The present invention discloses halogen free flame retardant polymeric compositions comprising modified layered double hydroxide nanofiller (LDH) with excellent mechanical properties, fire/flame retardancy, multifunction, thermal resistance, low smoke release and good processability and their procedure for obtainment. Moreover, the present invention relates to new modified LDH nanofillers based on an organically functionalization, concretely a series of multifunctional LDHs, and the procedure for obtainment of the halogen free flame retardant polymeric compositions comprising the new modified LDH nanofillers. Furthermore, the present invention relates to articles comprising halogen free flame/fire retardant polymeric composition and their uses an electric or electronic circuit component, a structural element for transportation and building or an indoor everyday object. BACKGROUND ART

Layered double hydroxide (LDH) is a host-guest material consisting of positively charged metal hydroxide sheets with intercalated anions and water molecules. It can be represented by a general formula, [M ²⁺ i _-x M ³⁺ _x (OH) ₂ ] ^x+ A _n yH ₂ 0, wherein M ²⁺ is a divalent metal ion such as Zn ²⁺ , Mn ²⁺ , Ni ²⁺ , Co ²⁺ , Fe ²⁺ , Cu ²⁺ , Sn ²⁺ , Ba ²⁺ , Ca ²⁺ , Mg ²⁺ , M ³⁺ is a trivalent metal ion such as Al ³⁺ , Cr ³⁺ , Fe ³⁺ , Co ³⁺ , Mn ³⁺ , Ni ³⁺ , Ce ³⁺ , and Ga ³⁺ , A" ^" is representing interlayer anions, such as CO3 ^2" , CI ^" and N03 ^" and y has a value in the range of from 0 to 10.

One of the most recent applications which is being currently extensively investigated is the use of LDHs as nanofillers of polymer matrices, to improve flame-retardancy and mechanical properties [F.R. Costa, U. Wagenknecht,and G. Heinrich, Polym. Degrad. Stab. 2007, 92, 1813; C. Manzi-Nshuti, J.M. Hossenlopp and C.A. Wilkie, Polym. Degrad. Stab. 2008, 93, 1855] Nevertheless, a modification of the LDHs is necessary to use them as nanofillers of polymer matrices.

Current methods employed for modification of LDH based on ion exchange, regeneration, in-situ synthesis or enzymatic processes are well known and can be easily found in the literature [D. G. Evans and X. Duan, Chemical Communications, 2006, 485; US7786202; US7968740 and EP2540770A2]. However, the obtained modified LDH have low or limited efficiency on improving the fire/flame retardancy and other properties such as mechanical, thermal stability of polymeric materials. Flammability is one of the most important weaknesses for most of the obtained polymeric materials.

LDH with 2-dimensional, platelet-like nanostructures has been suggested as the ideal environmental friendly fire retardant since it could improve the fire/flame retardancy, mechanical properties, thermal stability, barrier properties of polymer matrices when working as nanofillers. However, the currently available modified LDH shows limited function, low flame retardant efficiency and low mechanical reinforcement.

For the reasons stated above, it is needed to develop new environmental friendly flame retardant polymeric compositions with excellent fire/flame retardancy and thermal resistance, multifunction, superior mechanical properties and low smoke release.

SUMMARY OF THE INVENTION The present invention discloses halogen free flame retardant polymeric compositions comprising modified layered double hydroxide nanofiller (LDH) with excellent mechanical properties, multifunction, thermal resistance, fire/flame retardancy, low smoke release and good processability and their procedure for obtainment.

Moreover, the present invention relates to new modified LDH nanofillers based on an organically functionalization, concretely a series of multifunctional LDHs, and the procedure for obtainment of the halogen free flame retardant polymeric compositions comprising the new modified LDH nanofillers.

Using the new modified LHD nanofillers fire/flame retardant efficiency is improved in a 10-50% in respect to the unmodified LDHs compositions and mechanical properties is improved in a 10-1 10% in respect to the unmodified LDHs compositions.

The invention is not limited to a specific kind of a polymer matrix; modified LDHs can be incorporated in thermoplastics, thermosets and rubber systems.

The present invention can be used to produce excellent polymeric materials which combine synergistically good processability and performance, high fire/flame retardancy, low smoke release and mechanical and thermal properties.

Furthermore, the present invention relates to articles comprising halogen free flame/fire retardant polymeric composition and their uses an electric or electronic circuit component, a structural element for transportation and building or an indoor everyday object.

Moreover, the present invention relates to the use of the halogen free flame/fire retardant thermoset polymeric composition as an adhesive. Therefore, a first aspect of the present invention relates to a flame retardant halogen free polymeric composition that comprises the following components: • at least polymeric matrix selected from the list consisting of thermoset polymers, thermoplastic polymers and rubbers;

• and at least one modified layered double hydroxide nanofiller in a weight percent between 0.5 % and 70 % based on the weight of the total composition.

Any person skilled in the art knows the meaning of a modified layered double hydroxide nanofiller, as described in the background art. In a preferred embodiment of the invention, the composition described above, additionally comprises at least one flame retardant phosphorous compound in a weight percent between 0.5 % and 40 % based on the weight of the total composition. Any thermoset polymer known by a person skilled in the art can be used as thermoset polymer in the composition according to the invention. Nevertheless, in another preferred embodiment of the invention, the thermoset polymers which can be included in the composition of the invention are selected from the list consisting of phenolic resins, epoxy resins, unsaturated polyesters and a combination thereof.

More preferably, the composition additionally comprises at least one hardener in a stoichiometric relation, based on the weight of the total composition, which comprises an amine group, an anhydride group, an aryl group, a sulfhydryl group or a combination thereof.

The hardener of the epoxy resin matrix preferably comprises an aryl group. More preferably, the hardener is selected from the list comprising aminophenyl sulfone (DDS), diaminodiphenylmethane (DDM) and a combination thereof. In another preferred embodiment of the invention, the hardener is in a weight percent between 10 and 40% based on the total weight of the cured composition. In another preferred embodiment of the invention, the modified layered double hydroxide nanofiller is in a weight percent between 0.5 % and 30 % based on the weight of the total composition, when a thermoset is included in the composition of the invention. More preferably, in a weight percent between 0.5 % and 15 % based on the weight of the total composition.

Any thermoplastic polymer known by a person skilled in the art can be used as thermoplastic polymer in the composition according to the invention, however, in another preferred embodiment of the invention, the thermoplastic polymers which can be included in the composition of the invention are selected from the list consisting of polyester, polycarbonate, polyamide, a polyolefin, and a combination thereof. More preferably, the thermoplastic polymers are selected from the list consisting of polyethylene terephthalate (PET), polylactic acid (PLA), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN) and polybutylene naphthalate (PBN).

In another preferred embodiment, the thermoplastic polymer is a block copolyester. Suitable block copolyesters may comprise hard polyester segments chosen from the aforementioned group, and soft polyester segments derived from at least a polyether or an aliphatic polyester. Examples of suitable polyolefins and various styrene polymers are polypropylene, polyethylene, propylene copolymers with ethylene, vinyl acetate, butadiene and/or other monomers which produce a variety of polyolefin polymers. Ethylene homopolymers and copolymers, rubbers and other hydrocarbon polymers are further examples. Particularly preferred polyolefins include polyethylenes, polypropylenes and copolymers thereof or with other olefinic monomers such as butene-l, isobutylene, acrylic acids, esters of acrylic acids, vinyl acetate and the like or combinations thereof and/or blends of these polymers and copolymers. Styrene polymers include polystyrene, substituted polystyrene and impact modified polystyrene containing rubber such as butadiene. Also included are acrylonitrile butadiene styrene and other styrene containing copolymers. Examples of a suitable polyamide are aliphatic polyamides, for example PA-6, PA-6,6, PA-9, PA-11 , PA-4,6, polyamides based on 2- methylpentamethylene diamine and adipic acid and copolyamides thereof, semi-aromatic polyamides based on aromatic dicarboxylic acids, for example isophthalic acid and terephthalic acid, and aliphatic diamines. In another preferred embodiment of the invention, the modified layered double hydroxide nanofiller is in a weight percent between 0.5 % and 55 % based on the weight of the total composition, when a thermoplastic is included in the composition of the invention.

Any rubber or cured or vulcanized precursor rubber known by a person skilled in the art can be used as rubber in the composition according to the present invention, however, in another preferred embodiment of the invention, the rubbers which can be included in the composition of the invention are selected from the list consisting of natural rubber (NR), styrene-butadiene rubber (SBR) polyisoprene (IR), polybutadiene or butyl rubber (BR), polyisobutylene rubber (HR), nitrile butadiene rubber (NBR), styrene-isoprene-styrene (SIS), styrenic block copolymers (SBS), silicone rubbers (Q), ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), ethylene-vinylacetate rubber (EVA), vinyl butadiene rubber, polyacrylic rubbers (ACM), polynorbornene (PNR), polyurethanes and polyester/ether thermoplastic elastomers and a combination thereof. More preferably, the rubber is selected from NR, SBR, EPDM, HR, BR and Q.

In another preferred embodiment of the invention, the modified layered double hydroxide nanofiller is in a weight percent between 0.5 % and 70 % based on the weight of the total composition when a rubber is included in the composition of the invention. In another preferred embodiment of the present invention, the layered double hydroxide is modified with at least one unit selected from the list consisting of:

• -H;

. -H+;

• an alkaline metal ion M ⁺¹ ;

• an alkyl(Ci-C5o) group;

• an -0-alkyl(Ci-C5o) group;

• a -X group consisting of S0 ₃ ^" , S0 ₄ ^" , P0 ₃ ^2" , COO ^" , HPO ₄ ^2" , H ₂ PO ₄ ^" , and PO ₄ ³ - ;

• an -alkyl(Ci-C ₅ o)-X group;

• a -X-Ri group, wherein Ri is independently selected from -H ⁺ and an alkaline metal ion M ⁺¹ ;

• a 1 , 3, 5 - triazine group of formula I

[I]

wherein

R ₂ , R3 and R ₄ are independently selected from the groups consisting of an -alkyl(Ci-C5o)-Xi group, an -aryl(C6-Cie)-Xi group, an -X ₂ -alkyl(Ci-C ₅ o)-Xi group, an -X ₂ -aryl(C ₆ -Ci ₈ )-Xi group wherein -Xi is SO ₃ ^" , SO ₄ ^" , PO ₃ ^2" or COO ^" and -X ₂ is SO ₃ , -SO ₄ , PO ₃ ^" , - NH- and COO.

• a cyclodextrin group of formula II

having n values are 6, 7 or 8 and wherein

R ₅ , R6 and R ₇ are independently selected from an -alkyl(Ci- C50)- X ₃ group, an -aryl(C ₆ -Ci ₈ )-X3 group, an -X ₂ -alkyl(Ci-C ₅ o)- X3 group, wherein -X ₃ is selected from S0 ₃ ^" , S0 ₄ ^" , PO3 ^2" ' COO ^" , -OH, -NH ₂ or epoxy group, and -X ₂ is SO ₃ , -SO ₄ , PO ₃ ^" , -NH- and COO. a group of formula III

[III] having n and m values between 1 and 50 independently and wherein X ₄ is selected from O ^" and COO ^" ; a group of formula IV

wherein

Ra is selected from O ^" , -R9COO ^" wherein R ₉ is selected from aryl(Ci-Ci ₈ ), an -X ₅ -aryl(C ₆ -Ci8)-X6 group wherein -X ₅ is selected from is SO ₃ , -SO ₄ , PO ₃ ^" , -NH- and COO, and -X ₆ is selected from SO ₃ ^" , SO ₄ ^" ,PO ₃ ^2~ or COO ^" ;

R10 is selected from

wherein R , R ₁₂ , R13, RH, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci-C5o), - alkenyl(C ₂ -C5o), an aryl(C6-Cis) and -OH,

an group of formula V

[V] having x values of 0 and 1 , z values between 1 and 50 and wherein X ₇ and Xs are independently selected from COO ^" and O ^" ; group of formula VI

[VI];

• a phytic acid;

• an group of formula VII

[VII] wherein

R20, R21 , R22, R23, R24, R25, R26 and R27 are independently selected from a -X group consisting of SO ^3" , SO ₄ ^" , PO3 ^2" and COO ^" , and an -alkyl(Ci-C ₅ o)-X9 group,

R ₂ 8 is independently selected from -O- and-S-, and

R ₂ 9 is selected from an -alkyl(Ci-C5o)-Xio group, wherein -X ₉ and -X10 is selected from SO ₃ ^" , SO ₄ ^" , PO ₃ ^2" and COO ^" ;

• a group of formula VIII

[VIII]

having y values between 0 and 50 and wherein

R ₃ o and R31 are independently selected from -H, an alkyl(Ci- C ₅₀ ) group, an -O-alkyl(CrC ₅₀ ) group and an aryl (C ₆ -Ci ₈ ) group and

R32 and R33 are independently selected from an anionic alkyl(Ci-C5o) group, an anionic -0-alkyl(Ci-C5o) group, an

anionic aryl (C ₆ -Ci ₈ ) group and an anion of formula IX

[IX]

wherein -Ph is a phenyl group; an group of form

[X] having 0 and p values between 0 and 10 independently and wherein R35, R36, R37 and R ₃ 8 are independently selected from a hydrogen, an alkyl(Ci-C5o) group, an -0-alkyl(Ci-C5o) group and an aryl(C6-Cis) group, and

R34 are independently selected from an Y group consisting of a compound of formula XI

R36

[XI] and a -3,5-triazine group of formula XII

[XII]

wherein Rsg and R40 are independently selected from -H, -R ₃₅ and an -Y group consisting of a compound of formula XI.

In the present invention, the term "alkaline metal ion M ⁺¹ " relates to an alkali metal ion selected from the group consisting of Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , and Cs ⁺ . The term "alkyl (C1 -C50)" as used herein relates to a linear or branched aliphatic chains, preferably containing one to fifty carbon atoms. As used herein the designation Cx-Cy, wherein x and y are integers, denotes a group name from x to y carbon atoms, e.g., a C1-C4 alkyl group is an alkyl group having one to four carbon atoms. Nonlimiting examples of alkyl groups include, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl (2-methylpropyl), and t-butyl (1 ,1 -dimethylethyl).

The term "alkenyl (C2-C50)" " as used herein is defined identically as "alkyl" except for containing a carbon-carbon double bond.

The term "-O-alkyl (C1-C50)" as used herein relates to a linear or branched aliphatic chain, an alkyl group, preferably containing one to fifty carbon atoms, which is bonded to an oxygen atom.

In the present invention, the term "— X _a -alkyl (C C5o)-X _b " as used herein relates to a linear or branched aliphatic chain, an alkyl group, preferably containing one to fifty carbon atoms which is substituted by a -X _a and a -X _b groups wherein a and b are integers.

In the present invention, the term "aryl" relates to an aromatic carbocyclic chain, which has from 6 to 18 carbon atoms, and can be a single or multiple ring, in this last case with separated and/or condensed rings. In the present invention, preferably the aryl group is a phenyl. Non-limiting examples of aryl grupos are phenyl, naphthyl and indenyl groups.

In the present invention, the term "epoxide" relates to is cyclic ether with three ring atoms. As a functional group, epoxides feature the epoxy prefix, such as in the compound 1 ,2-epoxycycloheptane, which can also be called cycloheptene epoxide, or simply cycloheptene oxide.

In a preferred embodiment, the layered double hydroxide is modified with 1 to 20 units. The units can be different or the same. In another preferred embodiment, the layered double hydroxide is modified with at least 2 units. The units can be different or the same. Each unit interacts with the layered double hydroxide by ion exchange; therefore, as the present invention relates to the possibility of using more than one unit, multifunctional LDHs are obtained in the present invention. In another preferred embodiment, the layered double hydroxide is modified with at least one unit of a cyclodextrin group of formula [II] combined with or forming an inclusive compound with at least one unit of the rest of the modifiers units. More preferably, the layered double hydroxide is modified with 6, 7 or 8 units of a cyclodextrin group of formula [II].

In the present invention, the functionalized cyclodextrin can interact in two different ways with the layered double hydroxide. It can interact directly by ion exchange or can form inclusion compounds which interact with the layered double hydroxide by an ion exchange. In host-guest chemistry an inclusion compound is a complex in which one chemical compound (the "host") forms a cavity in which molecules of a second "guest" compound are located. Cyclodextrin is an excellent host to form inclusion compounds. In the present invention, cyclodextrin can act as host of one of the functional modifiers selected from the previously mentioned list forming an inclusion compound which can interact with the layered double hydroxide nanofiller by ion exchange.

In a preferred embodiment of the present invention, the layered double hydroxide of the flame retardant composition as described previously is modified with at least one unit of a 1 , 3, 5 - triazine group of formula [I] alone or in combination with at least one unit of the rest of the modifiers units, wherein R2, R3 and R ₄ are an -X ₂ -aryl(C6)-Xi group wherein X ₂ is -NH- and Xi is SO ^3" .

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of a 1 , 3, 5 - triazine group of formula [I] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₂ , R3 and R ₄ are an - X ₂ -alkyl(C5)-Xi group wherein X ₂ is -NH- and Xi is COO ^" . More preferably, the layered double hydroxide nanofiller is modified with one unit of a 1 , 3, 5 - triazine group of formula [I] wherein R ₂ , R ₃ and R ₄ are an -X ₂ -alkyl(C5)-Xi group wherein X ₂ is -NH- and Xi is COO ^" , combined with one unit of a cyclodextrin group of formula [II].

Another preferred embodiment of the present invention relates to the layered double hydroxide of the composition as described previously that is modified with one unit of a 1 , 3, 5 - triazine group of formula [I] wherein R ₂ , R ₃ and R ₄ are an -X ₂ -alkyl(C5)-Xi group wherein X ₂ is -NH- and Xi is COO ^" , combined with two units of a cyclodextrin group of formula [II].

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [III] alone or in combination with at least one unit of the rest of the modifiers units, wherein X ₄ is O ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [III], wherein X ₄ is O ^" .

Another preferred embodiment of the present invention relates to the layered double hydroxide that is modified with one unit of the group of formula [III] wherein X ₄ is O ^" combined with one unit of a cyclodextrin group of formula [II]. Another preferred embodiment of the present invention relates to the layered double hydroxide that is modified with three units of the group of formula [III] wherein X ₄ is O ^" combined with one unit of cyclodextrin group of formula [II].

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [III] alone or in combination with at least one unit of the rest of the modifiers units, wherein X ₄ is wherein X ₄ is COO ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [III], wherein X4 is wherein X4 is COO ^" .

Another preferred embodiment of the present invention relates to the layered double hydroxide of the composition as described previously that is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is an -NH-aryl(Ce)- SO3 ^" group and R10 is

wherein Rn, R12, R13, Ri4, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci-C5o), -alkenyl(C2-C5o), an aryl (C-6-Cie) and -OH . More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein R ₉ is an -NH-aryl(C6)-SO3 ^~ group and R10 is

wherein Rn, Ri ₂ , R13, Ri4, R15, R16, R17, R18 and Rigare independently selected from an -alkyl(Ci-C5o), -alkenyl(C ₂ -C5o), an aryl (C6-Cis) and -OH. In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is a O ^" group and R10 is

wherein Rn , Ri ₂ , R13, Ri4, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci -C5o), -alkenyl(C ₂ -C5o), an aryl (C6-Cis) and -OH. More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein R ₉ is a O ^" group and R10 is

wherein Rn , Ri ₂ , R13, Ri4, R15, R16, R17, R18 and Rig are independently selected from an -alkyl(Ci-C5o), -alkenyl(C ₂ -C5o), an aryl (C-6-Cie) and -OH.

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is a COO ^" group and R10 is

OO ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein R ₉ is a COO ^" group and R10 is

coo-

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is an O ^" group and R10 is

coo- More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein Rg is an O ^" group and R10 is

coo-

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is an O ^" group and R10 is

More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein Rg is an O ^" group and R10 is

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [IV] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₉ is an COO ^" group and R ₁ 0 is

coo-

More preferably, the layered double hydroxide is modified with one unit of the group of formula [IV], wherein R ₉ is an COO ^" group and Rio is

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [V] alone or in combination with at least one unit of the rest of the modifiers units, having a z value of 1 and wherein X ₇ and Xs are O ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and X ₈ are O ^" .

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [V] alone or in combination with at least one unit of the rest of the modifiers units, having a z value of 1 and wherein X ₇ and X ₈ are COO ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and X ₈ are COO ^" .

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified is modified with at least one unit of the group of formula [V] alone or in combination with at least one unit of the rest of the modifiers units, having a z value of 1 and wherein X ₇ and Xs are O ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and Xs are O ^" .

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of the group of formula [V] alone or in combination with at least one unit of the rest of the modifiers units, having a z value of 0 and wherein X ₇ and Xs are COO ^" . More preferably, the layered double hydroxide is modified with one unit of the group of formula [V], having a z value of 0 and wherein X ₇ and Xs are COO ^" . In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with at least one unit of a cyclodextrin group of formula [II], at least one unit of an -alkyl(d- C5o)-X group wherein the X group is consisting of SO3 ^" , SO ₄ ^" , PO3 ^2" and COO ^" ; and at least one group of formula [VI]. More preferably, the -alkyl(Ci-C5o)-X is alkyl(C ₄ )-SO ₃ ^" .

In another preferred embodiment of the present invention, the layered double hydroxide of the composition as described previously is modified with one unit of phytic acid and one unit of a cyclodextrin group of formula [II].

A second aspect of the present invention relates to the process of obtaining the flame retardant composition describes above. The process referring to the use of thermosets matrices comprises following steps: a) mixing at least one thermoset matrix and at least a hardener at a temperature value between 60 and 150°C,

b) optionally adding at least one flame retardant phosphorous compound c) adding at least one modified layered double hydroxide nanofiller to the mixture of step (a) or (b),

d) transferring the mixture obtained in step (c) into a mold, and

e) curing the mixture inside a mold of step (d) at least once at a temperature value between 120 and 220°C.

In a preferred embodiment, the curing step (e) is carried out in one step at a temperature of 180 °C and maintaining said temperature for 2 hours.

In another preferred embodiment, the curing step (e) is carried out in three- steps at temperatures values between 120°C and 220°C and maintaining said temperature for between 30 and 150 minutes. More preferably, the curing step (d) is carried out by following continuously the next three steps: i) curing the mixture obtained in step (e) at a temperature of 150 °C and maintaining the temperature for 1 hour,

ii) curing the mixture obtained in (ii) at a temperature of 180 °C and maintaining the temperature for 2 hours, and

iii) curing the mixture obtained in (iii) at a temperature of 200°C and maintaining the temperature for 1 hour.

The process referring to the use of thermoplastic matrices comprises following steps: a) adding at least one modified layered double hydroxide toat least one thermoplastic matrix or to a mixture of at least one thermoplastic matrix and at least one flame retardant phosphorous compound,

b) extruding the mixture obtained in (a) at a temperature ranging between 50 and 300 °C.

More preferably, the extrusion of step b) is performed by two-screw extruder via injection mould. The process referring to the use of rubber matrices comprises following steps: a) adding at least one modified layered double hydroxide to at least one rubber matrix or to a mixture of at least one rubber matrix and at least one flame retardant phosphorous compound,

b) molding the mixture of step (a) at a temperature ranging between 10 and 100 °C.

More preferably, the molding of step b) is performed by a two-roll machine via hot press.

A third aspect of the present invention relates to an article comprising the composition described previously.

A fourth aspect relates to an article coated by the composition of the present invention.

In another preferred embodiment of the present invention, the article is an electric or electronic circuit component, a structural element for transportation and building or an indoor everyday object. In the present invention the term "transportation" refers to aircrafts, ships, rails, cars, bicycles and the like and the term "building" relates to any structural element forming any kind of building. Furthermore, the term indoor everyday object- refers to any object taking part of the indoor decoration of a building referring to indoor furniture such as the furniture of a living room, a kitchen, a dining room, an office and the like.

More preferably, the article is an electric or electronic circuit component having an insulating coating of the composition of the present invention.

In another preferred embodiment of the present invention, the composition comprising a thermoset matrix is used as adhesive. A sixth and last aspect of the present invention relates to a modified layered double hydroxide, wherein said modified layered double hydroxide is modified with at least one unit selected from the list consisting of:

• a 1 , 3, 5 - triazine group of formula I

wherein

R2, R3 and R ₄ are independently selected from the groups consisting of an -alkyl(Ci -C5o)-Xi group, an -aryl(C6-Cie)-Xi group, -X ₂ -alkyl(Ci -C5o)-Xi group, an -X ₂ -aryl(C6-Cie)-Xi group wherein -X^ is S0 ₃ ^" , S0 ₄ ^" , P0 ₃ ^2" or COO ^" and -X ₂ is SO ₃ , -SO ₄ , NH- and COO; having n values are 6, 7 or 8 and wherein

R ₅ , R6 and R ₇ are independently selected from an -alkyl(Ci- C50)- X ₃ group, an -aryl(C ₆ -Ci ₈ )-X ₃ group, an -X ₂ -alkyl(Ci-C ₅ o)- X3 group, wherein -X ₃ is selected from SO ₃ ^" , SO ₄ ^" , PO ₃ ^2"■ COO ^" , -OH, -NH ₂ or epoxy group, and -X ₂ is SO ₃ , -SO ₄ , PO ₃ ^" , -NH- and COO; a group of formula III

[III] having n and m values between 1 and 50 independently and wherein X ₄ is selected from O ^" and COO ^" ; a group of formula IV

[IV]

wherein

R ₈ is selected from O ^" , -R ₉ COO ^" wherein R ₉ is selected from aryl(Ci-Ci ₈ ), an -X ₅ -aryl(C ₆ -Ci8)-X6 group wherein -X ₅ is selected from is SO ₃ , -SO ₄ , PO ₃ ^" , -NH- and COO, and -X ₆ is selected from SO ₃ ^" , SO ₄ ^" ,PO ₃ ^2~ or COO ^" ;

Rio is selected from

wherein R , R ₁₂ , R13, RH, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci-C5o), - alkenyl(C ₂ -C5o), an aryl(C6-Cis) and -OH,

an group of formula V

[V]

having x values of 0 and 1 , z values between 1 and 50 and wherein X ₇ and Xs are independently selected from COO ^" and O ^" ; In a preferred embodiment, the modified layered double hydroxide previously described is additionally modified with at least one unit selected from the list consisting of:

• -H;

. -H+;

• an alkaline metal ion M ⁺¹ ;

• an alkyl(Ci-C ₅₀ ) group;

• an -0-alkyl(Ci-C5o) group;

• a -X group consisting of S0 ₃ ^" , S0 ₄ ^" , P0 ₃ ^2" , COO ^" , HPO ₄ ^2" , H ₂ PO ₄ ^" , and PO ₄ ³ - ;

• an -alkyl(Ci-C5o)-X group;

• a -X-Ri group, wherein Ri is independently selected from -H ⁺ and an alkaline metal ion M ⁺¹ ;

• a group of formul

[VI]; a phytic acid;

an group of form

[VII] wherein

R20, R21 , R22, R23, R24, R25, R26 and R27 are independently selected from a -X group consisting of SO ^3" , SO ₄ ^" , PO3 ^2" and

COO ^" , and an -alkyl(CrC ₅ o)-X9 group,

R28 is independently selected from -O- and-S-, and

R29 is selected from an -alkyl(Ci-C5o)-Xio group, wherein -X ₉ and -X10 is selected from SO ₃ ^" , SO ₄ ^" , PO ₃ ^2" and COO ^" ;

• a group of formula VI I I

[VI I I]

having y values between 0 and 50 and wherein

R ₃ o and R31 are independently selected from -H, an alkyl(Ci - C50) group, an -O-alkyl(Ci-C5o) group and an aryl (C-6-Cie) group and

R32 and R33 are independently selected from an anionic alkyl(Ci-C5o) group, an anionic -O-alkyl(Ci-C5o) group, an

anionic aryl (C-6-Cie) group and an anion of formula IX

[IX]

wherein -Ph is a phenyl group;

• an group of formula X

[X] having o and p values between 0 and 10 independently and wherein R35, R36, R37 and R ₃ 8 are independently selected from a hydrogen, an alkyl(Ci-C5o) group, an -0-alkyl(Ci-C5o) group and an aryl(C6-Cis) group, and

R34 are independently selected from an Y group consisting of a compound of formula XI

R36

[XI] and a -3,5-triazine group of formula XII

wherein R ₃₉ and R ₄₀ are independently selected from -H, -R ₃₅ and an -Y group consisting of a compound of formula XI .

In a preferred embodiment of the invention, the modified layered double hydroxide described before comprises between 1 and 20 units of the list. The units can be different or the same.

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises at least 2 units of the list. The units can be different or the same.

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises at least one unit of a cyclodextrin group of formula [II] combined with or forming an inclusive compound with the rest of the modifiers units. More preferably, comprises 6, 7 or 8 units of a cyclodextrin group of formula [I I].

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises at least one unit of a 1 , 3, 5 - triazine group of formula [I] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₂ , R3 and R ₄ are an -X ₂ -aryl(Ce)-Xi group wherein X ₂ is -NH- and Xi is SO ^3" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises at least one unit of a 1 , 3, 5 - triazine group of formula [I] alone or in combination with at least one unit of the rest of the modifiers units, wherein R ₂ , R ₃ and R ₄ are an -X ₂ -alkyl(C5)-Xi group wherein X ₂ is -NH- and Xi is COO ^" . More preferably, comprises one unit of a 1 , 3, 5 - triazine group of formula [I] wherein R ₂ , R ₃ and R ₄ are an -X ₂ -alkyl(C5)-Xi group wherein X ₂ is -NH- and Xi is COO ^" , combined with one unit of a cyclodextrin group of formula [I I]. In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of a 1 , 3, 5 - triazine group of formula [I] wherein R ₂ , R3 and R ₄ are an -X ₂ -alkyl(C5)-Xi group wherein X ₂ is - NH- and Xi is COO ^" , combined with two units of a cyclodextrin group of formula [II].

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [III] alone or in combination with at least one unit of the rest of the modifiers units, wherein X ₄ is O ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [III] wherein X ₄ is O ^" combined with one unit of a cyclodextrin group of formula [II].

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises three units of the group of formula [III] wherein X ₄ is O ^" combined with one unit of a cyclodextrin group of formula [II]. In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [III], wherein X ₄ is wherein X ₄ is COO ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein R ₉ is an -NH-aryl(C ₆ )-SO ₃ ^" group and R10 is

wherein Rn , Ri ₂ , R13, Ri4, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci -C5o), -alkenyl(C ₂ -C5o), an aryl (C6-Cis) and -OH, In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein Rg is a O ^" group and R10 is

wherein Rn , Ri ₂ , R13, Ri4, R15, R16, R17, R18 and R19 are independently selected from an -alkyl(Ci -C5o), -alkenyl(C ₂ -C5o), an aryl (C-6-Cie) and -OH . In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein R ₉ is a COO ^" group and R10 is

OCr In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein Rg is an O ^" group and R10 is

coo-

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein R ₉ is an O ^" group a

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [IV], wherein R ₉ is an COO ^" group and R10 is

OO ^" . In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and Xs are O ^" . In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and Xs are COO ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [V], having a z value of 1 and wherein X ₇ and Xs are O ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one unit of the group of formula [V], having a z value of 0 and wherein X ₇ and Xs are COO ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises at least one unit of a cyclodextrin group of formula [II], at least one unit of an -alkyl(Ci-C5o)-X group wherein the X group is consisting of SO3 ^" , SO ₄ ^" , -NH ^" , PO3 ^2" and COO ^" ; and at least one group of formula [VI]. More preferably, the -alkyl(Ci-C ₅₀ )-X is alkyl(C ₄ )-SO ₃ ^" .

In another preferred embodiment of the invention, the modified layered double hydroxide described before comprises one phytic acid and one unit of a cyclodextrin group of formula [II]. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. Methods and materials similar or equivalent to those described herein can be used in the practice of the present invention. Throughout the description and claims the word "comprise" and its variations are not intended to exclude other technical features, additives, components, or steps. Additional objects, advantages and features of the invention will become apparent to those skilled in the art upon examination of the description or may be learned by practice of the invention. The following examples are provided by way of illustration and are not intended to be limiting of the present invention.

EXAMPLES

EXAMPLES A: SYNTHESIS OF MODIFIED LAYER DOUBLE HYDROXIDES LDHS

Example A-1: Synthesis of organo modified layer double hydroxide LDHs comprising sodium dodecylbenzenesulfonate (SDBS), β-cvclodextrin anion and Taurine (SDBS50-CDBS-T-LDH). The preparation of a modified Mg ₂ AI-LDH comprising sodium dodecylbenzenesulfonate (SDBS) (50%), functional β-cyclodextrin anion (25%) and Taurine (25%) is described in this example.

In a 100 ml round-bottom flask, 4.54 g β-cyclodextrin (β-CD) (0.004mol) was added with stirring to a solution composed of 15 ml water and 3.0 g NaOH. The reaction system was heated to 60 oC, and 5.45 g 1 ,4-butane sultone (BS) (0.04mol) was dropwisely added with vigorous stirring over a period of 10 min. The mixture was kept at the temperature of 70 oC. After cooling to 50oC, allyl glycidyl ether in different amounts, 1 .83 g (0.016mol) or 9.5928 g (0.084mol), was slowly added, and then the mixture was stirred for another 6 h. The resulting solution was neutralized with 1 N hydrochloric acid and dialyzed against 3x1000 ml water to remove salts, 3-allyloxy-1 ,2-propanediol, and hydroxyalkyl sulfonic acids formed as side products. The diasylate was then poured out into 200 ml of ethanol to get functional β-cyclodextrin anion.

A solution of 51.2 g Mg(N0 ₃ ) ₂ .6H ₂ 0 and 37.5 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 300 ml deionized water, a solution containing 28 g NaOH in 300 ml distilled water and a solution comprising 17.42 g sodium dodecylbenzenesulfonate (SDBS) and 50.51 g β-cyclodextrin anions in 300 ml deionized water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the modifers' solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ CO ₃ of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 95%)

The product mixed with 100 ml dionized water. Then, 9 g Taurine reacted with NaOH (1 M) until neutralized solution and add to the above mixture under continuous vigorous stirring. The material was then washed, filtered and dried in vacuum oven at 80°C till the constant weight was achieved.

Example A-2: Synthesis of organo modified layer double hydroxide LDHs comprisinp sodium dodecylbenzenesulfonate (SDBS), β-cyclodextrin anion and Taurine (SDBS65-CDBS-T-LDH).

The preparation of a modified Mg ₂ AI-LDH comprising sodium dodecylbenzenesulfonate (SDBS) (65%), functional β-cyclodextrin anion (17.5%) and Taurine (17.5%) is described in this example. A solution of 51 .2 g Mg(N0 ₃ ) ₂ .6H ₂ 0 and 37.5 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 300 ml deionized water, a solution containing 28 g NaOH in 300 ml distilled water and 22.65 g sodium dodecylbenzenesulfonate (SDBS) and 35.36 g β-cyclodextrin anions in 300 ml deionized water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the modifers' solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ CO ₃ of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 95%) The product mixed with 100 ml dionized water. Then, 6 g Taurine reacted with NaOH (1 M) until neutralized solution and add to the above mixture under continuous vigorous stirring. The material was then washed, filtered and dried in vacuum oven at 80°C till the constant weight was achieved.

Example A-3: Synthesis of organo modified layer double hydroxide LDHs comprising sodium dodecylbenzenesulfonate (SDBS), functional β-cyclodextrin anion and Taurine (SDBS75-CDBS-T-LDH).

The preparation of a modified Mg ₂ AI-LDH comprising sodium dodecylbenzenesulfonate (SDBS) (75%), functional β-cyclodextrin anion (12.5%) and Taurine (12.5%) is described in this example. First of all, a solution of 51 .2 g Mg(NO ₃ ) ₂ .6H ₂ O and 37.5 g AI(NO ₃ ) ₃ .9H ₂ O in 300 ml deionized water, a solution containing 28 g NaOH in 300 ml distilled water and a solution comprising 26.13 g sodium dodecylbenzenesulfonate (SDBS) and 25.25 g functional β-cyclodextrin anions in 300 ml deionized water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the modifers' solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ C0 ₃ of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 95%)

Example A-4: Synthesis of organo modified layer double hydroxide LDHs comprising production of silicon modified phenyl phosphate compound (SiP- LDH). Synthesis of 4,4'-(1 ,3-dipropyl-tetramethyldisiloxane)bis-2-methoxyphenol (SIE): In a three-necked 500 ml round-bottomed flask equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser, eugenol (16.42 g, 0.1 mol) and chloroplatinic acid in isopropyl alcohol (1 .44*10 ^~2 g, Pt 0.8 wt%) were charged. The mixture was heated to 60°C, and 1 ,1 ,3,3- tetramethyldisiloxane(6.72 g, 0.05 mol) was dropped slowly in 3 h. The exothermic reaction occurred at 60-70 °C. When 1 ,1 ,3,3-tetramethyldisiloxane was dropped over, the reaction was carried out for another 1 h. The unreacted reactants were removed using a rotary evaporator under vacuum at 80 . The acquired product was SIE (97 % yield).

Synthesis of silicon modified phenyl phosphate compound: In a three-necked 500 ml round-bottomed flask equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser, a mixture of SIE(23.14 g, 0.05 mol), CuCI (0.1 g, 0.001 mol) and tetrahydrofuran (200 ml) were dropped into phenyl dicholophosphate (21 .10 g, 0.1 mol) in 0 °C. Then the reaction was taken in room temperature for 60 h. The product was filtrated to remove solid residue, and rotovaped to remove solvents (tetrahydrofuran). The acqured products was silicon modified phenyl cholophosphate (91 % yield).

Synthesis of organic LDH: The silicon modified phenyl cholophosphate (31.65 g, 0.15 mol) was added into 100 ml distilled water. The pH value of the mixture was adjusted to 8-12 with 0.1 M NaOH solution (SPC). Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution (with Mg ²⁺ :AI ³⁺ mol ratio equal to 2:1 and a total metal ion concentration of 0.3 M, either metal nitrate salts or metal chloride salts as original source to solution SPC at 50 °C. During the synthesis the pH value was kept at 10 ± 0.2 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ CO3 of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 95%) Example A-5: Synthesis of organo modified layer double hydroxide LDHs comprising 1, 3, 5 - triazine based compound (TR1-LDH).

0.03mol of 4-aminobenzene sulfonic acid was dissolved in H ₂ O (50ml), and then 0.015mol of K ₂ CO3 was added into the solution. Cyanuric chloride (0.01 mol) in 50ml dioxane was slowly added into the solution with stirring at 0- 5°C. After addition the reaction mixture was continuously stirred in a sealed round bottom flask at ambient temperature up to 3h. Subsequently, the reaction mixture was continuously stirred at 80 °C for 3h. After that, the solvent was distilled in vacuum and the 1 , 3, 5 - triazine based compound (TR1 ) was obtained. A solution of 5.12 g Mg(N0 ₃ ) ₂ .6H ₂ 0 and 3.75 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 30 ml deionized water, a solution containing 2.8 g NaOH in 30 ml distilled water and a solution comprising 7 g 1 , 3, 5 - triazine based compound (TR1 ) in 30 ml deionized water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the modifers' solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ CO ₃ of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 97%)

Example A-6: Synthesis of organo modified layer double hydroxide LDHs comprising 1, 3, 5 - triazine based compound (TR2-LDH).

0.03mol of 4-6-aminocaproic acid was dissolved in H2O (50ml), and then 0.015mol of K ₂ CO ₃ was added into the solution. Cyanuric chloride (0.01 mol) in 50ml dioxane was slowly added into the solution with stirring at 0-5°C. After addition the reaction mixture was continuously stirred in a sealed round bottom flask at ambient temperature up to 3h. Subsequently, the reaction mixture was continuously stirred at 80 °C for 3h. After that, the solvent was distilled in vacuum and the 1 , 3, 5 - triazine based compound (TR2) was obtained.

A solution of 5.12 g Mg(NO ₃ ) ₂ .6H ₂ O and 3.75 g AI(NO ₃ ) ₃ .9H ₂ O in 30 ml deionized water, a solution containing 2.8 g NaOH in 30 ml distilled water and a solution comprising 7 g 1 , 3, 5 - triazine based compound (TR2) in 30 ml deionized water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the modifers' solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution or mixed solution of NaOH and Na ₂ C03 of a molar ration equal to 5. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 97%) Example A-7: Synthesis of orpano modified layer double hydroxide LDHs comprising 1, 3, 5 - triazine based compound and functional cyclodextrin anion (TR2-CD-LDH).

The synthesis of 1 , 3, 5 - triazine based compound (TR2) was described in Example A-6 and the synthesis of functional cyclodextrin anion was described in Example A-1 .

0.05 mol triazine based compound (TR2) and 0.05 mol functional cyclodextrin anion were dissolved in the deionized water with stirring in 92 °C for 24 h, aiming to prepare inclusion compounds which were used as modifier for functional LDH.

A solution of 5.12 g Mg(N0 ₃ ) ₂ .6H ₂ 0 and 3.75 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 30 ml deionized water, and a solution containing 2.8 g NaOH in 30 ml distilled water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the inclusion compounds solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 94%)

Example A-8: Synthesis of organo modified layer double hydroxide LDHs comprisinp 1, 3, 5 - triazine based compound and functional cyclodextrin anion (TR1-CD-LDH).

The synthesis of 1 , 3, 5 - triazine based compound (TR1 ) was described in Example A-5 and the synthesis of functional cyclodextrin anion was described in Example A-1 .

0.05 mol triazine based compound (TR1 ) and 0.05 mol functional β-cyclodextrin anion were dissolved in the deionized water with stirring in 90 °C for 18 h, aiming to prepare inclusion compounds which were used as modifier for functional LDH.

A solution of 5.12 g Mg(N0 ₃ ) ₂ .6H ₂ 0 and 3.75 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 30 ml deionized water, and a solution containing 2.8 g NaOH in 30 ml distilled water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Mg ²⁺ and Al ³⁺ ) salt solution to the inclusion compounds solution at 50 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 90%)

Example A-9: Synthesis of organo modified layer double hydroxide LDHs comprisinp silicon modified phenyl phosphate compound (SiP) and functional cyclodextrin anion (SiP-CD-LDH). The synthesis of silicon modified phenyl phosphate compound (SiP) was described in Example A-4 and the synthesis of functional cyclodextrin anion was described in Example A-1 .

0.06 mol silicon modified phenyl phosphate compound (SiP) and 0.06 mol functional cyclodextrin anion were dissolved in the deionized water with stirring in 95 °C for 24 h, aiming to prepare inclusion compounds which were used as modifier for functional LDH. A solution of 7.02 g Zn(N0 ₃ ) ₂ .9H ₂ 0 and 3.75 g AI(N0 ₃ ) ₃ .9H ₂ 0 in 40 ml deionized water, and a solution containing 2.8 g NaOH in 30 ml distilled water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Zn ²⁺ and Al ³⁺ ) salt solution to the inclusion compounds solution at 40 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 93%)

Example A-10: Synthesis of orpano modified layer double hydroxide LDHs comprising sodium dodecylbenzenesulfonate (SDBS), β-cvclodextrin anion and Phytic acid sodium salt hydrate (SDBS-CD-P-LDH).

The synthesis of functional β-cyclodextrin anion was described in Example A-1.

0.02 mol sodium dodecylbenzenesulfonate (SDBS), 0.04 mol Phytic acid sodium salt hydrate and 0.06 functional cyclodextrin anion were dissolved in 200 ml deionized water with stirring in 92 °C for 24 h, aiming to prepare inclusion compounds which were used as modifier for functional LDH.

A solution of 7.02 g Zn(NO ₃ ) ₂ -9H ₂ O and 3.75 g AI(NO ₃ ) ₃ .9H ₂ O in 40 ml deionized water, and a solution containing 2.8 g NaOH in 30 ml distilled water were prepared. Synthesis of organic LDHs was carried out by the slow addition of a mixed metal (Zn ²⁺ and Al ³⁺ ) salt solution to the inclusion compounds solution at 40 °C. During the synthesis the pH value was kept between 9-12 by adding suitable amount of 1 M NaOH solution. After the addition of the mixed metal salt solution, the resulting slurry was continuously stirred at the same temperature for 0.5 h and then was allowed to age in heater at 75 °C for 18 h. The final products were filtered and washed several times with distilled water to get rid of non-reacted surfactant molecules until the pH of the supernatant solution was about 7. The material was then dried in oven at 80 °C till the constant weight was achieved. (Yield over 89%) EXAMPLES B: POLYMERIC COMPOSITIONS Explanations for understanding the results.

The limiting oxygen index (LOI) is the minimum concentration of oxygen (expressed as a percentage) that will support combustion of a polymer. It was measured by passing a mixture of oxygen and nitrogen over a burning specimen, and reducing the oxygen level until a critical level was reached. LOI values for the composites were determined by standardized tests, according to the ASTM D2863 (samples of dimensions 130 χ 6.5 χ 3.2 mm ³ ).

UL 94 is a plastics flammability standard released by Underwriters Laboratories of the USA. The standard classifies plastics according to how they burn in various orientations and thicknesses. From lowest (least flame-retardant) to highest (most flame-retardant), the classifications are: HB: slow burning on a horizontal specimen; burning rate < 76 mm/min for thickness < 3 mm and burning stops before 100 mm

V2 burning stops within 30 seconds on a vertical specimen; drips of flaming particles are allowed.

· V1 : burning stops within 30 seconds on a vertical specimen; drips of particles allowed as long as they are not inflamed.

V0: burning stops within 10 seconds on a vertical specimen; drips of particles allowed as long as they are not inflamed.

5VB: burning stops within 60 seconds on a vertical specimen; no drips allowed; plaque specimens may develop a hole.

5VA: burning stops within 60 seconds on a vertical specimen; no drips allowed; plaque specimens may not develop a hole

Cone Calorimeter Test (CCT): p-HRR: peak Heat Release Rate, THR: Total Heat Release and TSP: Total Smoke Production.

The cone calorimeter test (CCT) is the most significant bench scale instrument to study the fire behavior of small specimen of various materials, following the procedures in ISO 5660 (without the use of the "frame and grid") using an FTT cone calorimeter. Square specimens (100x100^3 mm ³ ) were irradiated at a heat flux of 50 kW/m ² . This method is able to investigate some important parameters in a fire, like heat release rate (HRR), peak of heat release rate (p- HRR), total heat release (THR), total smoke production (TSP), among others.

Tg (Glass transition temperature)

The glass-liquid transition (or glass transition for short) is the reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle state into a molten or rubber-like state. In this invention all Tg have been measured by dynamic mechanical analysis (DMA).

Example B-1: A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl;

26.5 parts of 4-aminophenyl sulfone;

8 parts of the SDBS50-CDBS-T-LDH described in Example A-1 (6 wt% based on the total weight of the cured product)

Curing process:

100 g of Bisphenol A diglycidyl and 8 g of the SDBS65-CDBS-T-LDH described in Example A-1 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 26.5 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 6wt% unmodified LDH based epoxy has been prepared as well.

Table 1 : Properties of the composition described in Example B-1 .

Example B-2:

A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl ; 26.5 parts of 4-aminophenyl sulfone;

8 parts of the SDBS65-CDBS-T-LDH described in Example A-2 (6 wt% based on the total weight of the cured product) Curing process:

100 g of Bisphenol A diglycidyl and 8 g of the SDBS65-CDBS-T-LDH described in Example A-2 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 26.5 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 6wt% unmodified LDH based epoxy has been prepared as well. Table 2: Properties of the composition described in Example B-2.

Example B-3

A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl;

26.5 parts of 4-aminophenyl sulfone;

8 parts of the SDBS75-CDBS-T-LDH described in Example A-3 (6 wt% based on the total weight of the cured product) Curing process:

100 g of Bisphenol A diglycidyl and 8 g of the SDBS75-CDBS-T-LDH described in Example A-3 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 26.5 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 6wt% unmodified LDH based epoxy has been prepared as well.

Table 3: Properties of the composition described in Example B-3.

Example B-4

All materials including PLA 225g, flame retardant 69g (containing ammonium polyphosphate (APP), pentaerythritol (PER) and melamine cyanurate (MC) by controlling the weight ratio was 2:2:1 ) and organomodified LDH 6g (described in Example A-3) were dried under vacuum at 70 °C for 24 h before used. All the samples were compounded on a corotating twin-screw microextruder. The conditions used for melt-compounding steps were 190 °C with 200 rpm screw speed for 10 min. As a comparative study, an intumescent flame retarded PLA composite has been prepared by the same way. Table 4: Properties of the composition described in Example B-4.

Example B-5

The rubber (maleic anhydride grafted ethylene-propylene-diene terpolymer (mEPDM)) compounds were prepared by two-roll mixing mill (Polymix 1 10L Germany) with the friction ratio 1 :1 .2 rotating at 40°C using 20 min compounding cycle. All the weights were taken in parts per hundred of rubber and the recipe of the mEPDM compounds is given as follows:

Formulation of the mEPDM compound (in weight parts per hundred of rubber (phr))

a described in Example A-3 ^b an intumescent flame retardant (FR) comprised of pentaerythritol (PER), ammonium polyphosphate (APP) and methyl cvanoacetate (MCA).

c Dicumyl peroxide (DCP) was used as a crosslinking agent Firstly, requisite amounts of LDH and FR were incorporated in the rubber. After addition of those additives the dicumyl peroxide was added for the crosslinking of the rubber matrix. After mixing the rubber according to the above described procedure the compounded sample was obtained, and was subjected to the optimum curing time. From torque-time curve the curing time was calculated to that point at which the rheometric torque reached 90 % value of its ultimate torque. The rubber samples were then cured until their optimum curing time (t90) by a hot press (FORTUNE Holland, Modell TP 400) at 160°C, cooled to room temperature and then kept for 24 h before doing any further test. Table 5: Properties of the composition described in Example B-5.

Example B-6

A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl ;

26.5 parts of 4-aminophenyl sulfone;

14 parts of the SDBS65-CDBS-T-LDH described in Example A-2 (10 wt% based on the total weight of the cured product) Curing process:

100 g of Bisphenol A diglycidyl and 14 g of the SDBS65-CDBS-T-LDH described in Example A-2 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 26.5 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 10wt% unmodified LDH based epoxy has been prepared as well.

Table 6: Properties of the composition described in Example B-6.

Example B-7 A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl ;

26.5 parts of 4-aminophenyl sulfone;

14 parts of the SDBS75-CDBS-T-LDH described in Example A-3 (10 wt% based on the total weight of the cured product)

Curing process:

100 g of Bisphenol A diglycidyl and 14 g of the SDBS75-CDBS-T-LDH described in Example A-3 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 26.5 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 10wt% unmodified LDH based epoxy has been prepared as well. Table 7: Properties of the composition described in Example B-7.

Example B-8

A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl ;

35 parts of 4-aminophenyl sulfone;

11 .7 parts of the SiP-LDH described in Example A-4 (8 wt% based on the total weight of the cured product) Curing process:

100 g of Bisphenol A diglycidyl and 11 .7 g of the SiP-LDH described in Example A-4 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 35 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 8wt% unmodified LDH based epoxy has been prepared as well. Table 8: Properties of the composition described in Example B-8. LOI UL94 p-HRR THR TSP Tg

Sample

(%) (3.2±0.3) (kW/m ² ) (MJ/m ² ) (m ² ) (°C)

SiP-LDH-

25.8 V-0 409 20.9 21 210 Epoxy

Unmodified

25.4 No rating 570 23.8 23 21 1 LDH-Epoxy

Example B-9

A curable polymeric composition was made by mixing:

100 parts by weight of Bisphenol A diglycidyl ;

35 parts of 4-aminophenyl sulfone;

11 .7 parts of the SiP-CD-LDH described in Example A-9 (8 wt% based on the total weight of the cured product) Curing process:

100 g of Bisphenol A diglycidyl and 11 .7 g of the SiP-CD-LDH described in Example A-9 was mixed for 0.5 h followed by dissolving in 50 ml of Acetone and ultrasonication for 25 min at 65°C. Then, the mixture was heated to 85 °C for 0.5 h and increased the temperature to 120 °C for 0.5 h in order to remove the solvent. 35 g of 4-aminophenyl sulfone, was added as a hardener at 120 °C and mix until clear solution obtain. The mixture was cured at 150°C for 1 hour, 180°C for 2 hours and 200°C for 2 hours respectively. In comparison, 8wt% unmodified LDH based epoxy has been prepared as well. Table 9: Properties of the composition described in Example B-9.

LOI UL94 p-HRR THR TSP Tg

Sample

(%) (3.2±0.3) (kW/m ² ) (MJ/m ² ) (m ² ) (°C)

SiP-CD-LDH-

25.9 V-0 403 20.7 21 206 Epoxy Unmodified

25.4 No rating 570 23.8 23 211

LDH-Epoxy

Example B-10

The rubber (maleic anhydride grafted ethylene-propylene-diene terpolymer (mEPDM)) compounds were prepared by two-roll mixing mill (Polymix 1 10L Germany) with the friction ratio 1 :1 .2 rotating at 40°C using 20 min compounding cycle. All the weights were taken in parts per hundred of rubber and the recipe of the mEPDM compounds is given as follows: Formulation of the mEPDM compound (in weight parts per hundred of rubber (phr))

b an intumescent flame retardant (FR) comprised of pentaerythritol (PER), ammonium polyphosphate (APP) and methyl cyanoacetate (MCA).

c Dicumyl peroxide (DCP) was used as a crosslinking agent

Firstly, requisite amounts of LDH and FR were incorporated in the rubber. After addition of those additives the dicumyl peroxide was added for the crosslinking of the rubber matrix. After mixing the rubber according to the above described procedure the compounded sample was obtained, and was subjected to the optimum curing time. From torque-time curve the curing time was calculated to that point at which the rheometric torque reached 90 % value of its ultimate torque. The rubber samples were then cured until their optimum curing time (t90) by a hot press (FORTUNE Holland, Modell TP 400) at 160°C, cooled to room temperature and then kept for 24 h before doing any further test. Table 10: Properties of the composition described in Example B-10.

p-HRR Time to Fire growth Residue Tensile Strength

Sample

(kW/m ² ) p-HRR rate (%) (MPa)

mEPDM 631 150 4.20 6 3.20 mEPDM-FR 451 215 2.10 17 4.21 mEPDM-FR

SDBS-CD-P- 352 241 1 .45 27 5.08

LDH