Two-component thermally conductive composition of silyl polymer

Abstract

The invention relates to a two-component thermally conductive composition comprising: a composition (A) comprising: a silyl polymer, and a composition (B) comprising: at least 1% by weight of a filler (C) relative to the total weight of the composition (B), the filler (C) providing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler, and the composition (A) and / or the composition (B) further comprising: a rheology agent (r1) chosen from amide waxes and / or a rheology agent (r2) comprising: from 1% to 40% by weight of a bisurea (a) obtained by reaction of an aliphatic primary amine with a diisocyanate having a molar mass of less than 500 g / mol, relative to the total weight of the rheology agent (r2), and from 60% to 99% by weight of a specific plasticizer (b), relative to the total weight of the rheology agent (r2), said rheology agent (r2) being in the form of a suspension of solid particles of bisurea (a) in a continuous phase of plasticizer (b). The invention also relates to the use of a filler (C) having a specific moisture content, for the crosslinking, without addition of free water, of a two-component composition, the two-component composition comprising a composition (A) comprising a silyl polymer, and a composition (B) comprising said filler (C).

Description

[0001] Two-component thermally conductive silylated polymer composition

[0002] Field of invention

[0003] The present invention relates to a thermally conductive two-component composition of silylated polymer, as well as its use in particular for improving the service life of a battery. The present invention also relates to the use of a filler (C) having a specific moisture content, for crosslinking without adding free water of a two-component composition of silylated polymer.

[0004] Technical background

[0005] There are various polymer-based compositions on the market that can be used in many areas, including as adhesives and / or sealants. Adhesives and sealants are used to assemble (or join or bond) two substrates that can be chosen from a wide variety of materials.

[0006] For example, polymer-based compositions can be used as adhesives and / or sealants in building construction, shipbuilding, or the transportation sector (e.g., road, maritime, rail or aerospace).

[0007] Compositions based on alkoxysilane-terminated polymers (also known as silylated polymers) have the advantage of being isocyanate-free. These compositions therefore constitute a preferred alternative from a toxicological point of view to compositions based on isocyanate-terminated polyurethanes, which are very often found on the adhesive market.

[0008] The crosslinking reaction of these silylated polymer-based compositions occurs, in the presence of moisture, by hydrolysis of the alkoxysilane groups carried by the polymer, then their condensation to form a siloxane bond (-Si- O— Si— ) which unites the polymer chains into a solid three-dimensional network.

[0009] Some applications, particularly assemblies for battery manufacturing, require the polymer composition to have specific properties, particularly in terms of thermal conductivity. Indeed, since recharging a battery is generally accompanied by an increase in temperature, it is important to limit this increase as much as possible, which is likely to degrade certain electronic circuits or even reduce the battery's lifespan. It is therefore important that the silylated polymer composition has sufficient thermal conductivity to overcome these problems. However, closed assemblies such as batteries do not allow enough air (and therefore moisture) to pass through for the crosslinking reaction of the silylated polymer to take place.

[0010] It is possible to use as an adhesive a two-component composition comprising on the one hand the silylated polymer to be crosslinked, and on the other hand water. The two components of the adhesive are often packaged separately in the two compartments of a dual cartridge. The distribution of the adhesive is then carried out at the time of application on the substrates to be assembled by extrusion of the two components, for example using a dual cartridge gun, and following their homogeneous mixing obtained, for example, by attaching a static mixer to the dual cartridge. The reaction of the component comprising the silylated polymer with the component comprising water allows the crosslinking of the silylated polymer.

[0011] However, water is hydrophilic while the silylated polymer is hydrophobic. Thus, there is a problem of processability when mixing the components because it is difficult to mix the component comprising water with the component comprising the silylated polymer, the water generally being deposited on the mixer blades.

[0012] There is therefore a need to provide a two-component silylated polymer composition which has both good thermal conductivity and good processability.

[0013] In addition, there is a need to provide a two-component thermally conductive silylated polymer composition that crosslinks rapidly. This property can be assessed by measuring the open time of the composition: the shorter it is, the faster the composition crosslinks.

[0014] Furthermore, there is a need to provide a two-component thermally conductive silylated polymer composition that can be easily applied with a manual dual cartridge while limiting the risk of dripping, particularly in a non-horizontal position.

[0015] Summary of the invention

[0016] The present invention relates to a two-component thermally conductive composition comprising:

[0017] - a composition (A) comprising: o a silylated polymer, and o a rheology agent (r1) chosen from amide waxes and / or o a rheology agent (r2) comprising: ■ from 1% to 40% by weight of a bis-urea (a) obtained by reaction of a primary aliphatic amine with a diisocyanate of molar mass less than 500 g / mol, relative to the total weight of the rheology agent (r2), and

[0018] ■ from 60% to 99% by weight of a plasticizer (b) chosen from alkylphthalates, pentaerythritol tetravalerate, alkylsulfonic acid esters of phenol, diisononyl-1,2-cyclohexane dicarboxylate, 3,3'-[methylenebis(oxymethylene)]bis[heptane], dioctyl carbonate and mixtures thereof, relative to the total weight of the rheology agent (r2), said rheology agent (r2) being in the form of a suspension of solid particles of bis-urea (a) in a continuous phase of plasticizer (b), and

[0019] - a composition (B) comprising: o at least 1% by weight of a filler (C) relative to the total weight of the composition (B), the filler (C) providing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler.

[0020] The present invention also relates to the use of the two-component thermally conductive composition according to the invention as an adhesive and / or sealant.

[0021] Furthermore, the present invention also relates to the use of the two-component thermally conductive composition according to the invention as an adhesive in the field of building construction, in the field of manufacturing means of transport, preferably in the automotive, railway and aerospace industries, and in the field of shipbuilding.

[0022] The present invention also relates to the use of the thermally conductive two-component composition according to the invention for improving the lifespan of a battery, preferably a rechargeable battery.

[0023] Furthermore, the invention relates to the use of a filler (C) having a moisture content of between 0.05% and 5% by weight, relative to the total weight of the filler (C), for crosslinking without adding free water a two-component composition, the two-component composition comprising a composition (A) comprising a silylated polymer, and a composition (B) comprising said filler (C). The present invention also relates to an article, in particular a battery, comprising the thermally conductive two-component composition according to the invention.

[0024] Finally, the present invention relates to a method of assembling two substrates by gluing, comprising:

[0025] - coating on at least one of the two substrates to be assembled the thermally conductive two-component composition according to the invention, then

[0026] - the effective contact of the two substrates.

[0027] Surprisingly, it has been found that the incorporation of a filler (C) into the composition (B), providing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), not only makes it possible to improve the mixing of the composition (A) with the composition (B), and thus to limit the processability problems (in particular to limit the deposition of water on the blades of the mixer), but also leads to the rapid crosslinking of the silylated polymer after contact with the composition (A), without it being necessary to add (free) water to the composition (B). In addition, the thermally conductive two-component composition according to the invention can not only be easily applied with a manual two-cartridge (without the need for a pneumatic gun), but also limits the risk of dripping, in particular in a non-horizontal position.

[0028] Description of the invention

[0029] Thus, the invention relates to a two-component thermally conductive composition comprising:

[0030] - a composition (A) comprising: o a silylated polymer, and

[0031] - a composition (B) comprising: o at least 1% by weight of a filler (C) relative to the total weight of the composition (B), the filler (C) providing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler, and the composition (A) and / or the composition (B), preferably the composition (A), further comprising: o a rheology agent (r1) chosen from amide waxes and / or o a rheology agent (r2) comprising:

[0032] ■ from 1% to 40% by weight of a bis-urea (a) obtained by reaction of a primary aliphatic amine with a diisocyanate of molar mass less than 500 g / mol, relative to the total weight of the rheology agent (r2), and

[0033] ■ from 60% to 99% by weight of a plasticizer (b) chosen from alkylphthalates, pentaerythritol tetravalerate, alkylsulfonic acid and phenol esters, diisononyl-1,2-cyclohexane dicarboxylate, 3,3'-[methylenebis(oxymethylene)]bis[heptane], dioctyl carbonate and mixtures thereof, relative to the total weight of the rheology agent (r2), said rheology agent (r2) being in the form of a suspension of solid particles of bis-urea (a) in a continuous phase of plasticizer (b).

[0034] Silylated polymer

[0035] By "silylated polymer" is meant a polymer comprising at least one alkoxysilane group. Preferably, the silylated polymer comprises at least one alkoxysilane group at the end of the polymer.

[0036] The silylated polymer is generally in the form of a more or less viscous liquid. Advantageously, the silylated polymer has a viscosity at 23°C ranging from 0.5 to 200 Pa.s, preferably from 5 to 120 Pa.s, more preferably from 15 to 80 Pa.s, even more preferably from 30 to 60 Pa.s.

[0037] The viscosity of the silylated polymer can for example be measured using a Brookfield type method at 23°C and 50% relative humidity (S28 needle).

[0038] Within the scope of the invention, the ranges of values ​​are understood to include the limits. For example, the range “between 0% and 25%” includes in particular the values ​​0% and 25%.

[0039] Advantageously, the silylated polymer comprises at least one, preferably at least two, alkoxysilane groups of formula (I): in which:

[0040] - R 4represents a linear or branched alkyl radical comprising from 1 to 4 carbon atoms, and when p is equal to 2, the radicals R 4 are the same or different, - R 5 represents a linear or branched alkyl radical comprising from 1 to 4 carbon atoms, and when p is equal to 0 or 1, the radicals R 5 are identical or different, two OR groups 5 which can be engaged in the same cycle, and

[0041] - p is an integer equal to 0, 1 or 2, preferably equal to 0 or 1.

[0042] Preferably, the alkoxysilane groups of the silylated polymer are of formula (I) with:

[0043] - R 4 and R 5 each represent a methyl radical, and

[0044] - p is equal to 0 or 1.

[0045] Advantageously, the silylated polymer has a number-average molecular mass of between 500 g / mol and 70,000 g / mol, preferably between 1,000 g / mol and 60,000 g / mol, more preferably between 2,000 g / mol and 50,000 g / mol.

[0046] The molar mass of polymers can be measured by methods well known to those skilled in the art, for example by NMR or by size exclusion chromatography using polystyrene-type standards.

[0047] Advantageously, the silylated polymer is of formula (II), (III) or (IV): av) in which:

[0048] - R 4 , R 5 and p have the same meaning as in formula (I) described above,

[0049] - P represents a saturated or unsaturated polymeric radical, with a linear or branched open chain, or comprising one or more optionally aromatic cycles, optionally comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur and / or silicon, preferably oxygen and / or nitrogen,

[0050] - R 1 represents a divalent hydrocarbon radical comprising from 5 to 15 carbon atoms, saturated or unsaturated, with a linear or branched open chain, or comprising one or more optionally aromatic cycles, R 3 represents a linear or branched divalent alkylene radical comprising from 1 to 6 carbon atoms, preferably from 1 to 3 carbon atoms,

[0051] - X represents a divalent radical chosen from -NH-, -NR 7 - or -S-,

[0052] - R 7 represents a linear or branched alkyl radical comprising from 1 to 20 carbon atoms and which may also comprise one or more heteroatoms,

[0053] - f is an integer ranging from 1 to 6, advantageously from 2 to 5, preferably from 2 to 4, even more preferably from 2 to 3.

[0054] Advantageously, the silylated polymer is of formula (II), (III) or (IV) with P representing a polymeric radical chosen from polyethers, polycarbonates, polyesters, polyolefins, polyacrylates, polyether polyurethanes, polyester polyurethanes, polyolefin polyurethanes, polyacrylate polyurethanes, polycarbonate polyurethanes, polyether / polyester block polyurethanes, preferably chosen from polyethers, polyurethanes and their mixtures, more preferably from polyethers.

[0055] Preferably, the silylated polymer is of formula (IT), (II”), (III') or (IV'): in which:

[0056] R 1 , R 3 , R 4 , R 5 , X, R 7 and p have the same meaning as in formulas (II), (III) and (IV),

[0057] - R 2 represents a saturated or unsaturated, linear or branched divalent hydrocarbon radical optionally comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur, silicon, - n is an integer, preferably n is such that the number-average molecular mass of the silylated polymer is between 500 g / mol and 70,000 g / mol, more preferably between 1,000 g / mol and 60,000 g / mol, even more preferably between 2,000 g / mol and 50,000 g / mol.

[0058] In the silylated polymers of formulas (IT), (II”), (III') or (IV') defined above, when the radical R 2 comprises one or more heteroatoms, said heteroatom(s) are not present at the end of the chain. In other words, the free valences of the divalent radical R 2 linked to the neighboring oxygen atoms of the silylated polymer, each come from a carbon atom. Thus, the main chain of the radical R 2is terminated by a carbon atom at each of the two ends, said carbon atom then having a free valence.

[0059] According to one embodiment, the silylated polymers are obtained from polyols chosen from polyether polyols, polyester polyols, polycarbonate polyols, polyacrylate polyols, polysiloxane polyols, polyolefin polyols and mixtures thereof, preferably from diols chosen from polyether diols, polyester diols, polycarbonate diols, polyacrylate diols, polysiloxane diols, polyolefin diols and mixtures thereof, more preferably from polyether diols. In the case of the polymers of formulas (IT), (II”), (III') or (IV') described above, such diols may be represented by the formula HO-R 2 - OH or H-[O- R 2 ] n -OH, where R 2 has the same meaning as in formulas (IT), (II”), (III') or (IV').

[0060] According to one embodiment, when the silylated polymer is of formula (II') or (IV'), the radical R 2 can be chosen from the following divalent radicals whose formulas below show the two free valencies:

[0061] - derived from a polypropylene glycol:

[0062] - derived from a polyester diol - derivative of a polybutadiene diol:

[0063] - derivative of a polyacrylate diol:

[0064] - derived from a polysiloxane diol: in which:

[0065] - q represents an integer such as the molar mass in number of the radical R 2 ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, more preferably from 500 g / mol to 12600 g / mol,

[0066] - r and s represent zero or a non-zero integer such that the number-average molar mass of the radical R 2ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, more preferably from 500 g / mol to 12600 g / mol, it being understood that the sum r+s is different from zero,

[0067] - Q 1 represents a linear or branched, saturated or unsaturated, aromatic or aliphatic divalent alkylene radical, preferably having from 1 to 18 carbon atoms, more preferably from 1 to 8 carbon atoms,

[0068] - Q 2 represents a linear or branched divalent alkylene radical preferably having from 2 to 36 carbon atoms, more preferably from 1 to 8 carbon atoms,

[0069] - Q 3 , Q 4 , Q 5 , Q 6 , Q 7 and Q 8, represent, independently of one another, a hydrogen atom or an alkyl, alkenyl or aromatic radical, preferably having from 1 to 12 carbon atoms, preferably from 2 to 12 carbon atoms, more preferably from 2 to 8 carbon atoms.

[0070] According to one embodiment, R 1 is chosen from the following divalent radicals whose formulas below show the two free valencies: a) the divalent radical derived from isophorone diisocyanate ( I PDI): b) the divalent radical derived from dicyclohexylmethane diisocyanate (H12MDI): c) divalent radicals derived from the 2,4- and 2,6- isomers of toluene diisocyanate (TDI): d) divalent radicals derived from the 4,4' and 2,4'- isomers of diphenylmethane diisocyanate (MDI): e) the divalent radical derived from hexamethylene diisocyanate (HDI): -(CH2)6- f) the divalent radical derived from m-xylylene diisocyanate (m-XDI):

[0071] According to a preferred embodiment, the silylated polymer is of formula (II”) (preferably with R 3 representing a linear or branched divalent alkylene radical comprising 3 carbon atoms) or (III'), preferably (HT), and the radical R 2 preferably represents a linear or branched divalent alkylene radical comprising from 2 to 4 carbon atoms, more preferably a linear or branched divalent alkylene radical comprising 3 carbon atoms, even more preferably an isopropylene radical (of formula -CH2-CH(CH3)-).

[0072] According to a particularly preferred embodiment, the silylated polymer is a polymer of formula (III') in which:

[0073] - R 2 represents an isopropylene radical,

[0074] - R 5 represents a methyl radical, and

[0075] - p is equal to 0.

[0076] The polymers of formula (II), (II') or (II”) can be obtained according to a process described for example in documents EP 2336208 and WO 2009 / 106699. Among the polymers corresponding to formula (II), mention may be made of:

[0077] - GENIOSIL® STP-E10 (available from WACKER-CHEMIE): polyether of formula (II”) comprising two groups of formula (I) of the dimethoxy type (p equal to 1 and R 4 and R 5 represent a methyl group) having a number-average molar mass of 8889 g / mol where R 3 represents a methyl group;

[0078] - GENIOSIL® STP-E30 (available from WACKER-CHEMIE): polyether of formula (II”) comprising two groups of formula (I) of the dimethoxy type (p equal to 1 and R 4 and R 5 represent a methyl group) having a number-average molar mass of 14493 g / mol where R 3 represents a methyl group;

[0079] - DESMOSEAL® S XP 2636 (available from BAYER): polyurethane comprising two groups of formula (I) of the trimethoxy type (p equal to 0 and R 5 represents a methyl group) having a number-average molar mass of 15038 g / mol where R 3 represents an n-propylene group.

[0080] The polymers of formula (III) or (III') can be obtained by hydrosilylation of polyether diallyl ether according to a process described for example in document EP 1829928. Among the polymers corresponding to formula (III), mention may be made of:

[0081] - the MS SAX® 350 polymer (available from KANEKA) corresponding to a polyether comprising two groups of formula (I) of the dimethoxy type (p equal to 1 and R 4 and R 5 represent a methyl group) having a number-average molar mass ranging from 14000 to 16000 g / mol;

[0082] - the MS SAX® 260 polymer (available from KANEKA) corresponding to a polyether comprising two groups of formula (I) of dimethoxy type (p equal to 1, R 4 and R 5 represent a methyl group) having a number-average molar mass of 16000 to 18000 g / mol where R 3 represents an ethyl group;

[0083] - the MS S303H polymer (available from KANEKA) corresponding to a polyether comprising two groups of formula (I) of dimethoxy type (p is equal to 1 and R 4 represents a methyl group) having a number-average molar mass of 21000 to 23000 g / mol;

[0084] - the MS SAX® 520 polymer (available from KANEKA) corresponding to a polyether comprising groups of formula (I) of the trimethoxy type (p equal to 0 and R 5 represents a methyl group) having a number-average molar mass ranging from 29000 to 31000 g / mol.

[0085] The polymers of formula (IV) or (IV') may for example be obtained by reaction of polyol(s) with one or more diisocyanate(s) followed by a reaction with aminosilanes or mercaptosilanes. A process for preparing polymers of formula (IV) or (IV') is described for example in document EP 2583988. A person skilled in the art will be able to adapt the manufacturing process described in this document in the case of the use of different types of polyols. Among the polymers corresponding to formula (IV), mention may be made of:

[0086] SPUR+® 1050MM (available from MOMENTIVE): polyurethane comprising two groups of formula (I) of the trimethoxy type (p equal to 0 and R 5 represents a methyl group) having a number-average molar mass of 16393 g / mol where R 3 represents an n-propyl group;

[0087] SPUR+® Y-19116 (available from MOMENTIVE): polyurethane comprising two groups of formula (I) of the trimethoxy type (p equal to 0 and R 5 represents a methyl group) having a number-average molar mass ranging from 15000 to 17000 g / mol g / mol where R 3 represents an n-propyl group.

[0088] The content of silylated polymer in composition (A) may range from 3% to 40% by weight relative to the total weight of composition (A), preferably from 5% to 35% by weight, more preferably from 10% to 30% by weight, even more preferably from 14% to 28% by weight, in particular from 17% to 22% by weight.

[0089] Rheoloaie Aaent

[0090] The total content of rheology agent in composition (A) may range from 0.2% to 15% by weight relative to the total weight of composition (A), preferably from 1% to 10% by weight, more preferably from 1% to 5% by weight. The total content of rheology agent in composition (B) may range from 0.2% to 15% by weight relative to the total weight of composition (B), preferably from 1% to 10% by weight, more preferably from 1% to 5% by weight.

[0091] Preferably, composition (A) and / or composition (B) comprises a rheology agent (r2). In particular, the rheology agent (r2) is the only rheology agent in composition (A) and / or composition (B).

[0092] Preferably, the composition (A) comprises a rheology agent (r2). In particular, the rheology agent (r2) is the only rheology agent in the composition (A).

[0093] Advantageously, composition (A) only comprises a rheology agent, preferably a rheology agent (r2). In particular, the rheology agent (r2) is the only rheology agent in composition (A).

[0094] Rheology agent (r1)

[0095] By "amide waxes" is meant waxes comprising one or more compounds having at least one amide group. In particular, amide waxes can be obtained from fatty acid(s) (e.g. ricinoleic acid) and (di)amine(s).

[0096] The amide waxes are preferably micronized, that is to say they have an average particle size of less than 1 mm. Advantageously, the amide waxes have an average particle size of less than 500 pm, preferably less than 100 pm, more preferably less than 10 pm.

[0097] The average particle size corresponds advantageously to the d50 particle size, i.e. the maximum size of 50% of the smallest particles by volume, and can be measured with a particle size analyzer, in particular by laser diffraction on a MALVERN type device (for example according to standard NF ISO 13320).

[0098] Unless otherwise indicated, the standards referred to throughout the application are those in effect on the date the application was filed.

[0099] Amide wax rheology agents are generally heat activatable, i.e. a temperature above room temperature (23°C) may be necessary to activate it (in particular, activate its rheological properties) during the preparation of the composition according to the invention.

[0100] The activation temperature depends on the rheology agent. Preferably, the activation temperature of the rheology agent (r1) is less than 80°C, more preferably less than 65°C, even more preferably less than 55°C.

[0101] Examples of commercial amide waxes are CRAYVALLAC® SLX or CRAYVALLAC® SLT marketed by Arkema, or THIXATROL® AS8053 or THIXATROL® MAX (EC No.: 432-430-3) which are available from ELEMENTIS.

[0102] Rheology agent (r2)

[0103] Advantageously, the rheology agent (r2) is such that the bis-urea (a) is obtained by reaction of an n-alkylamine (a1) comprising from 1 to 22 carbon atoms, preferably n-butylamine, with a diisocyanate (a2) of formula (V):

[0104] NCO-R 6 -NCO (V) in which R 6is chosen from one of the following divalent radicals whose formulas below show the 2 free valences:

[0105] - i) the divalent radical derived from isophorone:

[0106] - ii) the divalent radical 4,4'-methylene-bis(cyclohexyl):

[0107] - iii) the divalent radical derived from 2,4-toluene diisocyanate (or 2,4-TDI) or 2,6-toluene diisocyanate (or 2,6-TDI) of respective formulae:

[0108] - iv) the divalent radical derived from 4,2'-diphenylmethylene diisocyanate (or 4,2'-MDI) or 4,4'-diphenylmethylene diisocyanate (or 4,4'-MDI), of respective formulae:

[0109] - v) the hexamethylene radical: -(CH2)6-,

[0110] - vi) the m-xylylene radical:

[0111] , And

[0112] - vii) the hexahydro-m-xylylene radical:

[0113] Preferably, the diisocyanate (a2) is of formula (V) in which R 6 is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, preferably 4,4'-MDI.

[0114] According to a preferred embodiment, the bis-urea (a) is obtained by reaction of n-butylamine with a diisocyanate (a2) of formula (V) in which R 6 is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, preferably 4,4'-MDI.

[0115] As indicated above, the plasticizer (b) is chosen from alkylphthalates, pentaerythritol tetravalerate, alkylsulfonic acid and phenol esters, diisononyl-1,2-cyclohexane dicarboxylate, 3,3'-

[0116] [methylenebis(oxymethylene)]bis[heptane], dioctyl carbonate and mixtures thereof.

[0117] The alkyl phthalates are preferably formed by the group consisting of diisodecyl phthalate (DIDP), di(2-propylheptyl) phthalate and mixtures thereof.

[0118] As regards pentaerythritol tetravalerate, we can cite the product marketed under the brand name Pevalen® by the company Perstorp.

[0119] As regards an ester of alkylsulfonic acid and phenol, we can cite the product Mesamoll®, marketed by the company Lanxess.

[0120] For diisononyl-1,2-cyclohexane dicarboxylate, we can mention the product marketed under the name Hexamoll Dinch® by BASF. 3,3'-[methylenebis(oxymethylene)]bis[heptane] can be identified by its CAS number: 22174-70-5 and is also known under the trade name 2-ethylhexylal, available from LAMBIOTTE.

[0121] Finally, dioctyl carbonate (EC No.: 434-850-2) is available from BASF.

[0122] Advantageously, the rheology agent (r2) is such that the plasticizer (b) is chosen from alkylphthalates, preferably the plasticizer (b) is chosen from diisodecyl phthalate, di(2-propylheptyl) phthalate and their mixtures, more preferably the plasticizer (b) is diisodecyl phthalate.

[0123] According to a preferred embodiment, the rheology agent (r2) consists of:

[0124] - from 1% to 40% by weight of a bis-urea (a) obtained by reaction of a primary aliphatic amine with a diisocyanate of molar mass less than 500 g / mol, relative to the total weight of the rheology agent (r2), and

[0125] - from 60% to 99% by weight of a plasticizer (b) chosen from alkylphthalates, pentaerythritol tetravalerate, alkylsulfonic acid esters of phenol, diisononyl-1,2-cyclohexane dicarboxylate, 3,3'-[methylenebis(oxymethylene)]bis[heptane], dioctyl carbonate and mixtures thereof, relative to the total weight of the rheology agent (r2), said rheology agent (r2) being in the form of a suspension of solid particles of bis-urea (a) in a continuous phase of plasticizer (b), and the bis-urea (a) and the plasticizer (b) being as described above, including the embodiments.

[0126] Advantageously, the rheology agent (r2) comprises, and preferably consists of, from 5 to 30% by weight of the bis-urea (a) and from 70 to 95% by weight of the plasticizer (b), the percentages being relative to the total weight of said rheology agent (r2).

[0127] The bis-urea (a) and the plasticizer (b) are as described above, including the embodiments.

[0128] The rheology agent (r2) used in the two-component thermally conductive composition according to the invention can be prepared according to the process described below.

[0129] The reaction of the primary aliphatic amine with the diisocyanate is highly exothermic. To prevent the large amount of heat formed by the reaction from causing the decomposition of the bis-urea formed, the primary aliphatic amine and the diisocyanate are each dissolved in the plasticizer (b), prior to their reaction, said plasticizer (b) thus serving to remove the heat formed by the reaction. The two solutions in the plasticizer (b) of the primary aliphatic amine and the diisocyanate are advantageously each introduced into a reactor by injectors, under a pressure of 40 to 200 bar, preferably 80 to 120 bar, the two solutions thus being brought into contact in the state of sprayed liquid. The quantities of reactants preferably correspond to a ratio (number of moles of primary aliphatic amine) / (number of moles of diisocyanate) of approximately 2.Bis-urea is produced by the reaction in the form of solid particles dispersed in a continuous phase of plasticizer b), the Brookfield viscosity of the corresponding suspension, measured at a temperature of 23 °C, generally being between 1 and 50 Pa.s, preferably between 10 and 25 Pa.s.

[0130] By "about X", we mean more or less 10% of the value of X.

[0131] The filler (C) of the composition (B) comprises residual moisture allowing the alkoxysilyl groups of the silylated polymer to be hydrolyzed, which advantageously leads to crosslinking of the silylated polymer, without the need to add water to the composition (B).

[0132] The charge (C) is different from the thermally conductive charge.

[0133] The incorporation of this filler (C) into composition (B) advantageously makes it possible to obtain a more homogeneous thermally conductive two-component composition. Indeed, composition (A) being hydrophobic, in particular due to the presence of the silylated polymer, its mixing with composition (B) is therefore facilitated when the water is provided by filler (C).

[0134] Advantageously, the filler (C) provides at least 0.005% by weight of moisture relative to the total weight of the composition (B), preferably at least 0.010% by weight, more preferably at least 0.015% by weight.

[0135] Advantageously, the filler (C) provides between 0.0025% and 1% by weight of moisture relative to the total weight of the composition (B), preferably between 0.005% and 0.8% by weight, more preferably between 0.010% and 0.5% by weight, even more preferably between 0.015% and 0.2% by weight.

[0136] The moisture provided by the filler (C) can be determined by taking into account the filler (C) content of the composition (B), as well as the moisture content of said filler (C). For example, if the composition (B) comprises 5% by weight of a filler (C), relative to the total weight of the composition (B), and the filler (C) comprises 0.5% by weight of moisture relative to the total weight of the filler (C), then the filler (C) provides (5*0.5) / 100= 0.025% by weight of moisture relative to the total weight of the composition (B). Advantageously, the moisture content of the filler (C) is between 0.05% and 5% by weight relative to the total weight of the filler (C), preferably between 0.1% and 3% by weight, more preferably between 0.10% and 2% by weight.

[0137] A person skilled in the art knows how to determine the moisture content of a load (C). The moisture content of the load (C) can be determined according to the Karl Fisher method by determining the equivalence point electrometrically. For example, the moisture content can be determined by following the protocol described in Example 1 below.

[0138] The average particle size of the filler (C) may range from 10 nm to 400 pm, preferably from 20 nm to 100 pm, more preferably from 30 nm to 50 pm.

[0139] The average particle size corresponds advantageously to the d50 particle size, i.e. the maximum size of 50% of the smallest particles by volume, and can be measured with a particle size analyzer, in particular by laser diffraction on a MALVERN type device (for example according to standard NF ISO 13320).

[0140] Advantageously, the filler (C) is chosen from clays, talc, kaolins, gypsum, carbonate fillers, zeolites, expandable graphite and their mixtures.

[0141] Preferably, the filler (C) is chosen from carbonate fillers, zeolites, expandable graphite and their mixtures, more preferably from carbonate fillers, zeolites and their mixtures.

[0142] Advantageously, the carbonated fillers are formed by the group consisting of alkali or alkaline earth metal carbonates and their mixtures, preferably the carbonated fillers are calcium carbonate or chalk, more preferably calcium carbonate, in particular precipitated calcium carbonate coated with fatty acids.

[0143] When calcium carbonate is coated with fatty acids, this makes the calcium carbonate particles completely or partially hydrophobic. In addition, the fatty acid coating acts as a hydrophobic coating that can prevent the calcium carbonate from absorbing the composition's constituents and rendering them ineffective. The hydrophobic coating of the calcium carbonate can represent from 0.1% to 3.5% by weight, based on the total weight of calcium carbonate.

[0144] Preferably, the fatty acids coating the calcium carbonate comprise or consist of more than 50% by weight of stearic acid relative to the total weight of fatty acids. Examples of precipitated calcium carbonate coated with fatty acids include HAKUENKA® CCR-S10 (marketed by OMYA) or CALOFORT® SV14 (marketed by Specialty Minerals).

[0145] Advantageously, the zeolites are chosen from synthetic zeolites of type A, X and / or Y, preferably of type A, and have a pore diameter of between 3 Å and 5 Å, preferably 3 Å.

[0146] According to a preferred embodiment, the filler (C) is precipitated calcium carbonate coated with fatty acids and / or a synthetic type A zeolite having a pore diameter of 3 Å.

[0147] Advantageously, the filler content (C) ranges from 1% to 25% by weight relative to the total weight of the composition (B), preferably from 2% to 20% by weight, more preferably from 4% to 15% by weight, even more preferably from 6% to 11% by weight.

[0148] Thermally conductive charae

[0149] The thermally conductive filler allows heat to be diffused thanks to its thermal conductivity value. In particular, the thermally conductive filler has a thermal conductivity greater than or equal to 3 W / mK, preferably greater than or equal to 5 W / mK, more preferably greater than or equal to 10 W / mK.

[0150] The thermal conductivity of the conductive filler may be determined by any method known to those skilled in the art. Advantageously, the thermal conductivity is determined according to ASTM D5740.

[0151] Advantageously, the thermally conductive filler is electrically insulating. By “electrically insulating” is meant in particular an electrical conductivity less than or equal to 0.1 S / m at 23°C, preferably less than or equal to 0.01 S / m at 23°C.

[0152] The thermally conductive filler makes it possible to confer good thermal conductivity to the thermally conductive two-component composition according to the invention.

[0153] Thus, the thermal conductivity of composition (A) and / or composition (B) is advantageously between 0.5 and 3 W / mK, preferably between 1.0 and 2.0 W / mK, more preferably equal to approximately 1.5 W / mK.

[0154] The thermal conductivity of compositions (A) and (B) is preferably determined following the ASTM D5470 method.

[0155] The moisture content of the thermally conductive filler is advantageously less than 0.05% by weight relative to the total weight of the thermally conductive filler, preferably less than 0.03% by weight. The moisture content can be determined according to the Karl Fisher method by determining the equivalence point electrometrically, for example by following the protocol described in Example 1 below.

[0156] The at least one thermally conductive filler may be chosen from aluminosilicates, alumina, aluminum hydroxide, aluminum nitride, boron nitride, zinc oxide, magnesium oxide and mixtures thereof, advantageously from aluminosilicates, alumina, aluminum hydroxide, boron nitride, zinc oxide, magnesium oxide and mixtures thereof, preferably from aluminosilicates, alumina, aluminum hydroxide and mixtures thereof, more preferably from aluminosilicates and mixtures thereof.

[0157] The thermally conductive filler is preferably of natural origin (i.e. it is not synthetic).

[0158] The thermally conductive filler advantageously does not have a three-dimensional crystalline structure having pores of at least 3 Å in diameter.

[0159] Preferably, composition (A) and / or composition (B) comprises at least two thermally conductive fillers.

[0160] Advantageously, the total content of thermally conductive filler(s) in composition (A) ranges from 50% to 90% by weight relative to the total weight of composition (A), preferably from 60% to 87% by weight, more preferably from 65% to 85% by weight, even more preferably from 70% to 80% by weight.

[0161] Advantageously, the total content of thermally conductive filler(s) in composition (B) ranges from 50% to 90% by weight relative to the total weight of composition (B), preferably from 60% to 87% by weight, more preferably from 65% to 85% by weight, even more preferably from 70% to 80% by weight.

[0162] According to a preferred embodiment, each of the compositions (A) and (B) comprises at least one thermally conductive filler. Preferably, each of the compositions (A) and (B) comprises at least two thermally conductive fillers.

[0163] Advantageously, the thermal conductivity of each of the compositions (A) and (B) is between 0.5 and 3 W / mK, preferably between 1.0 and 2.0 W / mK, more preferably equal to approximately 1.5 W / mK.

[0164] Advantageously, the total content of thermally conductive filler(s) in each of the compositions (A) and (B) ranges from 50% to 90% by weight relative to the total weight of each of the compositions (A) and (B), preferably from 60% to 87% by weight, more preferably from 65% to 85% by weight, even more preferably from 70% to 80% by weight. According to one embodiment, the composition (A) and / or the composition (B), preferably each of the compositions (A) and (B), comprises at least two thermally conductive fillers, the thermally conductive fillers in said composition having a different particle size. Advantageously, the difference in particle size d50 between two of the thermally conductive fillers is between 3 μm and 25 μm, preferably between 5 μm and 20 μm, more preferably between 10 μm and 14 μm.

[0165] The d50 particle size is well known to those skilled in the art as the maximum size of 50% of the smallest particles by volume, and can be measured with a particle size analyzer, in particular by laser diffraction on a MALVERN type device (for example according to standard NF ISO 13320).

[0166] Membership Promoter

[0167] Composition (A) and / or composition (B) may further comprise at least one adhesion promoter.

[0168] Advantageously, the adhesion promoter is chosen from amino-, mercapto- and epoxy-alkoxysilanes, preferably from aminoalkoxysilanes, more preferably from aminotrialkoxysilanes, even more preferably from aminotrimethoxysilanes, for example 3-aminopropyltrimethoxysilane.

[0169] An example of an epoxy-alkoxysilane is (3-glycidyloxypropyl)trimethoxysilane (also known as GLYMO).

[0170] Advantageously, the aminotrimethoxysilanes are formed by the group consisting of 4-amino-3,3-dimethylbutyltrimethoxysilane (for example SILQUEST A-LINK 600 marketed by MOMENTIVE), (3-aminopropyl)trimethoxysilane (for example DYNASYLAN® AMMO marketed by EVONIK) and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (for example DYNASYLAN® DAMO or DAMO-T marketed by EVONIK). Preferably, the aminotrimethoxysilanes are (3-aminopropyl)trimethoxysilane.

[0171] The content of adhesion promoter may range from 0.1% to 3% by weight relative to the total weight of composition (A), preferably from 0.2% to 2% by weight, more preferably from 0.5% to 1.5% by weight.

[0172] The content of adhesion promoter may range from 0.1% to 3% by weight relative to the total weight of composition (B), preferably from 0.2% to 2% by weight, more preferably from 0.5% to 1.5% by weight.

[0173] According to one embodiment, the content of adhesion promoter in each of the compositions (A) and (B) ranges from 0.1% to 3% by weight relative to the total weight of each of the compositions (A) and (B), preferably from 0.2% to 2% by weight, more preferably from 0.5% to 1.5% by weight.

[0174] Advantageously, composition (A) and / or composition (B) comprises at least one adhesion promoter.

[0175] Preferably, the adhesion promoter is in composition (A) only.

[0176] Crosslinking catalyst

[0177] Composition (B) may further comprise a crosslinking catalyst.

[0178] The crosslinking catalyst may be any catalyst known to those skilled in the art for silanol condensation. Examples of such catalysts include:

[0179] - organic titanium derivatives such as titanium acetyl acetonate (for example TYZOR® AA75 marketed by Dorf Ketal),

[0180] - aluminum such as aluminum chelate (for example K-KAT® 5218 marketed by KING INDUSTRIES),

[0181] - amines such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), diethyl ether-2,2'-morpholine (DMDEE), 1,4-diazabicylo[2.2.2]octane (DABCO),

[0182] - catalysts based on zinc carboxylate and DBU (for example K-KAT® 670 marketed by KING INDUSTRIES),

[0183] - tin-based catalysts such as compounds derived from dioctyltin or dibutyltin; in particular dioctyltin oxide, dioctyltin diacetate, dioctyltin dilaurate, dioctyltin dicarboxylate, dibutyltin diacetylacetonate (DBTDAA), dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin oxide or the product resulting from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate, preferably the product resulting from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate. Examples include NEOSTANN® S-1 (marketed by KANEKA), or TIB KAT® 425 or TIB KAT® 423 (marketed by TIB CHEMICALS).

[0184] Advantageously, the crosslinking catalyst is a tin-based catalyst, for example derived from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate.

[0185] Preferably, the crosslinking catalyst is a tin-based catalyst chosen from compounds derived from dioctyltin and dibutyltin, more preferably the tin-based catalyst is derived from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate (CAS No.: 93925-43-0).

[0186] The content of crosslinking catalyst may range from 0.01% to 1.5% by weight relative to the total weight of composition (B), preferably from 0.02% to 1.0% by weight, more preferably from 0.1% to 0.5% by weight.

[0187] Advantageously, composition (B) comprises a crosslinking catalyst.

[0188] Flame retardant

[0189] Composition (A) and / or composition (B) may further comprise a flame retardant.

[0190] Preferably, the flame retardant is chosen from triarylphosphates, trialkylphosphates and mixtures thereof, more preferably from tricresylphosphate, cresyldiphenylphosphate, tributylphosphate, trioctylphosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and mixtures thereof, even more preferably, cresyldiphenylphosphate.

[0191] The flame retardant content may range from 1% to 20% by weight relative to the total weight of composition (B), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0192] The flame retardant content may range from 1% to 20% by weight relative to the total weight of composition (A), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0193] The flame retardant content in each of compositions (A) and (B) may range from 1% to 20% by weight relative to the total weight of each of compositions (A) and (B), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0194] Advantageously, composition (A) and / or composition (B) comprises a flame retardant.

[0195] Preferably, the flame retardant is in composition (B) only.

[0196] Other additives

[0197] The thermally conductive two-component composition according to the invention may further comprise at least one additive. The additive may be in composition (A) and / or (B). Preferably, the additive is chosen from plasticizers, solvents, UV stabilizers and mixtures thereof. Advantageously, the thermally conductive two-component composition according to the invention comprises a mixture of additives chosen from plasticizers, solvents and UV stabilizers (or antioxidants).

[0198] Water is not considered a solvent for the purposes of the invention.

[0199] The total content of additives may range from 0.1% to 10% by weight relative to the total weight of the two-component thermally conductive composition, preferably from 1% to 5% by weight, more preferably from 2% to 3% by weight.

[0200] Advantageously, the two-component thermally conductive composition according to the invention comprises an additive chosen from plasticizers.

[0201] By "an additive chosen from plasticizers" is meant a plasticizer which may be plasticizer (b) in composition (B), and / or a plasticizer which may be plasticizer (b) in composition (A) when composition (A) does not comprise a rheology agent (r2), or a second plasticizer other than plasticizer (b) in composition (A) when composition (A) comprises a rheology agent (r2).

[0202] Preferably, the additive chosen from plasticizers is introduced into composition (B).

[0203] The additive chosen from among the plasticizers can be any plasticizer usually used in the field of adhesive compositions.

[0204] Preferably, this plasticizer is chosen from:

[0205] - diisodecyl phthalate (for example PALATINOL® DIDP marketed by BASF),

[0206] - diisononyl phthalate (DINP) (for example PALATINOL® N marketed by BASF),

[0207] - an ester of alkylsulfonic acid and phenol (for example MESAMOLL® marketed by LANXESS),

[0208] - diisononyl hexahydrophthalate (for example HEXAMOLL DINCH® marketed by BASF), and

[0209] - pentaerythritol tetravalerate (for example PEVALEN™ marketed by PERSTORP).

[0210] More preferably, this plasticizer is diisononyl hexahydrophthalate (CAS No.: 166412-78-8).

[0211] According to a preferred embodiment, the content of additive chosen from plasticizers ranges from 1% to 15% by weight relative to the total weight of composition (B), preferably from 2% to 10% by weight, more preferably from 3% to 7% by weight. The thermally conductive two-component composition according to the invention may comprise from 0% to 5% by weight of a solvent relative to the total weight of said composition, preferably a solvent that is volatile at room temperature (temperature of the order of 23°C). The volatile solvent may, for example, be chosen from alcohols that are volatile at room temperature, such as ethanol or isopropanol. Preferably, the thermally conductive two-component composition comprises from 0% to 1% by weight of a solvent relative to the total weight of said composition, more preferably from 0% to 0.5% by weight.

[0212] Advantageously, the thermally conductive two-component composition according to the invention comprises up to 1% by weight of one or more UV stabilizers (or antioxidants) relative to the total weight of said composition, preferably up to 0.5% by weight. The UV stabilizers are typically introduced to protect the composition from degradation resulting from a reaction with oxygen which is likely to form by the action of heat or light. These compounds may include antioxidants capable of trapping free radicals.

[0213] Advantageously, the UV stabilizer(s) (or antioxidants) are chosen from benzotriazoles, benzophenones, so-called hindered amines such as bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate (CAS No.: 41556-26-7), methyl 1,2,2,6,6-pentametiyl-4-piperidyl sebacate (CAS No.: 82919-37-7), octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 4,4'-bis(a,a-dimethylbenzyl)diphenylamine, and mixtures thereof. Examples include IRGANOX 1076, TINUVIN® 292, TINUVIN® 765 or TINUVIN® 770 DF products marketed by BASF, RIASORB UV-123 marketed by RIANLON and OKABEST CLX 50 marketed by OKA.

[0214] Preferably, the UV stabilizer(s) (or antioxidant(s)) are chosen from so-called hindered amines such as bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 4,4'-bis(a,a-dimethylbenzyl)diphenylamine, and mixtures thereof.

[0215] More preferably, the UV stabilizers (or antioxidants) are a mixture of bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and 4,4'-bis(a,a-dimethylbenzyl)diphenylamine.

[0216] Advantageously, the two-component thermally conductive composition according to the invention does not comprise a moisture absorber, in particular chosen from vinyltrimethoxysilane, vinyltriethoxysilane, alkoxyarylsilanes and p-toluenesulfonyl isocyanate.

[0217] Other characteristics of the two-component thermally conductive composition according to the invention

[0218] Advantageously, the volume ratio of composition (A) relative to composition (B) is between 0.25 and 4, preferably between 0.5 and 2, more preferably between 0.8 and 1.2, for example equal to 1.0.

[0219] Advantageously, composition (B) does not comprise water.

[0220] By "does not include water" is meant a composition in which the presence of water is solely due to the presence of moisture in the ingredients of the composition (no added water).

[0221] Advantageously, composition (B) has a moisture content of less than 1% by weight relative to the total weight of composition (B), preferably less than 0.8% by weight, more preferably less than 0.5% by weight, even more preferably less than or equal to 0.2% by weight.

[0222] The moisture content of composition (B) can be determined by adding together the moisture contents provided by each of the ingredients constituting it. Preferably, only filler (C) has a significant moisture content, i.e. at least 0.05% by weight relative to the total weight of filler (C). Thus, the moisture content of composition (B) preferably corresponds to the moisture content provided by filler (C).

[0223] According to one embodiment, the thermally conductive two-component composition according to the invention comprises:

[0224] - from 3% to 40% by weight of silylated polymer in composition (A), relative to the total weight of composition (A),

[0225] - from 0.2% to 15% by weight of rheology agent (r1) and / or (r2) in composition (A) and / or in composition (B), preferably in composition (A), preferably (r2), relative to the total weight of said composition (A) or (B),

[0226] - from 1% to 25% by weight of filler (C) in composition (B), relative to the total weight of composition (B), filler (C) providing between 0.0025% and 1% by weight of moisture relative to the total weight of composition (B),

[0227] - from 50% to 90% by weight of thermally conductive filler(s) in each of compositions (A) and (B), relative to the total weight of each of compositions (A) and (B), - from 0.1% to 3% by weight of adhesion promoter in composition (A) and / or in composition (B), preferably in composition (A), relative to the total weight of said composition (A) or (B),

[0228] - from 0.01% to 1.5% by weight of crosslinking catalyst in composition (B), relative to the total weight of composition (B),

[0229] - from 1% to 20% by weight of flame retardant in composition (A) and / or in composition (B), preferably in composition (B), relative to the total weight of said composition (A) or (B), and

[0230] - from 0.1% to 10% by weight of one or more additives chosen from plasticizers, solvents, UV stabilizers and their mixtures, relative to the total weight of the thermally conductive two-component composition, the volume ratio of composition (A) relative to composition (B) being between 0.25 and 4.

[0231] Preferably, the thermally conductive two-component composition according to the invention consists essentially of the ingredients mentioned above. By "consisting essentially", it is meant that the thermally conductive two-component composition according to the invention comprises less than 5% by weight of ingredients other than the aforementioned ingredients, relative to the total weight of said composition, preferably less than 2% by weight, even more preferably less than 1% by weight.

[0232] The ingredients of this embodiment and their particular contents are as described above, including the embodiments.

[0233] According to one embodiment, the thermally conductive two-component composition according to the invention comprises:

[0234] - from 3% to 40% by weight of silylated polymer in composition (A), relative to the total weight of composition (A),

[0235] - from 0.2% to 15% by weight of rheology agent (r1) and / or (r2) in composition (A), preferably (r2), relative to the total weight of composition (A),

[0236] - from 1% to 25% by weight of filler (C) in composition (B), relative to the total weight of composition (B), filler (C) providing between 0.0025% and 1% by weight of moisture relative to the total weight of composition (B),

[0237] - from 50% to 90% by weight of thermally conductive filler(s) in each of compositions (A) and (B), relative to the total weight of each of compositions (A) and (B), - from 0.1% to 3% by weight of adhesion promoter in composition (A) and / or in composition (B), preferably in composition (A), relative to the total weight of said composition (A) or (B),

[0238] - from 0.01% to 1.5% by weight of crosslinking catalyst in composition (B), relative to the total weight of composition (B),

[0239] - from 1% to 20% by weight of flame retardant in composition (A) and / or in composition (B), preferably in composition (B), relative to the total weight of said composition (A) or (B), and

[0240] - from 0.1% to 10% by weight of one or more additives chosen from plasticizers, solvents, UV stabilizers and their mixtures, relative to the total weight of the thermally conductive two-component composition, the volume ratio of composition (A) relative to composition (B) being between 0.25 and 4.

[0241] Preferably, the two-component thermally conductive composition according to the invention consists essentially of the ingredients mentioned above.

[0242] The ingredients of this embodiment and their particular contents are as described above, including the embodiments.

[0243] According to a particular embodiment, the two-component thermally conductive composition according to the invention comprises:

[0244] - from 17% to 22% by weight of silylated polymer in composition (A), relative to the total weight of composition (A), the silylated polymer preferably being a polymer of formula (III'),

[0245] - from 1% to 5% by weight of rheology agent (r2) in the composition (A), relative to the total weight of the composition (A), the rheology agent (r2) comprising: o from 5 to 30% by weight of a bis-urea (a) obtained by reaction of an n-alkylamine (a1) comprising from 1 to 22 carbon atoms with a diisocyanate (a2) of formula (V) in which R 6is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, relative to the total weight of said rheology agent (r2), and o from 70 to 90% by weight of a plasticizer (b) chosen from diisodecyl phthalate, di(2-propylheptyl) phthalate and their mixtures, relative to the total weight of said rheology agent (r2),

[0246] - from 6% to 11% by weight of filler (C) providing between 0.015% and 0.1% by weight of moisture in the composition (B), the percentages by weight being relative to the total weight of the composition (B), the filler (C) being chosen from carbonated fillers, zeolites and their mixtures, in particular the filler (C) is precipitated calcium carbonate coated with fatty acids and / or a synthetic zeolite of the type having a pore diameter of 3 Å,

[0247] - from 70% to 80% by weight of thermally conductive filler(s) chosen from aluminosilicates and their mixtures in each of compositions (A) and (B), relative to the total weight of each of compositions (A) and (B),

[0248] - from 0.5% to 1.5% by weight of adhesion promoter chosen from aminotrimethoxysilanes in composition (A), relative to the total weight of composition (A),

[0249] - from 0.1% to 0.5% by weight of crosslinking catalyst in composition (B), relative to the total weight of composition (B), the crosslinking catalyst being a tin-based catalyst,

[0250] - from 8% to 15% by weight of flame retardant in composition (B), relative to the total weight of composition (B), the flame retardant being chosen from tricresylphosphate, cresyldiphenylphosphate, tributylphosphate, trioctylphosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and mixtures thereof, and

[0251] - from 2% to 3% by weight of one or more additives chosen from plasticizers, solvents, UV stabilizers and their mixtures, relative to the total weight of the thermally conductive two-component composition, the volume ratio of composition (A) relative to composition (B) being between 0.8 and 1.2.

[0252] Preferably, the two-component thermally conductive composition according to the invention consists essentially of the ingredients mentioned above.

[0253] The ingredients of this embodiment and their particular contents are as described above, including the embodiments.

[0254] Advantageously, the two-component thermally conductive composition according to the invention has very good reactivity, that is to say that the crosslinking of the silylated polymer after mixing the compositions (A) and (B) occurs rapidly.

[0255] This reactivity can be determined by measuring the open time of the two-component thermally conductive composition according to the invention.

[0256] By "open time" is meant the time between the start of mixing compositions (A) and (B) and the start of crosslinking of the thermally conductive two-component composition, during which time the user can apply said thermally conductive two-component composition to the substrate(s) that he wishes to assemble. Preferably, the open time of the thermally conductive two-component composition according to the invention is less than 30 minutes, more preferably less than or equal to 15 minutes.

[0257] The open time is preferably determined as described in Example 1 below.

[0258] Advantageously, the viscosity at 21°C of the thermally conductive two-component composition according to the invention is less than or equal to 300,000 cP, preferably between 100,000 cP and 280,000 cP.

[0259] Advantageously, the viscosity at 21°C of the two-component thermally conductive composition according to the invention is determined immediately after it is obtained at 20 rpm (revolutions per minute) and using a Brookfield RVT viscometer and a size 7 needle.

[0260] The creep of the two-component thermally conductive composition according to the invention is advantageously less than 1 inch at 23°C. The creep can be determined according to the ASTM D2202 standard. thermally conductive according to the invention

[0261] Each of the compositions (A) and (B) of the two-component thermally conductive composition according to the invention is prepared separately, by simple mixing of its ingredients, preferably under vacuum.

[0262] By "vacuum" is meant a pressure lower than atmospheric pressure, advantageously between 10 kPa and 90 kPa, preferably between 50 kPa and 85 kPa, more preferably between 60 kPa and 80 kPa.

[0263] Advantageously, the two-component thermally conductive composition according to the invention is prepared without adding free water, that is to say other than that inherently included in the ingredients of the composition.

[0264] According to a preferred embodiment, composition (A) is prepared according to the following process:

[0265] 1) the silylated polymer is mixed, in a suitable container, with the possible adhesion promoter and / or flame retardant and with the possible additives such as plasticizer, solvent and UV stabilizer (or antioxidant), preferably at a temperature between 18°C ​​and 28°C and under vacuum, then - 2) the possible thermally conductive filler(s) are dispersed in the previous mixture at the same pressure, until a homogeneous mixture is obtained, then

[0266] - 3) the possible rheology agent is added at the same pressure and the medium is homogenized.

[0267] According to a preferred embodiment, composition (B) is prepared according to the following process:

[0268] 1) the possible adhesion promoter and / or flame retardant and any additives such as plasticizer, solvent and UV stabilizer (or antioxidant) are mixed, preferably at a temperature between 18°C ​​and 28°C and under vacuum, then

[0269] - 2) the filler (C) and the possible thermally conductive filler(s) are dispersed in the previous mixture at the same pressure, until a homogeneous mixture is obtained, then

[0270] - 3) the possible rheology agent is added at the same pressure and the medium is homogenized, then

[0271] - 4) the possible crosslinking catalyst is added at the same pressure and the medium is homogenized.

[0272] Preferably, the temperature during the preparation of composition (B) is less than or equal to 50°C, more preferably less than or equal to 45°C, even more preferably less than or equal to 40°C.

[0273] An example of preparation of compositions (A) and (B) and of the thermally conductive two-component composition according to the invention is described in Example 3.

[0274] Compositions (A) and (B) can be packaged, for example, in a dual cartridge. The thermally conductive dual-component composition is then advantageously dispensed using a dual-cartridge gun. A homogeneous mixture of the two components is obtained by attaching, for example, a static mixer to the dual cartridge.

[0275] Other objects of the present invention

[0276] The present invention also relates to the use of the two-component thermally conductive composition according to the invention as an adhesive and / or sealant, preferably as an adhesive.

[0277] Furthermore, the present invention also relates to the use of the thermally conductive two-component composition according to the invention as an adhesive in the field of building construction, in the field of manufacturing means of transport, preferably in the automobile, railway and aerospace industries, and in the field of shipbuilding, more particularly for assemblies intended for the manufacture of batteries, in particular rechargeable batteries for electric cars or hybrid cars.

[0278] The present invention also relates to the use of the thermally conductive two-component composition according to the invention for improving the lifespan of a battery, preferably a rechargeable battery.

[0279] Furthermore, the invention relates to the use of a filler (C) having a moisture content of between 0.05% and 5% by weight, relative to the total weight of the filler (C), for crosslinking without adding free water of a two-component composition, the two-component composition comprising a composition (A) comprising a silylated polymer, and a composition (B) comprising said filler (C).

[0280] “Free water” means water added to the two-component composition other than that inherently included in the ingredients of said composition.

[0281] The filler (C), the composition (A), the composition (B) and the silylated polymer are advantageously as defined above, including the embodiments. In particular, the filler (C) has a moisture content preferably between 0.1% and 3% by weight, more preferably between 0.10% and 2%, relative to the total weight of the filler (C).

[0282] Advantageously, the two-component composition is a thermally conductive two-component composition as described above.

[0283] Advantageously, the filler (C) is used for the rapid crosslinking of a two-component composition, that is to say that the use of the filler (C) makes it possible to obtain an open time for said two-component composition of less than 30 minutes, preferably less than or equal to 15 minutes.

[0284] The open time is as defined above.

[0285] The present invention also relates to an article, in particular a battery, comprising the thermally conductive two-component composition according to the invention.

[0286] Preferably, the article according to the invention is a battery, in particular a rechargeable battery, more preferably for an electric or hybrid car.

[0287] Finally, the present invention relates to a method of assembling two substrates by gluing, comprising:

[0288] - coating on at least one of the two substrates to be assembled the thermally conductive two-component composition according to the invention, then

[0289] - the effective contacting of the two substrates. The substrates concerned are very varied and are, for example, inorganic substrates such as concrete, metals or alloys (such as aluminum alloys, steel, non-ferrous metals and galvanized metals); or organic substrates such as wood, plastics such as PVC, polycarbonate, PMMA, polyethylene, polypropylene, polyesters, epoxy resins; or metal substrates and composites coated with paint (as in the automotive field for example). Preferably, the substrates are metals and / or plastics.

[0290] All the embodiments described above can be combined with each other. In particular, the various aforementioned ingredients of the thermally conductive two-component composition according to the invention, and in particular the preferred embodiments, can be combined with each other.

[0291] The following examples are given purely for illustrative purposes of the invention and should not be interpreted as limiting its scope.

[0292] Examples

[0293] Ingredients and measurement methods

[0294] Ingredients used

[0295] The following ingredients were used:

[0296] - MS POLYMER™ SAX 520 marketed by KANEKA: poly(propylene oxide) with trimethoxysilane ends with a number-average molar mass of between 29,000 and 31,000 g / mol, and a viscosity of 46 Pa.s;

[0297] DYNASYLAN® AMMO marketed by EVONIK: (3-aminopropyl)trimethoxysilane (CAS No.: 13822-56-5), adhesion promoter;

[0298] - CALOFORT® SV14 marketed by Specialty Minerals: precipitated calcium carbonate coated with fatty acids, having an average particle size of 70 nm and a moisture content of 0.2% by weight relative to the total weight of CALOFORT, charge (C);

[0299] - RIASORB UV-123 marketed by RIANLON: bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate (CAS No.: 129757-67-1), hindered amine light stabilizer (HALS);

[0300] - TINUVIN 770 DF marketed by BASF: bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate (CAS No.: 52829-07-9), hindered amine light stabilizer (HALS); - NEOSTANN S-1 marketed by KANEKA: product resulting from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate (CAS No.: 93925-43-0), crosslinking catalyst;

[0301] - Hexamoll® DINCH marketed by BASF: diisononyl hexahydrophthalate, plasticizer;

[0302] - n-butylamine, primary aliphatic amine used for the preparation of the rheology agent (r2);

[0303] - diisodecyl phthalate (DIDP), plasticizer (b) used for the preparation of the rheology agent (r2);

[0304] - 4,4'-diphenylmethane diisocyanate (4,4'-MDI), diisocyanate used for the preparation of the rheology agent (r2);

[0305] - Disflamoll® DPK marketed by LANXESS: cresyldiphenylphosphate (CDP), flame retardant;

[0306] - Siliporite® SA 1720 marketed by ARKEMA: synthetic zeolite of type A having a pore diameter of 3 Å and a moisture content of 1% by weight relative to the total weight of Siliporite, charge (C);

[0307] - SILATHERME® 1466-126 and SILATHERME® 1466-506 marketed by The Minerals Engineers: aluminosilicates with a d50 particle size of 21 pm and 9 pm respectively, thermally conductive fillers;

[0308] - AEROSIL® 150 marketed by EVONIK: fumed silica, rheology agent.

[0309] Measurement methods

[0310] The moisture content of each charge (C) (CALOFORT® SV14 and Siliporite® SA 1720) is determined using an 870 KF Titrino plus titrator and an 803 Tl stand stirring module, according to the Karl Fisher method as follows.

[0311] The titrant is HYDRANAL™ - Composite 5 (marketed by Honeywell), which contains 2-(2-ethoxyethoxy)ethanol and 4.5 - 5.5 mg of water per mL of titrant. The exact water content of the titrant is checked using a calibration solution comprising 1 mg of water per g of calibration solution (HYDRANAL™ - CRM Water Standard 1.0 marketed by Honeywell), using the titrator's "titer Ipol" program.

[0312] The titrator's "KFT Ipol" program is then used to determine the moisture content of the feed (C). The first step of the program is an automatic conditioning step where the traces of water in approximately 50 mL of dry methanol (HYDRANAL™ - Methanol dry marketed by Honeywell) are neutralized by the titrating agent in the stirring module tank. Next, a known mass (approximately 1 g) of feed (C) is introduced into the tank, then the exact mass introduced is entered into the program, and stirring is continued until the medium is homogeneous (approximately 1 to 10 min). Finally, the titration is carried out automatically and the moisture content of the feed (C) is displayed on the titrator screen.

[0313] Tensile strength and elongation at break were measured in accordance with ISO 37 (2005), at a constant speed of 500 mm / min.

[0314] In particular, the following conditions were applied:

[0315] A standard dumbbell-shaped test piece, type 2, as illustrated in international standard ISO 37 (2005) is used. The narrow part of the dumbbell used has a length of 20 mm, a width of 4 mm and a thickness of 3 to 4 mm.

[0316] To prepare the dumbbell, the composition to be tested is applied in a Teflon mold, and the composition is left to crosslink for 14 days under standard conditions (23°C and 50% relative humidity).

[0317] The principle of the measurement consists of stretching a standard test piece in a tensile machine, whose movable jaw moves at a constant speed equal to 500 mm / minute, and recording:

[0318] - the elongation at break (expressed in %) is the elongation of the specimen corresponding to the stretching observed at the time of break, and

[0319] - tensile strength (in MPa) is the tensile stress at which the specimen ruptures.

[0320] The measurement is repeated for 5 test pieces, and the corresponding average of the results obtained is calculated.

[0321] The open time is determined as the skin formation time. For this purpose, a bead of sealant (approximately 10 cm long and approximately 1 cm in diameter) is first placed on a cardboard support. Then, using a low-density polyethylene (LDPE) pipette tip, the surface of the sealant is touched every minute for up to 2 hours to determine the exact time at which the surface skin forms. This test is carried out under controlled humidity and temperature conditions (23 °C and 50% relative humidity).

[0322] Creep is determined at 23°C in accordance with ASTM D2202 and self-leveling is determined at 23°C by applying a bead of the two-component composition approximately 1 cm in diameter to a horizontal surface; the composition is self-leveling if the bead thickness decreases to 7 mm or less after 5 minutes.

[0323] Viscosity is determined immediately after obtaining the thermally conductive two-component composition at 20 rpm (revolutions per minute) and 21°C using a Brookfield RVT viscometer and a size 7 needle.

[0324] Thermal conductivity is measured in accordance with ASTM D5470.

[0325] The flammability index is determined in accordance with UL 94.

[0326] Example 2: Preparation of the rheology agent (r2)

[0327] Two solutions are prepared:

[0328] - a solution A of n-butylamine in DIDP, consisting of 17.17% by weight of n-butylamine and 82.83% by weight of DIDP, the percentages being on the total weight of solution A, then

[0329] - a solution B of 4,4'-MDI in DIDP, consisting of 29.46% by weight of 4,4'-MDI in 70.54% by weight of DIDP, the percentages being on the total weight of solution B.

[0330] The 2 solutions A and B are heated to 100°C, then introduced, each under a pressure of 100 bar, into a reactor, in which they are continuously sprayed onto each other in a ratio A / B = 50.1 / 49.9 by weight, corresponding to a molar ratio n-butylamine / MDI equal to 2. The reaction is immediate and the temperature of the reactor reaches 140°C at the end of manufacture.

[0331] At the reactor outlet, a stable dispersion of 23.3% by weight (relative to the total weight of the dispersion) in the DIDP of a bis-urea of ​​formula:

[0332] The Brookfield viscosity of the suspension measured at 23°C is 15 Pa.s.

[0333] Example 3: Composition 1 according to the invention comprising a composition 1A and a composition 1B

[0334] In a stirred reactor, the various ingredients of each of compositions 1 A and 1 B are mixed in the proportions indicated respectively in Tables 1 and 2 below, in several stages according to the method described below. The reactor is at room temperature (approximately 23°C) before adding the ingredients, and the temperature may increase when the ingredients are mixed. The temperature is advantageously controlled so as not to exceed 40°C during the preparation of composition 1 B.

[0335] The ingredients from step 1 are mixed under vacuum (between 60 kPa and 80 kPa) and at a stirring speed sufficient to homogenize.

[0336] Then, the ingredients from step 2 are slowly added to the reactor used for step 1, still under vacuum and at a stirring speed sufficient to homogenize.

[0337] Finally, the ingredients from step 3 are added to the reactor, still under vacuum and at a stirring speed sufficient to homogenize.

[0338] Table 1

[0339] Table 2

[0340] The moisture content provided by the filler (C) (CALOFORT® SV14) is 0.02% by weight relative to the total weight of composition 1 B.

[0341] Composition 1 according to the invention is then obtained by introducing compositions 1 A and 1 B into a double cartridge (protected from air and humidity), then mixing them using a dynamic mixer attached to the tip of the double cartridge, at room temperature (23°C) in a volume ratio equal to 1.0.

[0342] Example 4: Composition 2 according to the invention comprising a composition 2A and a composition 2B

[0343] In a reactor maintained under stirring, the different ingredients of each of compositions 2A and 2B are mixed in the proportions indicated respectively in Tables 3 and 4 below, in several stages according to the process described in Example 3.

[0344] Table 3

[0345] Table 4

[0346] The moisture content provided by the filler (C) (Siliporite® SA 1720) is 0.08% by weight relative to the total weight of composition 2B.

[0347] Composition 2 according to the invention is then obtained by introducing compositions 2A and 2B into a dual cartridge (protected from air and humidity), then mixing them using a dynamic mixer attached to the tip of the dual cartridge, at room temperature (23°C) in a volume ratio equal to 1.0.

[0348] Example 5: Comparative compositions 3 and 4

[0349] In a reactor maintained under stirring, the different ingredients of each of the compositions 3A, 3B, 4A and 4B are mixed in the proportions indicated respectively in Tables 5 and 6 below (the percentages are by weight on the total weight of each respective composition), in several stages according to the process described in Example 3.

[0350] Table 5

[0351] Table 6

[0352] The moisture content provided by the filler (C) (Siliporite® SA 1720) is approximately 0.08% by weight relative to the total weight of each composition 3B and 4B.

[0353] Comparative composition 3 is then obtained by introducing compositions 3A and 3B into a dual cartridge (protected from air and humidity), then mixing them using a dynamic mixer attached to the tip of the dual cartridge, at room temperature (23°C) in a volume ratio equal to 1.0.

[0354] Comparative composition 4 is obtained in a similar manner with compositions 4A and 4B.

[0355] Example 6: Mechanical properties of compositions 1-2 according to the invention and 3-4 comparative

[0356] The mechanical properties of compositions 1-2 according to the invention and 3-4 comparative (measured in accordance with Example 1) are summarized in Table 7 below. Table 7

[0357] Compositions 1 and 2 according to the invention have a very short open time (10 min at most). Thus, the compositions according to the invention crosslink quickly, while the moisture content provided by the filler (C) is very low.

[0358] Furthermore, the thermal conductivity of compositions 1 and 2 according to the invention allows their use in particular in assemblies intended for the manufacture of batteries.

[0359] Finally, the viscosity of compositions 1 and 2 allows easy application with a manual twin cartridge, without the need for a pneumatic gun, and their low creep associated with the fact that they are not self-leveling allows them to be applied in a non-horizontal position, limiting the risk of dripping.

[0360] In contrast, comparative composition 3, which does not include any rheology agent, has a flow greater than 1 inch and is self-leveling, meaning that it will tend to "flow" after application, even in a horizontal position; while comparative composition 4, which includes fumed silica as a rheology agent, has a viscosity too high to be easily applied with a manual dual cartridge.

[0361] Thus, compositions 1 and 2 according to the invention have the advantage of crosslinking quickly without adding free water, of being sufficiently heat-conductive, but also of being able to be applied easily with a manual dual cartridge while limiting the risk of dripping in a non-horizontal position.

Claims

Demands 1. Two-component thermally conductive composition comprising: - a composition (A) comprising: o a silylated polymer, and - a composition (B) comprising: o at least 1% by weight of a filler (C) relative to the total weight of the composition (B), the filler (C) contributing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler, and the composition (A) and / or the composition (B), preferably the composition (A), further comprising: o a rheology agent (r1) selected from amide waxes and / or o a rheology agent (r2) comprising: ■ from 1% to 40% by weight of a bis-urea (a) obtained by reaction of a primary aliphatic amine with a diisocyanate of molar mass less than 500 g / mol, relative to the total weight of the rheology agent (r2), and ■ from 60% to 99% by weight of a plasticizer (b) selected from alkyl phthalates, pentaerythritol tetravalerate, alkylsulfonic acid and phenol esters, diisononyl-1,2-cyclohexane dicarboxylate, 3,3'-[methylenebis(oxymethylene)]bis[heptane], dioctyl carbonate and mixtures thereof, relative to the total weight of the rheology agent (r2), said rheology agent (r2) being in the form of a suspension of solid particles of bis-urea (a) in a continuous phase of plasticizer (b).

2. Two-component thermally conductive composition according to claim 1, wherein the silylated polymer comprises at least one, preferably at least two, alkoxysilane groups of formula (I): -If(R 4 )p(OR 5 ) 3.P (I) in which: - R 4 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p equals 2, the R radicals 4are identical or different, - R 5 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p is equal to 0 or 1, the R radicals 5 are identical or different, two OR groups 5 that can be engaged in the same cycle, and - p is an integer equal to 0, 1 or 2, preferably equal to 0 or 1.

3. Two-component thermally conductive composition according to claim 1 or 2, wherein the silylated polymer is of formula (II), (III) or (IV): in which: - R 4 , R 5 and p have the same meaning as in formula (I) described above, - P represents a saturated or unsaturated polymeric radical, with a linear or branched open chain, or comprising one or more rings, possibly aromatic, possibly comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur and / or silicon, preferably oxygen and / or nitrogen, - R 1 represents a divalent hydrocarbon radical comprising 5 to 15 carbon atoms, saturated or unsaturated, with a linear or branched open chain, or comprising one or more possibly aromatic rings, R 3 represents a linear or branched alkylene divalent radical comprising 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, - X represents a divalent radical chosen from -NH-, -NR 7 - or -S-, - R 7 represents a linear or branched alkyl radical comprising from 1 to 20 carbon atoms and possibly also comprising one or more heteroatoms, - f is an integer from 1 to 6, advantageously from 2 to 5, preferentially from 2 to 4, even more preferably from 2 to 3.

4. Two-component thermally conductive composition according to claim 3, wherein the silylated polymer is of formula (IT), (II”), (III') or (IV'): in which: R 1 , R 3 , R 4 , R 5 , X, R 7 and p have the same meaning as in formulas (II), (III) and (IV), - R 2 represents a saturated or unsaturated, linear or branched, divalent hydrocarbon radical possibly comprising one or more heteroatoms, such as oxygen, nitrogen, sulfur, silicon, - n is an integer, preferably n is such that the number-average molecular mass of the silylated polymer is between 500 g / mol and 70000 g / mol, more preferably between 1000 g / mol and 60000 g / mol, even more preferably between 2000 g / mol and 50000 g / mol.

5. Two-component thermally conductive composition according to any one of claims 1 to 4, wherein the rheology agent (r2) is such that bis-urea (a) is obtained by reaction of an n-alkylamine (a1) comprising from 1 to 22 carbon atoms, preferably n-butylamine, with a diisocyanate (a2) of formula (V): NCO-R 6 -NCO (V) in which R 6 is chosen from one of the following divalent radicals, whose formulas below show the 2 free valences: - i) the divalent radical derived from isophorone: - ii) the divalent radical 4,4'-methylene-bis(cyclohexyl): - iii) the divalent radical derived from toluene 2,4-diisocyanate (or 2,4-TDI) or toluene 2,6-diisocyanate (or 2,6-TDI) with respective formulas: - iv) the divalent radical derived from diphenylmethylene 4,2'-diisocyanate (or 4,2'-MDI) or diphenylmethylene 4,4'-diisocyanate (or 4,4'-MDI), with respective formulas: And - v) the hexamethylene radical: -(CH2)6-, - vi) the m-xylylene radical: , and - vii) the hexahydro-m-xylylene radical:

6. Two-component thermally conductive composition according to any one of claims 1 to 5, wherein the filler (C) is selected from clays, talc, kaolins, gypsum, carbonate fillers, zeolites, expandable graphite and mixtures thereof.

7. Two-component thermally conductive composition according to any one of claims 1 to 6, wherein the filler (C) is precipitated calcium carbonate coated with fatty acids and / or a synthetic zeolite of type A having a pore diameter of 3 Å.

8. Two-component thermally conductive composition according to any one of claims 1 to 7, wherein at least one thermally conductive filler is selected from aluminosilicates, alumina, aluminum hydroxide, aluminum nitride, boron nitride, magnesium oxide and mixtures thereof, preferably from aluminosilicates, alumina, aluminum hydroxide and mixtures thereof, more preferably from aluminosilicates and mixtures thereof.

9. Two-component thermally conductive composition according to any one of claims 1 to 8, wherein each of the compositions (A) and (B) comprises at least one thermally conductive filler.

10. Two-component thermally conductive composition according to any one of claims 1 to 9, wherein composition (A) and / or composition (B) further comprises a flame retardant, preferably selected from triarylphosphates, trialkylphosphates and mixtures thereof, more preferably from tricresylphosphate, cresyldiphenylphosphate, tributylphosphate, trioctylphosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and mixtures thereof, even more preferably, cresyldiphenylphosphate.

11. Two-component thermally conductive composition according to any one of claims 1 to 10, wherein the volume ratio of composition (A) to composition (B) is between 0.25 and 4, preferably between 0.5 and 2, more preferably between 0.8 and 1.2, for example equal to 1.

0.

12. Use of the two-component thermally conductive composition according to any one of claims 1 to 11, to improve the service life of a battery, preferably a rechargeable battery.

13. Use of a charge (C) having a moisture content between 0.05% and 5% by weight, relative to the total weight of the filler (C), for crosslinking without the addition of free water of a two-component composition, the two-component composition comprising a composition (A) comprising a silylated polymer, and a composition (B) comprising said filler (C).

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