1,5-Pentane Diol Backbone

[0175] Synthesis was conducted similarly, using 20.8g (0.2 mol) 1 ,5-pentane diol, 73.6g (0.4 mol) undecylenic acid, 0.5g PTSA*H2O (p-Toluenesulfonic acid monohydrate from Millipore Sigma), 300 mL toluene. The reaction resulted in 78.0g liquid. The yield was 90% and purity was 99.3% based on GC analysis.

[0176] ¹ H NMR (CDCh, 400 MHz): 5.87-5.70 (2H), 5.03-4.85 (4H), 4.12-3.98 (4H), 2.33-2.20 (4H), 2.08-1.94 (4H), 1.73-1.50 (8H), 1.49-1.14 (22H)

[0177] This compound may be used as a crosslinker.

[0178] 10-Undecenoate Diester with a Pendant Group

[0179] Synthesis is conducted similarly using trimethylolpropane, undecylenic acid, isostearic acid (Nissan Chemicals) at 1 :2:1 molar ratio, resulting in the following structure as the main component

[0180] This compound may be used as a crosslinker.

[0181] Example 8: Synthesis of 3,3-dimethyl-4-pentenoate esters

[0182] Synthesis of a Difunctional 3,3-dimethyl-4-pentenoate based on 2-butyl- 2-ethyl-1,3-propanediol backbone

[0183] Into a two-neck flask fitted with a distillation head, receiving flask and nitrogen inlet was added 16.0g (0.1 mol) 2-butyl-2-ethyl-1 ,3-propanediol (Aldrich) and 31 ,0g (0.218 mol) methyl 3,3-dimethyl-4-pentenoate (TCI). Next, 0.1g potassium methoxide dissolved in 2.5 mL anhydrous methanol was added to the mixture with stirring. The reaction was heated to 110 °C for 1 ,5h with slow nitrogen purge until methanol formation stopped. The distillation head and nitrogen inlet were removed and the reaction flask was further heated at 90-110 °C under slightly reduced pressure for 3h. Distillation at 90 °C/100 micron gave ~12g product of 92% purity. Upon further distillation, a 97% purity product was obtained.

[0184] 1 H NMR (CDCI3, 400 MHz): 5.93-5.82 (2H), 5.00-4.90 (4H), 3.87 (4H), 2.30

(4H), 1.38-0.78 (26H). The resulting difunctional 3,3-dimethyl-4-pentenoate can be used as a crosslinker.

[0185] Synthesis of Dodecyl 3,3-dimethyl-4-pentenoate

[0186] The reaction was conducted as shown below:

[0187] Reaction was conducted similarly using 40g (0.22 mol) dodecanol (Aldrich), 100.0g (0.70 mol) methyl 3,3-dimethyl-4-pentenoate (TCI), and 1 ML potassium methoxide dissolved in methanol (25 wt%). Resulting in 62g product in 95% yield and purity of 98.7%.

[0188] ¹ H NMR (CDCh, 400 MHz): 5.96-5.83 (1 H), 5.02-4.89 (2H), 4.08-3.97 (2H), 2.33-2.25 (2H), 1 65-1.53 (2H), 1.42-1.18 (18H), 1.17-1.07 (6H), 0.94-0.80 (3H). The resulting Dodecyl 3,3-dimethyl-4-pentenoate may be used as a PAO replacement.

[0189] Synthesis of 3-ethyl-3-oxetanylmethyl 3,3-dimethyl-4-pentenoate

[0190] The reaction was conducted as shown below: excess

[0191] Kugelrohl distillation at 50-65 °C/100 micron gave a clear liquid with yield of 62%.

[0192] ¹ H NMR (CDCh, 400 MHz): 5.91-5.84 (1 H), 4.98-4.92 (2H), 4.44-4.36 (4H), 4.17 (2H), 2.33 (2H), 1.77-1.71 (2H), 1.13 (6H), 0.90-0.87 (3H). The resulting 3-ethyl-3- oxetanylmethyl 3,3-dimethyl-4-pentenoate also may be used as PAO replacement.

[0193] Synthesis of Multifunctional 3,3-dimethyl-4-pentenoate

[0194] Similarly, tri- and multifunctional 3,3-dimethyl-4-pentenoate resins are made:

[0195] The tri- and multifunctional 3,3-dimethyl-4-pentenoate resins may be used as a crosslinker.

[0196] Example 9: Synthesis of Allyl Ester of Iso-stearic Acid N

[0197] Into a two-neck 500 mL flask was added 56.8g (0.2 mol) iso-stearic acid N (Nissan Chemicals), 25g (0.43 mol) allyl alcohol, 0.3g PTSA’F , and 350 mL toluene. The reaction was heated in an oil bath to 120-130 °C. The azeotrope of allyl alcohol/toluene/water was collected in batched of ~30 mL, dried over 30g anhydrous MgSO4 powder, filtered, and returned to the reaction. This process was repeated three times. The solution was washed with 200 mL DI water three times, passed through basic alumina column. After solvent removal, 43.6g (67% yield) product was obtained. GC-Mass indicated a broad peak of various isomers of the following structure: o

[0198] Example 10: Curable Optical Compositions using BEPD Pentenoate and Hydridosilicones

[0199] In this example, HPM-502 (Gelest) is 45-50% methylhydrosiloxanephenylmethylsiloxane copolymer, hydride terminated. HMS-992 (Gelest) is polymethylhydrosiloxane, trimethylsilyl terminated. SIP6830.3 (Gelest) is platinum- divinyltetramethyldisiloxane complex with 3-3.5% platinum concentration in vinyl terminated polydimethylsiloxane. BEPD Pentenoate may be prepared as set forth in Example 8. The details for Inventive Compositions #21 and #22 are set forth in Table 8. For each resin, the equivalent weight (EW) of the functional group is listed in Table 8

Table 8 Inventive Compositions #21 - #22

* Equivalent Weight based upon reactive functionalities

¹ Crosslinker

² Hydridosilicone (Compound including at least one silicone hydride functional group)

³ Hydridosilicone (Compound including at least one silicone hydride functional group)

⁴ Hydrosilation catalyst (platinum divinyltetramethyldisiloxane) [0200] Both formulations were cured to give clear, colorless samples. This example illustrates how a curable composition of the present invention may be made using a multifunctional pentanoate resin.

[0201] Example 11 : Combined Light-heat Aging

[0202] Cured disks having an area around 1 cm ² and thickness of 1 mm were placed on a hotplate with surface temperature of 170 °C. One cured disk was prepared using Inventive Composition #22, as prepared in Example 10. One cured disk was prepared using Comparative Formulation 1 (epoxy) and another cured disk was prepared using Comparative Formulation 2 (normal Rl silicone). Each disk was irradiated with a high power blue light LED through focusing optics, resulting in a ~50W/cm ² light density spot on the sample. Test was conducted for 12 days. The results are shown in Table 9.

Table 9

[0203] Moisture permeation was measured with MOCON PERMATRAN-W 3/33. As demonstrated by this example, silicone hybrid formulation based on BEPD pentanoate and HMS-992 demonstrated significantly better combined heat/photo aging performance compared to commercial epoxy, as well as much better barrier performance compared to commercial normal Rl silicone.

[0204] Example 12: LED device testing

[0205] Into a 20 mL scintillation vial was added 0.0424g 2% toluene solution of SIP6832.2 (Gelest), 2.2646g BEPD pentenoate, followed by 1.9384g 1 ,4- bis(dimethylsilyl)benzene (SIB1086.0, Gelest). The reaction was mixed at 90 °C oil bath for 2h. Next, 0.6072g 1 , 3, 5, 7 tetravinyl- 1 , 3, 5, 7 tetramethyl cyclotetrasiloxane (SIT 7900, Gelest) was mixed. This sample (formulation #23) was degassed and cured for 2hr at 100 °C, 1 hr at 120 °C and 4hr at 150 °C in LED cups. Live device aging test was conducted with 350mA current. As shown in FIG. 5, LED devices encapsulated with this formulation showed no drop in relative light output for over 5000hrs. Moisture permeation of this sample was found to be 37 g*mil/100in ² *day at 50 °C, 100% humidity.

[0206] Example 13: Comparative Example

[0207] A two-part commercial formulation having components as set forth in Table 10 was used to conduct a bleeding test.

Table 10

[0208] In the formulation set forth in Table 10, the ratio of vinykSiH is 2.46:1 , indicating that if one end group from the divinyl silicone is reacted, some unreacted divinyl silicones will still remain in the final cured sample.

[0209] A bleeding test was conducted under the same condition as Example 1 under heat gradient of 75 °C and 40% compression. This resulted in 1 .2% weight loss. Weight loss over 0.5% is considered high. Note the filler content in this formulation is slightly higher than our Example 1 , filled inventive composition #1, yet still resulted in higher resin bleed. The excess divinyl silicone was used to reduce Shore OO hardness to <90. This is in contrast to the Inventive compositions which allow for low hardness without relying on excess divinyl silicone for plasticizing effect.

[0210] Example 14: Resin Bleed After Curing Test

[0211] A uPAO-silicone hybrid material formed from a curable composition of the invention, i.e., Inventive Composition #9 from Example 4, a 3.5W/m*K commercial silicone thermal interface material (not containing a uPAO-silicone Hybrid material) and another commercial silicone thermal interface material (not containing a uPAO-silicone hybrid material) were cured in 40 mil press mold between release films. A 1 ’ disk was cut out and sandwiched between filter papers. The assembly was cut out and sandwiched between filter papers. The assembly was pressed under 2 Kg weight for 2 minutes before being placed in a 100 °C oven for 60 hours. As shown in FIG. 6A, no resin ring was observed the for the uPAO-silicone hybrid, which indicates that the resin did not bleed after curing. In contrast, a resin ring indicative of bleeding was observed for each of the commercial silicone thermal interface materials not containing a uPAO- silicone hybrid material, as shown in FIGS. 6B and 6C, respectively. The resin ring in each of FIGS. 6B and 6C is indicated by an arrow.

[0212] Example 15: Headspace GC Comparison Under High Heat

[0213] A uPAO-silicone hybrid material prepared from Inventive Composition #9, as set forth in Example 4, and a 3.5W/m*K commercial thermal silicone thermal interface material was heated at 135 °C for 2 hours and four samples of outgassing were collected in headspace vials for each of the materials, as schematically shown in FIG. 7.

The results are shown in Table 11 . D3-D6 are 3-6 -SiO- repeating unit volatile cyclics.

Table 11

[0214] As is apparent from Table 11 , the inventive uPAO-silicone hybrid material exhibited much less out outgassing than the commercial material not containing the inventive uPAO-silicone hybrid.

[0215] Example 16: Room Temperature Extraction of Cured Samples (ASTM Test)

[0216] A room temperature extraction of cured samples (ASTM) test was conducted in accordance with ASTM Designation: F 2466 - 05, which is standard practice for determining silicone volatiles in silicone rubber for transportation applications. Silicone volatiles (PPM) and aliphatic volatiles (PPM) of a uPAO-silicone hybrid formed from Inventive Composition #9, as set forth in Example 4, and of a 3.5W/m*K commercial thermal silicone thermal interface material were measured using room temperature extraction in accordance with the ASTM Test. The results are set forth in Table 12.

Table 12

*not applicable [0217] The aliphatic volatiles in the inventive uPAO-silicone hybrid are residual uPAO dimer. As is apparent from the results in Table 12, the inventive uPAO-silicone hybrid does not contain detectable silicones after curing. The commercial material, in contrast, contained a significant amount of detectable silicone volatiles after curing.

[0218] Example 17: Rheology Profile Comparison

[0219] A rheology profile comparison was done for the commercial material in Example 16, Table 12 above (a pure silicone system) and an inventive uPAO-silicone hybrid prepared from the Inventive Composition # 9, as set forth in Example 4. The results are shown in FIG. 8. As is apparent from FIG. 8, in comparison to the commercial material, a lower and smooth Tg transition was seen for the hybrid system, which potentially allows application below - 50 °C. By reducing the amount of the crosslinkers, it is possible for those skilled in the art to further lower the plateau modulus, and thus reduce hardness of the hybrid system if needed.

[0220] Example 18: Curable Composition using Vinylene Resins

[0221] This example demonstrates the possibility of using vinylene resins to make hydrosilation curable networks. A mixture of 2.7g (9.1 mmol) methyl oleate (methyl cis- 9-octadecenoate) was mixed with 0.3g (~1 mmol vinylene groups) high oleic soybean oil (CHS Processing and Food Ingredients, MN), 1.28g Crosslinker 100 (10 mmol), and 0.03g SIP6831 .2 catalyst. Methyl oleate was used as a monofunctional comb material while high oleic soybean oil was used as a multifunctional crosslinker component. High oleic soybean oil is a glycerol ester (triglyceride) of various fatty acids, of which about 75% are oleic acids having one vinylene group on the chain, about 8.7% are linoleic acids having two vinylene groups on the chain, 2.3% are linolenic acids having three vinylene groups on the chain, and the rest are saturated fatty acids having 1 to 24 hydrocarbons. On average, one high oleic soybean oil molecule has close to three double bonds per molecule.

[0222] After 24h at room temperature, this composition cured to a gel with Shore OO hardness about 50, which increased to about 68 after 48h at room temperature. This design approach is particularly useful when raw materials derived from naturally abundant sources are desired.