Use of calcium carbonate particles as tackifier in a tacky or adhesive polymer formulation, and adhesive polymer compositions comprising such calcium carbonate particles Technical field of the invention

The present invention relates to adhesive polymer formulations.

Background of the invention

When formulating an adhesive polymer formulation, the chemist needs to select the right type of tackifier resin to secure that it has the proper solubility with the core polymer component in the formulation. Some types of tackifier resins work well with non-polar polymers while others work best with polar polymers, and vice versa, and again other types are suitable for medium polar polymers. Furthermore, tackifier resin may have a negative effect on the adhesive polymer formulations’ properties at elevated temperatures, thereby limiting the maximum amount that may be added. Additionally, some types of tackifier resins have poor solubility, thereby also limiting the maximum amount that may be added.

Thus, there exists a need for an alternative type of tackifier that may solve or alleviate the above-mentioned problems.

Summary of the invention

It has surprisingly been found out that calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm can exchange tackifier resins in polymer formulations in general, such as tacky polymer formulations and adhesive polymer formulations. A further advantage is that the new formulations have a relatively higher hardness and better strength at elevated temperatures without losing the tackiness for application at room temperature compared to formulations with tackifier resins. This may be because the calcium carbonate particles, unlike tackifier resins, have no softening point or melting point at temperatures where the formulations may be used, such as above 30 degrees Celsius, or within the range of 30-150 degrees Celsius. This is of great importance in many different industries, where such formulations are used as adhesives, coatings, sealants, and elastomers. Furthermore, tackifier resins will typically be hardened or softened by oxidation over time, and their adhesive properties are decreasing. By using calcium carbonate particles according to the present invention instead of tackifier resins in polymer formulations, this unwanted effect is believed to be eliminated. From an environmentally perspective, the present invention can reduce oil based tackifier resin product just by exchanging to calcium carbonate and in this way expect the same useability as a traditional elastomeric sealant.

The solubility of the tackifier resin is highly dependent on the polymer formulation in which it is used. When the maximum soluble amount of tackifier resin is surpassed, the insoluble part of the added tackifier resin will give rise to an enhanced hardness and a reduction in the tackiness of the polymer formulation. This is not an issue when using calcium carbonate particles according to the present invention. Rather, the amount/concentration of calcium carbonate particles according to the present invention can be higher than the amount of tackifier resin for a given formulation, resulting in higher degree of tackiness.

Another surprising effect is that the developed formulations/compositions are particularly good at binding to polyethylene materials, which is normally one of the most difficult materials to bind to.

As used herein, the term “tacky polymer formulation” refers to a physical property of the polymer formulation in which the polymer formulation is sticky when lightly touched. The term "adhesive polymer formulation " used herein refers to a polymer formulation, which exhibits adhesion at normal temperatures (e.g., about 25°C).

One aspect of the present invention relates to a method of applying tackiness or adhesion to a polymer formulation comprising the steps of: a) providing a polymer formulation; and b) mixing calcium carbonate particles having a volume mean grain diameter d5o(vol) of less than 100 nm into said polymer formulation to provide a tacky polymer formulation or an adhesive polymer formulation.

Another aspect of the present invention relates to a method of producing a tacky polymer formulation or an adhesive polymer formulation comprising the steps of: a) providing a polymer formulation; and b) mixing calcium carbonate particles having a volume mean grain diameter d5o(vol) of less than 100 nm into said polymer formulation to provide a tacky polymer formulation or an adhesive polymer formulation.

Yet another aspect of the present invention relates to the use of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm as: a) a substitute for tackifier resin in a tacky or adhesive polymer formulation; or b) a substitute for a part of the tackifier resin in a tacky or adhesive polymer formulation; or c) the sole tackifier in a tacky or adhesive polymer formulation.

Still another aspect of the present invention relates to a tacky polymer composition comprising: i) 1-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1-80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm. Another aspect of the present invention relates to an adhesive polymer composition comprising: i) 1 -90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1 -80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm.

Still another aspect relates to the use of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm as a substitute for a part of or all the tackifier resin present in a tacky or adhesive polymer formulation.

Yet another aspect relates to a tacky or adhesive polymer composition comprising: i) 10-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1 -80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm.

Detailed description of the invention

One aspect of the present invention relates to a method of applying tackiness or adhesion to a polymer formulation comprising the steps of: a) providing a polymer formulation; and b) mixing calcium carbonate particles having a volume mean grain diameter d5o(vol) of less than 100 nm into said polymer formulation to provide a tacky polymer formulation or an adhesive polymer formulation.

In one or more embodiments, said calcium carbonate particles are coated with a fatty acid, such as stearic acid, a silane, phosphoric esters of fatty acids, a siloxane, or mixtures thereof. In one or more embodiments, the amount of said calcium carbonate particles added to said polymer formulation is from 1-80% w/w, such as within the range of 2-75% w/w, e.g., 3-70% w/w, such as within the range of 4-65% w/w, e.g., 5- 60% w/w, such as within the range of 10-55% w/w, e.g., 15-50% w/w, such as within the range of 20-45% w/w, e.g., 25-40% w/w.

In one or more embodiments, said polymer formulation comprises a hydrocarbon polymer having a polyolefin backbone.

In one or more embodiments, said polymer formulation comprises a tackifier resin.

Another aspect of the present invention relates to a method of producing a tacky polymer formulation or an adhesive polymer formulation comprising the steps of: a) providing a polymer formulation; and b) mixing calcium carbonate particles having a volume mean grain diameter d5o(vol) of less than 100 nm into said polymer formulation to provide a tacky polymer formulation or an adhesive polymer formulation.

In one or more embodiments, said calcium carbonate particles are coated with a fatty acid, such as stearic acid, a silane, phosphoric esters of fatty acids, a siloxane, or mixtures thereof.

In one or more embodiments, the amount of said calcium carbonate particles added to said polymer formulation is from 1-80% w/w.

In one or more embodiments, said polymer formulation comprises a hydrocarbon polymer having a polyolefin backbone.

In one or more embodiments, said polymer formulation comprises a tackifier resin. Another aspect relates to a tacky polymer formulation produced by the method according to the present invention.

Yet another aspect relates to an adhesive polymer formulation produced by the method according to the present invention.

Still another aspect of the present invention relates to the use of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm as: a) a substitute for tackifier resin in a tacky or adhesive polymer formulation; or b) a substitute for a part of the tackifier resin in a tacky or adhesive polymer formulation; or c) the sole tackifier in a tacky or adhesive polymer formulation.

In one or more embodiments, said calcium carbonate particles are used as the sole tackifier in a tacky or adhesive polymer formulation.

In one or more embodiments, said calcium carbonate particles are used as a substitute for tackifier resin in a tacky or adhesive polymer formulation.

In one or more embodiments, said calcium carbonate particles are used as a substitute for a part of the tackifier resin in a tacky or adhesive polymer formulation.

Still another aspect of the present invention relates to a tacky polymer composition comprising: i) 1-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1-80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm. Yet another aspect of the present invention relates to a tacky polymer composition consisting of: i) 1-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1-80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm; iii) 1-40% w/w of softener or plasticizer, such as mineral oil, liquid polybutenes, liquid polyacrylates, and lanolin; and iv) 0-40% w/w filler, such as carbon black.

Still another aspect of the present invention relates to a tacky polymer composition consisting of: i) 1-20% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 30-80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm; iii) 1-40% w/w of softener or plasticizer, such as mineral oil, liquid polybutenes, liquid polyacrylates, and lanolin; and iv) 0-40% w/w filler, such as carbon black.

In one or more embodiments, the tacky polymer composition is a sealant composition. In the present context, the term “sealant” is to be understood as a substance used to block the passage of fluids through the surface or joints or openings in materials.

In one or more embodiments, the tacky polymer composition is a coating composition. The term "coating composition" refers to any composition, which can form a coating.

Another aspect of the present invention relates to an adhesive polymer composition comprising: i) 1-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1-80% w/w of calcium carbonate particles having a volume mean grain diameter d5o(vol) of less than 100 nm.

In one or more embodiments, the adhesive polymer composition is a curable adhesive. As is well-known to the skilled person within curable adhesives, the term “curable adhesive” refers to an adhesive composition, which develop bonding properties as a result of curing. The term “curing” refers in the present disclosure to the chemical reactions comprising forming bonds resulting, for example, in chain extension and/or crosslinking of polymer chains. Hence, the adhesive polymer composition may comprise crosslinking agents and/or accelerators/catalysts. It is beyond the scope of this invention to mention the vast amount of different adhesive systems suitable for being charged/set with calcium carbonate according to the present invention.

In one or more embodiments, the adhesive polymer composition is a non-curable adhesive.

Still another aspect relates to the use of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm as a substitute for a part of or all the tackifier resin present in a tacky or adhesive polymer formulation.

Yet another aspect relates to a tacky or adhesive polymer composition comprising: i) 10-90% w/w of a hydrocarbon polymer having a polyolefin backbone; and ii) 1 -80% w/w of calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm.

The value dx represents the diameter relative to which x % of the particles have diameters less than dx. The dx-values may be given in volume or weight percent. The d5o(wt) value is thus the weight median particle size, i.e., 50 wt% of all grains are smaller than this particle size, and the dso(vol) value is the volume median particle size, i.e., 50 vol.% of all grains are smaller than this particle size. Volume median grain diameter dx(vol) was evaluated using a Malvern Mastersizer 3000 Laser Diffraction System or a Sedigraph 5100 or 5120 device from the company Micromeritics, USA. The measured values using a Malvern Mastersizer 3000 Laser Diffraction System, indicates a diameter value such that 50% or 98% by volume, respectively, of the particles have a diameter of less than this value. The raw data obtained by the measurement may be analyzed using the Mie theory, with a particle refractive index of 1.57 and an absorption index of 0.005.

An example of calcium carbonate particles suitable for the present invention may be Viscoexcel®-30 SG from Omya with a d5o(vol) of less than 30 nm, or Viscolite-EL20 from SHIRAISHI KOGYO KAISHA with a d ₅ o(vol) of less than 100 nm.

The morphology of the calcium carbonate particles may be of different shape, such as cubic, spindle, rod, or flake, but the cubic shape may be preferred.

In one or more embodiments, the calcium carbonate particles have a volume mean grain diameter dso(vol) of less than 100 nm, such as within the range of 1- 95 nm, e.g., less than 90 nm, such as within the range of 5-85 nm, e.g., less than 80 nm, such as within the range of 10-75 nm, e.g., less than 70 nm, such as within the range of 15-65 nm, e.g., less than 60 nm, such as within the range of 20-55 nm, e.g., less than 50 nm, such as within the range of 25-45 nm, e.g., less than 40 nm, such as within the range of 30-35 nm, e.g., less than 30 nm.

In one or more embodiments, the calcium carbonate particles have a volume mean grain diameter d9s(vol) of less than 100 nm, such as within the range of 1- 95 nm, e.g., less than 90 nm, such as within the range of 5-85 nm, e.g., less than 80 nm, such as within the range of 10-75 nm, e.g., less than 70 nm, such as within the range of 15-65 nm, e.g., less than 60 nm, such as within the range of 20-55 nm, e.g., less than 50 nm, such as within the range of 25-45 nm, e.g., less than 40 nm, such as within the range of 30-35 nm, e.g., less than 30 nm.

Additionally, in some embodiments, the calcium carbonate particles may have a specific surface area (BET) of at least 40 m ² /g, as measured using nitrogen and the BET method according to ISO 9277, such as within the range of 40-120 m ² /g, e.g., within the range of 45-115 m ² /g, such as within the range of 50-110 m ² /g, e.g., within the range of 55-105 m ² /g, such as within the range of 60-95 m ² /g, e.g., within the range of 65-90 m ² /g, such as within the range of 70-85 m ² /g. The term "specific surface area" (in m ² /g) of the calcium carbonate particles in the meaning of the present invention is determined using the BET method with nitrogen as adsorbing gas, which is well known to the skilled man (ISO 9277:1995). The total surface area (in m ² ) of the calcium carbonate particles is then obtained by multiplying the specific surface area by the mass (in g) of the calcium carbonate particles prior to treatment.

Optionally, certain other ingredients may be added to the polymer formulation of the present invention. Plasticizers or softeners, such as mineral oil, liquid polybutenes, liquid polyacrylates, and lanolin may be added. Fillers, such as kaolin, calcium carbonate, talc, silicates, zinc oxide, titanium dioxide, aluminum hydrate, calcium sulfate, barium sulfate, all with a volume mean grain diameter d5o(vol) within the micron range, clay, and pigments are commonly employed. Antioxidants, such as rubber antioxidants, metal dithiocarbamates, and metal chelating agents may be useful in some applications.

In one or more embodiments, the calcium carbonate particles are coated with a dispersion agent, such as a fatty acid, e.g., stearic acid, a silane, phosphoric esters of fatty acids, or a siloxane. This embodiment has shown to decrease the swelling in the polymer formulations relative to formulations with calcium carbonate particles without coating.

In one or more embodiments, the amount of said calcium carbonate particles used in said polymer formulation is from 1-80% w/w, such as within the range of 2-75% w/w, e.g., 3-70% w/w, such as within the range of 4-65% w/w, e.g., 5-60% w/w, such as within the range of 10-55% w/w, e.g., 15-50% w/w, such as within the range of 20-45% w/w, e.g., 25-40% w/w.

In one or more embodiments, the tackifier resin to be fully or partly substituted is an organic resin, such as e.g., natural resins, synthetic resins, low molecular weight polymers, low molecular weight oligomers, polyisobutylenes, and combinations thereof. Non-limiting examples of organic resins are hydrocarbon resins, typically C5-resins, C9-resins, cycloalifatic hydrocarbon resins, phenolic resins, terpene resins, phenol terpene resins, kumaron-inden resins, and polyisobytylene resin like Oppanol 12.

As used herein, the term “tackifier resin” encompasses organic resins (e.g., natural resins, synthetic resins, and combinations thereof) as well as low molecular weight polymers or oligomers. A low molecular weight polymer or oligomer may be understood as having a weight average molecular weight or Mw of 700-150,000 grams/mole, a Mw of 1000-100,000 grams/mole, or a Mw of 1 ,500-75,000 grams/mole; and/or a Mn of 500- 100,000 grams/mole, a Mn of 700-90,000 grams/mole, or a Mn of 900-50,000 grams/mole. Mw and Mn values referred to herein can be determined by gel permeation chromatography (GPC) calibrated with polystyrene standards. The low molecular weight polymer or oligomer may be selected from polybutene, low molecular weight polyisobutylene, liquid EPDM, liquid or low molecular weight polyisoprene, liquid or low molecular weight styrene-butadiene, liquid or low molecular weight polybutadiene, or a combination thereof.

Liquid EPDMs suitable for use as a tackifer will generally be liquid or flowable at room temperature (23 °C). Suitable liquid EPDMs for use as a tackifer are commercially available, including, but not limited to Trilene® liquid EPDMs from Lion Elastomers (e.g., Trilene® 67, Trilene® 77). The liquid EPDM may have a viscosity of 50,000 to 150,000 centipoise, or 90,000 to 130,000 centipose (Brookfield viscosity, measured at 100°C). The liquid or low molecular weight polyisoprene may have a Mw of 15,000 to 100,000 grams/mole (e.g., 15,000; 20,000; 30,000; 40,000; 50,000; 60,000; 70,000; 80,000; 90,000; 100,000), or 25,000 to 80,000 grams/mole. Liquid or low molecular weight polyisoprenes suitable for use as a tackifer are commercially available, including, but not limited to Isolene® polyisoprenes (e.g., Isolene® 40-S, Isolene® 400-S) from Royal Adhesives & Sealant; DPR® polyisoprenes (e.g., DPR® 35, DPR® 40, and DPR® 75) from DPR Industries, and from Kuraray Co., Ltd. (e.g., LIR-30 and LIR-50).

The liquid or low molecular weight styrene-butadiene may have a Mw of 5,000 to 70,000 grams/mole (e.g., 5,000; 7,500; 10,000; 20,000; 30,000; 40,000; 50,000; 60,000; 70,000) or 7,500 to 50,000 grams/mole. Liquid or low molecular weight styrene-butadienes suitable for use as a tackifier are commercially available, including, but not limited to from Kuraray Co., Ltd. (e.g., L-SBR-820 and L-SBR- 841).

The liquid or low molecular weight polybutadiene may have a Mw of 5,000 to 70,000 grams/mole (e.g., 5,000; 7,500; 10,000; 20,000; 30,000; 40,000; 50,000; 60,000; 70,000) or 7,500 to 50,000 grams/mole. Liquid or low molecular weight polybutadienes suitable for use as a tackifier are commercially available, including, but not limited to from Kuraray Co., Ltd. (e.g., LBR-307, LBR-305, and LBR-352).

The liquid or low molecular weight polybutadiene has a Mw of 5,000 to 70,000 grams/mole (e.g., 5,000; 7,500; 10,000; 20,000; 30,000; 40,000; 50,000; 60,000; 70,000) or 7,500 to 50,000 grams/mole. Liquid or low molecular weight polybutadienes suitable for use as a tackifier are commercially available, including, but not limited to from Kuraray Co., Ltd. (e.g., LBR-307, LBR-305, and LBR-352).

Suitable polybutenes for use as a tackifier are commercially available, including, but not limited to, Indopol® polybutenes from INEOS Oligomers (e.g., H-100, H- 300, H-1500, H-1900). In certain embodiments of the first-fifth embodiments wherein the tackifier includes polybutene, the polybutene has a Mn of 500- 10,000 grams/mole or 500-5,000 grams/mole.

Suitable LMW polyisobutylenes for use as a tackifier are commercially available, including, but not limited to Oppanol® B series polyisobutylenes from BASF (e.g., B10, B15). In certain embodiments of the first-fifth embodiments, wherein the tackifier includes LMW polyisobutylene, the LMW polyisobutylene has a Mn of 20,000 to 100,000 grams/mole, 30,000 to 90,000 grams/mole, or 30,000 to 50,000 grams/mole.

In one or more embodiments, the tacky or adhesive polymer formulation of the present invention further comprises a tackifier resin, preferably a hydrocarbon polymer having a polyolefin backbone. In this way, it will be possible to combine tackifier resins and calcium carbonate particles according to the present invention to obtain a higher tackiness at the maximum concentration of tackifier resin normally used.

In one or more embodiments, the weight ratio between the calcium carbonate particles according to the present invention and the tackifier resin is within the range of 1 :1 -100:1 , e.g., within the range of 5:1 -95:1 , such as within the range of 10:1 -90:1 , e.g., within the range of 15:1 -85:1 , such as within the range of 20:1 - 80:1 , e.g., within the range of 25:1 -75:1 , such as within the range of 30:1 -70:1 , e.g., within the range of 35:1 -65:1 , such as within the range of 40:1 -60:1 , preferably within the range of 1 :1 -50:1 .

It should be noted that embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects of the invention.

As used in the specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" or "approximately" one particular value and/or to "about" or "approximately" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about", it will be understood that the particular value forms another embodiment.

The invention will now be described in further details in the following non-limiting examples.

Examples

Proof of concept

The main object of this study was to provide documentation that that calcium carbonate particles having a volume mean grain diameter dso(vol) of less than 100 nm can exchange tackifier resins in polymer formulations in general.

The examples are not intended to be limiting to the scope of the invention, as the core of the invention may be used for many different applications.

Formulations 1 , and 2 are compounded according to table 1 , where the amount is shown in weight%. The volume % of tackifier is the same for the two formulations, but the weight % is different. All other ingredients are the same.

The tackifier resin is a synthetic cycloalifatic hydrocarbon resin with a glass transition temperature of 52° Celsius and a softening point of 103 +/- 3 degrees Celsius.

Table 1.

Needle penetration according to ISO 2137 Formulation 1

20° Celsius: 48 mdm

50° Celsius: 105 mdm

Formulation 2 20° Celsius: 50 mdm

50° Celsius: 90 mdm

Formulation 2 performs much better than Formulation 1 at 50° Celsius as it softens less.

Tensile and peel tests

Tensile and peel tests are performed after application of the formulation to a polypropylene sheet material in a thickness of 2.0 +/- 0.2 mm.

Formulation 1 - tensile test 23° Celsius: 1.8 N/mm 50° Celsius: 0.97 N/mm 80° Celsius: 0.80 N/mm

Formulation 2 - tensile test 23° Celsius: 1.9 N/mm 50° Celsius: 1.03 N/mm 80° Celsius: 0.81 N/mm

Formulation 2 performs slightly better than Formulation 1 at all tested temperatures.

Formulation 1 - peel test 24° Celsius: 1.1 N/mm

Formulation 2 - peel test 24° Celsius: 1.1 N/mm

Formulation 2 performs equal to Formulation 1 at room temperature.

Swelling

Swelling is tested in distilled water at room temperature. After one week, Formulation 1 had increased its volume by 0.6%, while Formulation 2 only increased by 0.2%. After four weeks, Formulation 1 had increased its volume by 0.8%, while Formulation 2 only increased by 0.4%. nano CaCC and tackifier resin

Table 2. The amounts are shown in weight%

The results show that it will not be possible to use a higher concentration of tackifier resin than 25-30% w/w, due to solubility and/or mixability issues. The mixing must be made at relatively higher temperature when formulations include tackifier resin and the mixing time will be longer. As an example, the mixing time for F300 is only half of the mixing time needed for FR100.

A combination of calcium carbonate with a dso(vol) = 30 nanometres and tackifier resin will give an extremely high relative tackiness, and the possibilities of blending tackifier resin and calcium carbonate with a dso(vol) less than 100 nanometres in various combinations may improve the tackiness of known formulas. Flence, the present invention allows for finetuning the tackiness in a formulation merely by varying the amounts of different types of calcium carbonates with different mean particle sizes.

Formulations 3-7 are compounded according to Table 3, where the amount is shown in weight%.

Formulations 3, 4, 5, 6, and 7

Different types of calcium carbonates with or without added stearic acid as surface coating are mixed into the formulations. The examples are used to show that the use of calcium carbonate according to the present invention can partly or fully exchange the use of organic tackifiers, and at the same time allow for a relatively higher tack. Another interesting aspect is that micron size calcium carbonate particles coated with stearic acid prevents the formulation from being properly mixed, while formulations with nano size calcium carbonate particles coated with stearic acid decreases the mixing time relative to conventual organic tackifiers. It may therefore be speculated that nano calcium carbonate particles without stearic acid is even better, i.e., further decreases the mixing time and/or increases the tackiness. Such calcium carbonates may be obtained under the trade name 1951 RH from SkySpring Nanomaterials Inc., United States, having an Average Particle Size of 15-40 nm. Surface treated variants, e.g., 1956RH or 1953RH, may also be purchased and have a Specific Surface Area (m ² /g) of more than 40.

Table 3. The amounts are shown in weight% Formulations 8 and 9 in table 4:

See table 4 for the comparison of a standard sealant formulation, which is used to joint together polyethylene films, compared to the new formulation without organic tackifiers.

Table 4. The amounts are shown in weight%

Surprisingly, more simple formulations based on nano-calcium carbonate as tackifier can be made with the same processability as standard formulations with organic tackifiers. It is easy to reach the same bond strength with nano-calcium carbonate, and surprisingly it is also possible to reach higher levels of bond strength without the use of organic tackifiers. It is also expected that formulations with both nano-calcium carbonate and organic tackifiers can be formulated to even higher levels of bond strength.

Furthermore, is also surprising that the processability of such formulations are the same or better compared to a standard formulation. This allows the chemist to add relatively higher concentrations of elastomer into formulations without damaging the processability. It has been shown that it is possible to make a formulation based only on three raw materials; elastomer (e.g., EP(D)M, Butyl, Polyisobutylene, Poly-alfa-olefins, TPO (Thermoplastic Polyolefins), or the like), filler (which must include a percentage of nano-calcium carbonate, possibly coated with e.g., stearic acid), and oil as softener/plasticizer (e.g., polyisobutylene oil, paraffinic oil, or other compatible oil). These materials are already known as materials for use in contact with Food, Pharma, and Medical products without any concerns. This formulation gives the same high adhesiveness and bond strength compared to standard formulations, and even more surprisingly, the processability (such as mixing and extrusion) is on same level or better compared to standard formulations. Hence, this will give the possibility to offer this kind of formulations as food, pharma, and medical contact materials. Based on the above, it can be expected that all types of polymer formulations will give the same kind of results. Additionally, environmentally friendly new formulations can be made much simpler, since the number of different types of raw materials can be reduced, leading to a higher toxicological purity in production and in end use. The processability by mixing and extrusion into a sealant is possible for both formulations 8 and 9, but it is much easier to mix the new formulation 9. Only three high purity raw materials are needed for the new formulation 9, compared to nine raw materials in formulation 8.

In this way it is much simpler to formulate formulation 9, which can be easily re formulated, i.e., further developed, to give even higher performance in usability compared to the existing standard formulation 8.