Two-component, thermally conductive silylated polymer composition

Abstract

The invention relates to a two-component thermally conductive composition comprising: a composition (A) comprising: a silylated polymer, and a rheology agent (r1) selected from amide waxes and / or a rheology agent (r2) comprising: from 1% to 40% by weight of a bis-urea (a) obtained by reacting 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 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 the bis-urea (a) in a continuous phase of plasticizer (b), 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) contributing at least 0.0025% by weight of moisture relative to the total weight of the composition (B),Composition (A) and / or composition (B) further comprising at least one thermally conductive filler. The invention also relates to the use of a filler (C) having a specific moisture content for crosslinking, without the addition of 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). Figure for the abstract: none.

Description

Title of the invention: Two-component, thermally conductive silylated polymer composition Scope of the invention

[0001] The present invention relates to a two-component, thermally conductive silylated polymer composition, and in particular to its use for improving battery life. The present invention also relates to the use of a filler (C) having a specific moisture content for crosslinking a two-component silylated polymer composition without the addition of free water. Technical background

[0002] Various polymer-based compositions are available on the market, which can be used in many fields, particularly as adhesives and / or sealants. Adhesives and sealants allow for the assembly (or joining or bonding) of two substrates, which can be chosen from a wide variety of materials.

[0003] For example, polymer-based compositions can be used as adhesives and / or sealants in building construction, shipbuilding, or the transport sector (e.g., road, sea, rail or aerospace).

[0004] Compositions based on alkoxysilane-terminated polymers (also called silylated polymers) have the advantage of being isocyanate-free. These compositions therefore constitute a toxicologically preferable alternative to isocyanate-terminated polyurethane compositions, which are very commonly found on the adhesives market.

[0005] 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.

[0006] Certain applications, particularly assemblies for battery manufacturing, require that the polymer-based composition have specific properties, especially in terms of thermal conductivity. Since battery charging is generally accompanied by a temperature increase, it is important to limit this increase as much as possible, as it can degrade certain electronic circuits or reduce the battery's lifespan. Therefore, it is important that the silylated polymer composition have sufficient thermal conductivity to mitigate these problems.

[0007] However, closed assemblies such as batteries do not allow enough air (and therefore moisture) to pass through for the polymer crosslinking reaction to occur. silylé takes place.

[0008] A two-component composition comprising, on the one hand, the silylated polymer to be crosslinked, and on the other hand, water, can be used as an adhesive. The two adhesive components are often packaged separately in the two compartments of a two-cartridge dispenser. The adhesive is then dispensed at the time of application onto the substrates to be bonded by extruding the two components, for example, using a two-cartridge gun, and following their homogeneous mixing, obtained, for example, by attaching a static mixer to the two-cartridge dispenser. The reaction of the component containing the silylated polymer with the component containing water enables the crosslinking of the silylated polymer.

[0009] However, water is hydrophilic while the silylated polymer is hydrophobic. Thus, a processability problem arises when mixing the components because it is difficult to mix the water-containing component with the silylated polymer component, as the water generally settles on the mixer blades.

[0010] There is therefore a need to provide a two-component silylated polymer composition that has both good thermal conductivity and good processability.

[0011] Furthermore, there is a need to provide a thermally conductive, two-component silylated polymer composition that crosslinks rapidly. This property can be evaluated by measuring the open time of the composition: the shorter it is, the faster the composition crosslinks. Summary of the invention

[0012] The present invention relates to a two-component thermally conductive composition comprising: - a composition (A) comprising: • a silylated polymer, and • a rheology agent (rl) selected from amide waxes and / or • 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 dii-socyanate of molar mass less than 500 g / mol, relative to the total weight of the rheology agent (r2), and • 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),

[0013] said rheology agent (r2) in the form of a suspension of solid bis-urea particles (a) in a continuous phase of plasticizer (b), 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) contributing at least 0.0025% by weight of moisture relative to the total weight of the composition (B),

[0014] the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler.

[0015] 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.

[0016] Furthermore, the present invention also aims at 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.

[0017] The present invention also relates to the use of the thermally conductive two-component composition according to the invention to improve the lifespan of a battery, preferably a rechargeable battery.

[0018] 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 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).

[0019] The present invention also relates to an article, in particular a battery, comprising the thermally conductive two-component composition according to the invention.

[0020] Finally, the present invention relates to a method for assembling two substrates by bonding, comprising:

[0021] - the coating on at least one of the two substrates to be assembled of the bi composition thermally conductive component according to the invention, then

[0022] - the effective contacting of the two substrates.

[0023] Surprisingly, it was found that incorporating a filler (C) into composition (B), providing at least 0.0025% by weight of moisture relative to the total weight of composition (B), not only improves the mixing of composition (A) with composition (B), thus limiting processability problems (in particular limiting water deposition on the mixer blades), but also leads to rapid crosslinking of the silylated polymer after contact with composition (A), without the need to add water. (free) in the composition (B). Description of the invention

[0024] Thus, the invention relates to a two-component thermally conductive composition comprising: - a composition (A) comprising: • a silylated polymer, and • a rheology agent (rl) selected from amide waxes and / or • 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 dii-socyanate 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),

[0025] said rheology agent (r2) in the form of a suspension of solid bis-urea particles (a) in a continuous phase of plasticizer (b), 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) contributing at least 0.0025% by weight of moisture relative to the total weight of the composition (B),

[0026] the composition (A) and / or the composition (B) further comprising at least one thermally conductive filler. Silyl polymer

[0027] The term "silylated polymer" means a polymer comprising at least one alkoxysilane group. Preferably, the silylated polymer comprises at least one alkoxysilane group at the polymer's termination.

[0028] 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.

[0029] The viscosity of the silylated polymer can for example be measured according to a Brookfield type method at 23°C and 50% relative humidity (needle S28).

[0030] In the context 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%.

[0031] Advantageously, the silylated polymer comprises at least one, preferably at least two, alkoxysilane groups of formula (I): (I)

[0032] in which: - R4 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p equals 2, the R4 radicals are either identical or different. - R5 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p is equal to 0 or 1, the R5 radicals are identical or different, two OR5 groups being able to be involved in the same ring, and - p is an integer equal to 0, 1 or 2, preferably equal to 0 or 1.

[0033] Preferably, the alkoxysilane groups of the silylated polymer have formula (I) with: - R4 and R5 each represent a methyl radical, and - p is equal to 0 or 1.

[0034] Advantageously, the silylated polymer has a number-average molecular mass of between 500 g / mol and 70000 g / mol, preferably between 1000 g / mol and 60000 g / mol, more preferably between 2000 g / mol and 50000 g / mol.

[0035] 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.

[0036] Advantageously, the silylated polymer has formula (II), (III) or (IV): in which: R4, R5 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, - R1 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, - R3 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-, -NR7- or -S-, - R7 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.

[0037] Advantageously, the silylated polymer is of formula (II), (III) or (IV) with P representing a polymeric radical selected from polyethers, polycarbonates, polyesters, polyolefins, polyacrylates, polyether polyurethanes, polyester polyurethanes, polyolefin polyurethanes, polyacrylate polyurethanes, polycarbonate polyurethanes, polyether / polyester block polyurethanes, preferably selected from polyethers, polyurethanes and their mixtures, more preferably from polyethers.

[0038] Preferably, the silylated polymer has the formula (II'), (II”), (III') or (IV'): 4r\s!-r— .nh-c—o—rh-o—c—mh-r—rh-c—o—rh-o—c—kh-R—stfR^MORA, „ p II L .1! Il X II ' O 0 0 " O

[0039] (II') - rQ-OC- NH- R^SKR4WRskj, n H OO

[0040] (II”) ?R^KJR^Si- R3- O- Rs4o- R3"" SW4WORS

[0041] (III') OOOO ' n O <3

[0042] (IV')

[0043] in which: - R1, R3, R4, R5, X, R7 and p have the same meaning as in formulas (II), (III) and (IV), - R2 represents a saturated or unsaturated, linear or divalent hydrocarbon radical (R^R4)^- Nile - C- O- R34O branched, 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.

[0044] In the silylated polymers of formulas (II'), (II”), (III'), or (IV') defined above, when the radical R2 comprises one or more heteroatoms, said heteroatom(s) are not located at the end of the chain. In other words, the free valences of the divalent radical R2, bonded to the neighboring oxygen atoms of the silylated polymer, each originate from a carbon atom. Thus, the main chain of the radical R2 terminates with a carbon atom at each of its two ends, said carbon atom then exhibiting a free valence.

[0045] According to one embodiment, the silylated polymers are obtained from polyols selected from polyether polyols, polyester polyols, polycarbonate polyols, polyacrylate polyols, polysiloxane polyols, polyolefin polyols and their mixtures, preferably from diols selected from polyether diols, polyester diols, polycarbonate diols, polyacrylate diols, polysiloxane diols, polyolefin diols and their mixtures, more preferably from polyether diols. In the case of polymers of formulas (II'), (II”), (III') or (IV') described above, such diols can be represented by the formula H0-R2-OH or H-[O-R2]n-OH, where R2 has the same meaning as in formulas (II'), (II”), (III') or (IV').

[0046] According to one embodiment, when the silylated polymer has formula (II') or (IV'), the radical R2 can be chosen from the following divalent radicals whose formulas below show the two free valences:

[0048] - derivative of a polybutadiene diol:

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059] - derived from a polyacrylate diol: qq 5 q ! —Q—If A4 Q - derived from a polysiloxane diol: in which: - q represents an integer such that the number molar mass of the radical R2 ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, and preferably again from 500 g / mol to 12600 g / mol, - r and s represent zero or a non-zero integer such that the number-average molar mass of the radical R2 ranges from 100 g / mol to 48600 g / mol, preferably from 300 g / mol to 18600 g / mol, preferably still from 500 g / mol to 12600 g / mol, it being understood that the sum r+s is not zero, - Q1 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, - Q2 represents a linear or branched divalent alkylene radical preferably having from 2 to 36 carbon atoms, preferably from 1 to 8 carbon atoms, - Q3, Q4, Q5, Q6, Q7 and Q8, represent, independently of each other, a hydrogen atom or an alkyl, alkenyl or aromatic radical, preferably having 1 to 12 carbon atoms, preferably 2 to 12 carbon atoms, preferably still 2 to 8 carbon atoms. According to one embodiment, R1 is chosen from the following divalent radicals whose formulas below show the two free valences: a) the divalent radical derived from isophorone diisocyanate (IPDI): b) the divalent radical derived from dicyclohexylmethane diisocyanate (H12MDI): / \........ / \ -( hŒH. >— \__ / \__ /

[0060] c) divalent radicals derived from the 2,4- and 2,6- isomers of toluene diisocyanate (TDI):

[0061] d) divalent radicals derived from the 4,4' and 2,4'- isomers of diphenylmethane diisocyanate (MDI):

[0062] e) the divalent radical derived from hexamethylene diisocyanate (HDI): -(CH2)6-

[0063] f) the divalent radical derived from m-xylylene diisocyanate (m-XDI):

[0064] According to a preferred embodiment, the silylated polymer is of formula (II”) or (III'), preferably (III'), and the radical R2 preferably represents a linear or branched alkylene divalent radical comprising 2 to 4 carbon atoms, more preferably a linear or branched alkylene divalent radical comprising 3 carbon atoms, even more preferably an isopropylene radical (of formula -CH2 -CH(CH3)-).

[0065] According to a particularly preferred embodiment, the silylated polymer is a polymer of formula (III') in which: - R2 represents an isopropylene radical, - R5 represents a methyl radical, and - p is equal to 0.

[0066] Polymers of formula (II), (II') or (II”) can be obtained by a process described, for example, in documents EP 2336208 and WO 2009 / 106699. Examples of polymers conforming to formula (II) include: GENIOSIL® STP-E10 (available from WACKER-CHEMIE): polyether of formula (II”) comprising two groups of formula (I) dimethoxy type (p equal to 1 and R4 and R5 represent a methyl group) having a number-average molar mass of 8889 g / mol where R3 represents a methyl group; GENIOSIL® STP-E30 (available from WACKER-CHEMIE): polyether of formula (II”) comprising two groups of formula (I) of dimethoxy type (p equal to 1 and R4 and R5 represent a methyl group) having a number-average molar mass of 14493 g / mol where R3 represents a methyl group; - DESMOSEAL® S XP 2636 (available from BAYER): polyurethane comprising two formula (I) groups of the trimethoxy type (p equals 0 and R5 represents a methyl group) having a number-average molar mass of 15038 g / mol where R3 represents an n-propylene group.

[0067] Polymers of formula (III) or (III') can be obtained by hydrosilylation of polyether diallylether according to a process described, for example, in document EP 1829928. Among the polymers corresponding to formula (III), the following may be mentioned:

[0068] - the MS SAX® 350 polymer (available from KANEKA) corresponding to a polyether comprising two formula (I) groups of dimethoxy type (p equal to 1 and R4 and R5 represent a methyl group) having a number-average molar mass ranging from 14000 to 16000 g / mol;

[0069] - the MS SAX® 260 polymer (available from KANEKA) corresponding to a polyether comprising two formula (I) groups of dimethoxy type (p equal to 1, R4 and R5 represent a methyl group) having a number average molar mass of 16000 to 18000 g / mol where R3 represents an ethyl group;

[0070] - the MS S303H polymer (available from KANEKA) corresponding to a polyether comprising two formula (I) groups of dimethoxy type (p is equal to 1 and R4 represents a methyl group) having a number average molar mass of 21000 to 23000 g / mol;

[0071] - the MS SAX® 520 polymer (available from KANEKA) corresponding to a polyether comprising formula (I) groups of the trimethoxy type (p equal to 0 and R5 represents a methyl group) having a number-average molar mass ranging from 29000 to 31000 g / mol.

[0072] Polymers of formula (IV) or (IV') can, for example, be obtained by reacting polyol(s) with one or more diisocyanates 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. Those skilled in the art will be able to adapt the manufacturing process described in this document when using different types of polyols. Examples of polymers corresponding to formula (IV) include: - SPUR+® 1050MM (available from MOMENTIVE): polyurethane comprising two formula (I) groups of trimethoxy type (p equal to 0 and R5 represents a methyl group) having a number-average molar mass of 16393 g / mol where R3 represents an n-propyl group; - SPUR+® Y-19116 (available from MOMENTIVE): polyurethane comprising two formula (I) groups of the trimethoxy type (p equals 0 and R5 represents a methyl group) having a number-average molar mass ranging from 15000 to 17000 g / mol g / mol where R3 represents an n-propyl group.

[0073] The content of silylated polymer in composition (A) can 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. Rheology agent

[0074] The total content of rheology agent in composition (A) can 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.

[0075] Preferably, composition (A) comprises a rheology agent (r2). Rheology agent (rl)

[0076] 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) (for example ricinoleic acid) and (di)amine(s).

[0077] 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.

[0078] The average particle size advantageously corresponds 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).

[0079] Unless otherwise indicated, the standards referred to throughout the application are those in force on the date of filing of the application.

[0080] Wax-amide type rheology agents are generally heat-activated, i.e. a temperature above ambient temperature (23°C) may be required to activate them during the preparation of the composition according to the invention.

[0081] The activation temperature depends on the rheology agent.

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089] Preferably, the activation temperature of the rheology agent (rl) is less than 80°C, more preferably less than 65°C, even more preferably less than 55°C. 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. Rheology agent (r2) Advantageously, the rheology agent (r2) is such that bis-urea (a) is obtained by reaction of an n-alkylamine (al) comprising from 1 to 22 carbon atoms, preferably n-butylamine, with a diisocyanate (a2) of formula (V): NCO-R6-NCO (V) in which R6 is chosen from one of the following divalent radicals whose formulas below show the 2 free valences: - i) the divalent radical derived from isophorone: CH3 CH 2— ' ch3J^ ch3 - 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:

[0090] - 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:

[0091] - v) the hexamethylene radical: -(CH2)6-,

[0092] - vi) the m-xylylene radical:

[0093] - vii) the hexahydro-m-xylylene radical: CH2

[0094] Preferably, the diisocyanate (a2) is of formula (V) in which R6 is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, preferably from 4,4'-MDI.

[0095] According to a preferred embodiment, bis-urea (a) is obtained by reaction of n-butylamine with a diisocyanate (a2) of formula (V) in which R6 is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, preferably from 4,4'-MDI.

[0096] As indicated above, the plasticizer (b) is 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.

[0097] Alkyl phthalates are preferably formed by the group consisting of diisodecyl phthalate (DIDP), di(2-propylheptyl) phthalate and mixtures thereof.

[0098] With regard to pentaerythritol tetravalerate, we can cite the product marketed under the brand name Pevalen® by the company Perstorp.

[0099] As regards an ester of alkylsulfonic acid and phenol, the product Mesamoll®, marketed by the company Lanxess, can be cited.

[0100] With regard to diisononyl-l,2-cyclohexane dicarboxylate, one can cite the product marketed under the name Hexamoll Dinch® by the company BASF.

[0101] 3,3'-[methylenebis(oxymethylene)]bis[heptane] can be identified by its CAS number: 22174-70-5 and is also known by the trade name 2-ethylhexylal, available from LAMBIOTTE.

[0102] Finally, dioctyl carbonate (EC No. 434-850-2) is available from BASF.

[0103] Advantageously, the rheology agent (r2) is such that the plasticizer (b) is chosen from alkyl phthalates, preferably the plasticizer (b) is chosen from diisodecyl phthalate, di(2-propylheptyl) phthalate and mixtures thereof, more preferably the plasticizer (b) is diisodecyl phthalate.

[0104] According to a preferred embodiment, the rheology agent (r2) consists of: - 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),

[0105] 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 bis-urea (a) and plasticizer (b) being as described above, including embodiments.

[0106] Advantageously, the rheology agent (r2) comprises, and preferably consists of, 5 to 30% by weight of bis-urea (a) and 70 to 95% by weight of plasticizer (b), the percentages being in relation to the total weight of said rheology agent (r2).

[0107] Bis-urea (a) and plasticizer (b) are as described above, including embodiments.

[0108] 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.

[0109] The reaction of the primary aliphatic amine with the diisocyanate is highly exothermic. To prevent the large amount of heat generated 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 generated 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 a sprayed liquid state. The quantities of reactants preferably correspond to a ratio (number of moles of aliphatic amine primary phatic) / (number of moles of diisocyanate) of about 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, being generally between 1 and 50 Pa.s, preferably between 10 and 25 Pa.s.

[0110] By "approximately X", we are aiming for plus or minus 10% of the value of X. Charge (C)

[0111] The charge (C) of the composition (B) includes residual moisture enabling the hydrolysis of the alkoxysilyl groups of the silylated polymer, which advantageously leads to crosslinking of the silylated polymer, without the need to add water to the composition (B).

[0112] The charge (C) is different from the thermally conductive charge.

[0113] Incorporating this filler (C) into composition (B) advantageously yields a more homogeneous two-component thermally conductive composition. Indeed, since composition (A) is hydrophobic, particularly due to the presence of the silylated polymer, its mixing with composition (B) is facilitated when water is supplied by filler (C).

[0114] 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.

[0115] 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.

[0116] The moisture provided by the filler (C) can be determined by taking into account the filler content (C) 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).

[0117] Advantageously, the moisture content of the charge (C) is between 0.05% and 5% by weight relative to the total weight of the charge (C), preferably between 0.1% and 3% by weight, more preferably between 0.10% and 2% by weight.

[0118] A person skilled in the art knows how to determine the moisture content of a charge (C). The moisture content of the charge (C) can be determined according to the Karl Fischer method by determining the equivalence point electrometrically. For example, the moisture content can be determined by following the protocol described in Example 1 below. After.

[0119] The average particle size of the charge (C) can range from 10 nm to 400 pm, preferably from 20 nm to 100 pm, more preferably from 30 nm to 50 pm.

[0120] The average particle size advantageously corresponds 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).

[0121] Advantageously, the filler (C) is chosen from clays, talc, kaolins, gypsum, carbonate fillers, zeolites, expandable graphite and mixtures thereof.

[0122] Preferably, the filler (C) is chosen from carbonate fillers, zeolites, expandable graphite and mixtures thereof, more preferably from carbonate fillers, zeolites and mixtures thereof.

[0123] 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.

[0124] When calcium carbonate is coated with fatty acids, this imparts total or partial hydrophobicity to the calcium carbonate particles. Furthermore, the fatty acid coating acts as a hydrophobic coating that can prevent the calcium carbonate from absorbing the constituents of the composition and rendering them ineffective. The hydrophobic coating of the calcium carbonate can represent from 0.1% to 3.5% by weight, relative to the total weight of calcium carbonate.

[0125] 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.

[0126] As an example of precipitated calcium carbonate coated with fatty acids, we can cite HAKUENKA® CCR-S10 (marketed by OMYA) or CALOFORT® SV14 (marketed by Specialty Minerais).

[0127] Advantageously, the zeolites are selected from synthetic zeolites of type A, X and / or Y, preferably of type A, and have a pore diameter between 3 Å and 5 Å, preferably of 3 Å.

[0128] According to a preferred embodiment, 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.

[0129] 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, and even more preferably from 6% to 11% by weight. weight. Thermally conductive charge

[0130] The thermally conductive load allows heat to be diffused thanks to its thermal conductivity value. In particular, the thermally conductive load 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.

[0131] The thermal conductivity of the conductive load can be determined by any method known to those skilled in the art. Advantageously, the thermal conductivity is determined according to ASTM D5740.

[0132] Advantageously, the thermally conductive charge is electrically insulating. By "electrically insulating", we mean 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.

[0133] The thermally conductive filler makes it possible to give good thermal conductivity to the two-component thermally conductive composition according to the invention.

[0134] Thus, the thermal conductivity of composition (A) and / or of composition (B) is advantageously between 0.5 and 3 W / mK, preferably between 1.0 and 2.0 W / mK, more preferably equal to about 1.5 W / mK.

[0135] The thermal conductivity of compositions (A) and (B) is preferably determined by following the ASTM D5470 method.

[0136] Advantageously, at least one thermally conductive filler is chosen 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

[0137] Preferably, composition (A) and / or composition (B) comprises at least two thermally conductive fillers.

[0138] 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.

[0139] 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.

[0140] 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.

[0141] 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 about 1.5 W / mK.

[0142] 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.

[0143] According to one embodiment, composition (A) and / or composition (B), preferably each of 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.

[0144] 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). Membership promoter

[0145] Composition (A) and / or composition (B) may further include at least one membership promoter.

[0146] Advantageously, the adhesion promoter is chosen from among amino-, mercapto- and epoxy-alkoxysilanes, preferably from aminoalkoxysilanes, more preferably from aminotrialkoxysilanes, even more preferably from aminotrimethoxysilanes, for example 3-aminopropyltrimethoxysilane.

[0147] As an example of an epoxy-alkoxysilane, we can cite (3-glycidyloxypropyl)trimethoxysilane (also known as GLYMO).

[0148] Advantageously, 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, aminotrimethoxysilanes are (3-aminopropyl)trimethoxysilane.

[0149] The content of adhesion promoter may range from 0.1% to 3% by weight relative to the total weight of the composition (A), preferably from 0.2% to 2% by weight, more preferably from 0.5% to 1.5% by weight.

[0150] The adhesion promoter content can 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.

[0151] 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.

[0152] Advantageously, composition (A) and / or composition (B) comprises at least one adhesion promoter.

[0153] Preferably, the adhesion promoter is in composition (A) only. Crosslinking catalyst

[0154] Composition (B) may further comprise a crosslinking catalyst.

[0155] The crosslinking catalyst can be any catalyst known to those skilled in the art for the condensation of silanol. Examples of such catalysts include:

[0156] - organic derivatives of titanium such as titanium acetyl acetonate (for example the TYZOR® AA75 marketed by Dorf Ketal),

[0157] - of aluminium such as aluminium chelate (for example K-KAT® 5218 com (marketed by KING INDUSTRIES),

[0158] - amines such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or the 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), diethyl ether-2,2'-morpholine (DMDEE), 1,4-diazabicyclo[2.2.2]octane (DABCO),

[0159] - zinc carboxylate and DBU-based catalysts (for example K-KAT® 670 marketed by KING INDUSTRIES),

[0160] - tin-based catalysts such as compounds derived from dioctyltin or di- Butyltin; in particular dioctyltin oxide, dioctyltin diacetate, dioctyl tin dilaurate, dioctyl tin dicarboxylate, dibutyl tin diacetylacetonate (DBTDAA), dibutyl tin dilaurate (DBTDL), dibutyl tin diacetate, dibutyl tin oxide, or the product of the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate, preferably the product of the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate. Examples include NEOSTANN® Sl (marketed by KANEKA), or TIB KAT® 425 or TIB KAT® 423 (marketed by TIB CHEMICALS).

[0161] Advantageously, the crosslinking catalyst is a tin-based catalyst, for example from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate.

[0162] Preferably, the crosslinking catalyst is a tin-based catalyst selected from compounds derived from dioctyltin and dibutyltin, more preferably the tin-based catalyst is obtained from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate (CAS No. 93925-43-0).

[0163] 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.

[0164] Advantageously, composition (B) comprises a crosslinking catalyst. Flame retardant

[0165] Composition (A) and / or composition (B) may further comprise a flame retardant.

[0166] Preferably, the flame retardant is chosen from triarylphosphates, trialkylphosphates and mixtures thereof, more preferably from tricresyl-phosphate, cresyldiphenyl phosphate, tributylphosphate, trioctylphosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and mixtures thereof, even more preferably, cresyldiphenyl phosphate.

[0167] The flame retardant content may range from 1% to 20% by weight relative to the total weight of the composition (B), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0168] The flame retardant content may range from 1% to 20% by weight relative to the total weight of the composition (A), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0169] The flame retardant content in each of the compositions (A) and (B) may range from 1% to 20% by weight relative to the total weight of each of the compositions (A) and (B), preferably from 5% to 18% by weight, more preferably from 8% to 15% by weight.

[0170] Advantageously, composition (A) and / or composition (B) comprises a flame retardant.

[0171] Preferably, the flame retardant is in composition (B) only. Other additives

[0172] The two-component thermally conductive 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 selected from plasticizers, solvents, UV stabilizers, and mixtures thereof.

[0173] Advantageously, the two-component thermally conductive composition according to the invention comprises a mixture of additives selected from plasticizers, solvents and UV stabilizers (or antioxidants).

[0174] Water is not considered a solvent within the meaning of the invention.

[0175] The total additive content may range from 0.1% to 10% by weight relative to the weight total of the two-component thermally conductive composition, preferably from 1% to 5% in weight, more preferably 2% to 3% by weight.

[0176] Advantageously, the two-component thermally conductive composition according to the invention comprises an additive selected from plasticizers.

[0177] By "an additive selected from the 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 include a rheology agent (r2), or a second plasticizer other than plasticizer (b) in composition (A) when composition (A) includes a rheology agent (r2).

[0178] Preferably, the additive chosen from among the plasticizers is introduced into the composition (B).

[0179] The additive chosen from among the plasticizers can be any plasticizer commonly used in the field of adhesive compositions.

[0180] Preferably, this plasticizer is chosen from:

[0181] - diisodecyl phthalate (for example PALATINOL® DIDP marketed by BASF),

[0182] - diisononyl phthalate (DINP) (for example PALATINOL® N marketed by BASF),

[0183] - an ester of alkylsulfonic acid and phenol (for example MESAMOLL® marketed by LANXESS),

[0184] - diisononyl hexahydrophthalate (for example HEXAMOLL DINCH® com marketed by BASF), and

[0185] - pentaerythritol tetravalerate (for example PEVALEN™ marketed by PERSTORP).

[0186] More preferably, this plasticizer is diisononyl hexahydrophthalate (CAS No.: 166412-78-8).

[0187] According to a preferred embodiment, the content of the additive chosen from the plasticizers ranges from 1% to 15% by weight relative to the total weight of the composition (B), preferably from 2% to 10% by weight, more preferably from 3% to 7% by weight.

[0188] The two-component thermally conductive 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 volatile at room temperature (temperature of approximately 23°C). The volatile solvent may, for example, be chosen from alcohols volatile at room temperature, such as ethanol or isopropanol. Preferably, the two-component thermally conductive 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.

[0189] Advantageously, the two-component thermally conductive composition according to the invention comprises up to 1% by weight of one or more UV stabilizers (or antioxidants) per relative to the total weight of said composition, preferably up to 0.5% by weight. UV stabilizers are typically introduced to protect the composition from degradation resulting from a reaction with oxygen that may be formed by the action of heat or light. These compounds may include antioxidants capable of scavenging free radicals.

[0190] Advantageously, the UV stabilizer(s) (or antioxidant(s)) are selected from among benzotriazoles, benzophenones, so-called hindered amines such as bis(l-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(l,2,2,6,6-pentamethyl-4-piperidyl)sebacate (CAS No. 41556-26-7), methyl l,2,2,6,6-pentamethyl-4-piperidyl sebacate (CAS No. 82919-37-7), octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, the 4,4'-bis(a,a-dimethylbenzyl)diphenylamine, and mixtures thereof. Examples include IRGANOX 1076, TINUVIN® 292, TINUVIN® 765 or TINUVIN® 770 DF marketed by BASF, RIASORB UV-123 marketed by RIANLON and OKABEST CLX 50 marketed by OKA.

[0191] Preferably, the UV stabilizer(s) (or antioxidants) are chosen from among so-called hindered amines such as bis(l-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.

[0192] More preferably, the UV stabilizers (or antioxidants) are a mixture of bis(l-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, 3-(3,5-di-tert-butyl-4-hydroxyphenyl)octadecyl propionate and 4,4'-bis(a,a-dimethylbenzyl)diphenylamine.

[0193] Advantageously, the two-component thermally conductive composition according to the invention does not include a moisture absorber, in particular selected from vinyltrimethoxysilane, vinyltriethoxysilane, alkoxyarylsilanes and p-toluenesulfonyl isocyanate.

[0194] Other characteristics of the two-component thermally conductive composition according to the invention

[0195] Advantageously, 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.

[0196] Advantageously, composition (B) does not include water.

[0197] By "does not include water" is meant a composition in which the presence The water content is solely due to the presence of moisture in the ingredients of the composition (no added water).

[0198] 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.

[0199] The moisture content of the composition (B) can be determined by summing the moisture content contributed by each of its constituent ingredients. Preferably, only the filler (C) has a significant moisture content, i.e., at least 0.05% by weight relative to the total weight of the filler (C). Thus, the moisture content of the composition (B) preferably corresponds to the moisture content contributed by the filler (C).

[0200] According to one embodiment, the two-component thermally conductive composition according to the invention comprises: - 3% to 40% by weight of silylated polymer in composition (A), relative to the total weight of composition (A), - from 0.2% to 15% by weight of rheology agent (rl) and / or (r2) in composition (A), preferably (r2), relative to the total weight of composition (A), - from 1% to 25% by weight of filler (C) in composition (B), relative to the total weight of composition (B), the filler (C) contributing between 0.0025% and 1% by weight of moisture relative to the total weight of composition (B), - from 50% to 90% by weight of thermally conductive filler(s) in each of the compositions (A) and (B), relative to the total weight of each of the 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), - from 0.01% to 1.5% by weight of crosslinking catalyst in composition (B), relative to the total weight of composition (B), - 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 - 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 two-component thermally conductive composition,

[0201] the volume ratio of composition (A) to composition (B) being between 0.25 and 4.

[0202] Preferably, the two-component thermally conductive composition according to the invention consists essentially of the ingredients mentioned above. By "consists essentially of" means that the two-component thermally conductive 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, and even more preferably less than 1% by weight.

[0203] The ingredients of this embodiment and their particular contents are as described above, including the embodiments.

[0204] According to a particular embodiment, the two-component thermally conductive composition according to the invention comprises: - 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'), - 1% to 5% by weight of rheology agent (r2) in composition (A), relative to the total weight of composition (A), the rheology agent (r2) including: • 5 to 30 wt% of a bis-urea (a) obtained by reaction of an n-alkylamine (a1) comprising 1 to 22 carbon atoms with a du-socyanate (a2) of formula (V) in which R6 is the divalent radical derived from 4,2'-MDI or 4,4'-MDI, relative to the total wt of said rheology agent (r2), and • 70 to 90% by weight of a plasticizer (b) selected from diisodecyl phthalate, di(2-propylheptyl) phthalate and mixtures thereof, relative to the total weight of said rheology agent (r2), from 6% to 11% by weight of filler (C) contributing between 0.015% and 0.1% by weight of moisture in composition (B), the percentages by weight being relative to the total weight of composition (B), the filler (C) being chosen from carbonate 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, 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), 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), 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 culation being a tin-based catalyst, - 8% to 15% by weight of flame retardant in composition (B), relative to the total weight of composition (B), the flame retardant being selected from tricresyl phosphate, cresyldiphenyl phosphate, tributyl phosphate, trioctyl phosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and mixtures thereof, and - 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 two-component thermally conductive composition,

[0205] the volume ratio of composition (A) to composition (B) being between 0.8 and 1.2.

[0206] Preferably, the two-component thermally conductive composition according to the invention consists essentially of the ingredients mentioned above.

[0207] The ingredients of this embodiment and their particular contents are as described above, including the embodiments.

[0208] 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 of compositions (A) and (B) occurs rapidly.

[0209] This reactivity can be determined by measuring the open time of the thermally conductive two-component composition according to the invention.

[0210] By "open time" is meant the time between the start of mixing of 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) he / she wishes to assemble.

[0211] Preferably, the open time of the two-component thermally conductive composition according to the invention is less than 30 minutes, more preferably less than or equal to 15 minutes.

[0212] The open time is preferably determined as described in Example 1 below.

[0213] Advantageously, the viscosity at 21 °C of the two-component thermally conductive composition according to the invention is less than or equal to 300,000 cP, preferably between 100,000 cP and 280,000 cP.

[0214] Advantageously, the viscosity at 21°C of the two-component thermally conductive composition according to the invention is determined immediately after its preparation at 20 rpm (revolutions per minute) and using a Brookfield RVT viscometer and a size 7 needle.

[0215] Preparation of the two-component thermally conductive composition according to the invention

[0216] 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.

[0217] By "under 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.

[0218] Advantageously, the two-component thermally conductive composition according to the invention is prepared without the addition of free water, that is to say, other than that inherently included in the ingredients of the composition.

[0219] According to a preferred embodiment, composition (A) is prepared according to the following process: 1) The silylated polymer is mixed, in a suitable container, with any adhesion promoter and / or flame retardant and with any 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) any thermally conductive filler(s) are dispersed in the previous mixture at the same pressure, until a homogeneous mixture is obtained, then 3) The rheology agent is added at the same pressure and the medium is homogenized.

[0220] According to a preferred embodiment, composition (B) is prepared according to the following process: 1) The optional 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 2) the charge (C) and any thermally conductive charge(s) are dispersed in the previous mixture at the same pressure, until a homogeneous mixture is obtained, then 3) the optional crosslinking catalyst is added at the same pressure and the medium is homogenized.

[0221] 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.

[0222] An example of the preparation of compositions (A) and (B) and of the two-component thermally conductive composition according to the invention is described in Example 3.

[0223] Compositions (A) and (B) can be packaged, for example, in a two-cartridge container. The distribution of the thermally conductive two-component composition is This is advantageously achieved 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 gun. Other objects of the present invention

[0224] 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.

[0225] 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, more particularly for assemblies intended for the manufacture of batteries, in particular rechargeable batteries for electric or hybrid cars.

[0226] The present invention also relates to the use of the thermally conductive two-component composition according to the invention to improve the lifespan of a battery, preferably a rechargeable battery.

[0227] 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 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).

[0228] By "free water" is meant water added to the two-component composition other than that inherently included in the ingredients of said composition.

[0229] The filler (C), the composition (A), the composition (B) and the silylated polymer are advantageously as defined above, including embodiments. In particular, the filler (C) preferably has a moisture content of between 0.1% and 3% by weight, more preferably between 0.10% and 2%, relative to the total weight of the filler (C).

[0230] Advantageously, the two-component composition is a thermally conductive two-component composition as described above.

[0231] Advantageously, the charge (C) is used for the rapid crosslinking of a two-component composition, that is to say, the use of the charge (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.

[0232] The open time is as defined above.

[0233] The present invention also relates to an article, in particular a battery, comprising the thermally conductive two-component composition according to the invention.

[0234] Preferably, the article according to the invention is a battery, in particular a rechargeable battery, more preferably for an electric or hybrid car.

[0235] Finally, the present invention relates to a method for assembling two substrates by bonding, comprising:

[0236] - coating on at least one of the two substrates to be assembled with the bi- composition thermally conductive component according to the invention, then

[0237] - the effective contacting of the two substrates.

[0238] The substrates concerned are very varied and include, 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 paint-coated composites (as in the automotive field, for example). Preferably, the substrates are metals and / or plastics.

[0239] All the embodiments described above can be combined with each other. In particular, the various aforementioned ingredients of the two-component thermally conductive composition according to the invention, and especially the preferred embodiments, can be combined with each other.

[0240] The following examples are given purely for illustrative purposes of the invention and should not be interpreted as limiting its scope. Examples Example 1: Ingredients and measurement methods Ingredients used

[0241] The following ingredients were used:

[0242] - MS POLYMER™ SAX 520 marketed by KANEKA: poly(oxide of propylene) with trimethosilane terminations of number-average molar mass between 29000 and 31000 g / mol, and a viscosity of 46 Pa.s;

[0243] - DYNASYLAN® AMMO marketed by EVONIK: (3-aminopropyl)trimethoxysilane (CAS No.: 13822-56-5), adhesion promoter;

[0244] - CALOFORT® SV14 marketed by Specialty Minerals: calcium carbonate fatty acid coated precipitate, 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);

[0245] - RIASORB UV-123 marketed by RIANLON: bis(l-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate (CAS No.: 129757-67-1), hindered amine light stabilizer (HALS);

[0246] - 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);

[0247] - NEOSTANN Sl marketed by KANEKA: product resulting from the reaction of bis(acetyloxy)dioctylstannane with tetraethyl orthosilicate (CAS No.: 93925-43-0), crosslinking catalyst;

[0248] - Hexamoll® DINCH marketed by BASF: diisononyl hexahydrophthalate, plasticizer;

[0249] - n-butylamine, primary aliphatic amine used for the preparation of the agent rheology (r2);

[0250] - diisodecyl phthalate (DIDP), plasticizer (b) used for the preparation of the agent rheology (r2);

[0251] - 4,4'-diphenylmethane diisocyanate (4,4'-MDI), diisocyanate used for pre preparation of the rheology agent (r2);

[0252] - Disflamoll® DPK marketed by LANXESS: cresyldiphenyl phosphate (CDP), flame retardant;

[0253] - Siliporite® SA 1720 marketed by ARKEMA: synthetic zeolite 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);

[0254] - SILATHERME® 1466-126 and SILATHERME® 1466-506 marketed by The Minerals Engineers: aluminosilicates with a d50 particle size of 21 µm and 9 µm respectively, thermally conductive fillers. Measurement methods

[0255] The moisture content of each load (C) (CALOFORT® SV 14 and Siliporite® SA 1720) is determined using an 870 KF Titrino plus titrator and an 803 TI stand stirring module, according to the Karl Fisher method as follows.

[0256] 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 verified using a calibration solution containing 1 mg of water per g of calibration solution (HYDRANAL™ -CRM Water Standard 1.0 marketed by Honeywell), using the "titer Ipol" program of the titrator.

[0257] 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 traces of water in approximately 50 mL of dry methanol (HYDRANAL™ - Methanol dry marketed by Honeywell) are neutralized by the titrant in the stirring module's vessel. Next, a known mass (approximately 1 g) of feed (C) is introduced into the vessel, and the exact mass introduced is entered into the program. Stirring is then continued until the medium is homogeneous (approximately 1 to 10 min). Finally, the titration is carried out automatically and the moisture content of the load (C) is displayed on the titrator screen.

[0258] Tensile strength and elongation at break were measured in accordance with ISO 37 (2005), at a constant speed of 500 mm / min.

[0259] In particular, the following conditions were applied:

[0260] A standard dumbbell-shaped test specimen, 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.

[0261] 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).

[0262] The principle of the measurement consists of stretching a standard test specimen in a tensile testing machine, the movable jaw of which moves at a constant speed of 500 mm / minute, and recording:

[0263] - the elongation at break (expressed in %) is the elongation of the specimen cor responding to the stretching observed at the time of rupture, and

[0264] - the tensile strength (in MPa) is the tensile stress at which occurs the rupture of the test tube.

[0265] The measurement is repeated for 5 test tubes, and the corresponding average of the results obtained is calculated.

[0266] The open time is determined as corresponding to the skin formation time. For this purpose, a bead of sealant (approximately 10 cm long and approximately 1 cm in diameter) is first deposited on a cardboard support. Then, using a low-density polyethylene (LDPE) pipette tip, the surface of the sealant is touched every minute for a maximum of 2 hours, in order 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).

[0267] The viscosity is determined immediately after obtaining the two-component thermally conductive composition at 20 rpm (revolutions per minute) and at 21 °C using a Brookfield RVT viscometer and a size 7 needle.

[0268] Thermal conductivity is measured in accordance with ASTM D5470.

[0269] Flammability rating is determined in accordance with UL 94.

[0270] Example 2: Preparation of the rheology agent (r2)

[0271] Two solutions are prepared:

[0272] - 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 based on the total weight of solution A, then

[0273] - 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.

[0274] 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 manufacturing.

[0275] At the reactor outlet, a stable dispersion of 23.3% by weight (relative to the total weight of the dispersion) of a bis-urea of ​​formula is obtained in the DIDP: nC4H9—HN-C--NH--(Cy)—IlC^

[0276] The Brookfield viscosity of the suspension measured at 23°C is 15 Pa.s.

[0277] Example 3: Composition 1 according to the invention comprising a composition IA and a composition IB

[0278] In a stirred reactor, the various ingredients of each of compositions IA and IB are mixed in the proportions indicated in Tables 1 and 2 below, respectively, in several stages according to the process described below. The reactor is at ambient temperature (approximately 23°C) before the ingredients are added, 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 IB.

[0279] The ingredients of step 1 are mixed under vacuum (between 60 kPa and 80 kPa) and at a sufficient stirring speed to homogenize.

[0280] Next, the ingredients from step 2 are slowly added to the reactor used for step 1, still under vacuum and at a sufficient stirring speed to homogenize.

[0281] Finally, the ingredients from step 3 are added to the reactor, still under vacuum and at a sufficient stirring speed to homogenize.

[0282] [Tables 1] Step Ingredient % by weight of total composition weight IA 1 MS POLYMER™ SAX 520 19.5 TINUVIN 770 DF 0.2 RIASORB UV-123 0.5 DYNASYLAN® AMMO 0.8 2 SILATHERME® 1466-506 38 SILATHERME® 1466-126 38 3 Rheology agent (r2) of Example 2 3

[0283] [Tables2] Step Ingredient % by weight of total composition weight IB 1 Hexamoll® DINCH 4.6 Disflamoll® DPK 11.0 2 SILATHERME® 1466-506 37.1 SILATHERME® 1466-126 37.1 CALOFORT® SV14 9.8 3 NEOSTANN Sl 0.4

[0284] The moisture content supplied by the filler (C) (CALOFORT® SV 14) is 0.02% by weight relative to the total weight of composition IB.

[0285] Composition 1 according to the invention is then obtained by introducing compositions IA and IB into a twin cartridge (protected from air and moisture), and then mixing them using a dynamic mixer attached to the nozzle of the twin cartridge, at room temperature (23°C) in a volume ratio of 1.0.

[0286] Example 4: Composition 2 according to the invention comprising a composition 2A and a composition 2B

[0287] In a reactor maintained under stirring, the different ingredients of each of the compositions 2A and 2B are mixed in the proportions indicated respectively in Tables 3 and 4 below, in several steps according to the process described in Example 3.

[0288] [Tables3] Step Ingredient % by weight of total composition weight 2A 1 MS POLYMER™ SAX 520 19.2 DYNASYLAN® AMMO 0.8 2 SILATHERME® 1466-506 38.5 SILATHERME® 1466-126 38.5 3 Rheology agent (r2) of Example 2 3.0

[0289] [Tables4] Step Ingredient % by weight of total composition weight 2B 1 Hexamoll® DINCH 4.7 Disflamoll® DPK 11.5 2 SILATHERME® 1466-506 37.9 SILATHERME® 1466-126 37.9 Siliporite® SA 1720 7.8 3 NEOSTANN Sl 0.2

[0290] The moisture content supplied by the filler (C) (Siliporite® SA 1720) is 0.08% by weight relative to the total weight of composition 2B.

[0291] Composition 2 according to the invention is then obtained by introducing compositions 2A and 2B into a twin cartridge (protected from air and moisture), and then mixing them using a dynamic mixer attached to the tip of the twin cartridge, at room temperature (23°C) in a volume ratio of 1.0.

[0292] Example 5: Mechanical properties of compositions 1 and 2 according to the invention

[0293] The mechanical properties of compositions 1 and 2 according to the invention (measured in accordance with Example 1) are summarized in Table 5 below.

[0294] [Tables5] Composition 1 (invention) 2 (invention) Open time (min) 4 10 Viscosity at 20 rpm (cP) <300000 <300000 Elongation at break (%) 80 60 Tensile strength (MPa) 1.2 1.2 Thermal conductivity (W / mK) 1.4 1.5 Flammability index V-0 V-0

[0295] 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 rapidly, while the moisture content supplied by the filler (C) is very low.

[0296] 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.

[0297] Finally, the viscosity of compositions 1 and 2 allows for easy application with a manual twin cartridge, without the need for a pneumatic gun.

Claims

Demands

1. Two-component thermally conductive composition comprising: - a composition (A) comprising: • a silylated polymer, and • a rheology agent (rl) selected from amide waxes and / or • 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 • 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, the 3,3'- [methylenebis(oxymethylene)]bis [heptane], dioctyl carbonate and their mixtures, 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 - 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) contributing at least 0.0025% by weight of moisture relative to the total weight of the composition (B), composition (A) and / or composition (B) further comprising at least one thermally conductive filler.

2. A 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): -Si(R4)p(OR5)3p (I) in which: - R4 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p equals 2, the R4 radicals are either identical or different. - R5 represents a linear or branched alkyl radical comprising 1 to 4 carbon atoms, and when p is equal to 0 or 1, the R5 radicals are identical or different, two OR5 groups being able to be involved in the same ring, 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): i 4 5 a—yOR in which: PD (IV) R4, R5 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, R1 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, R3 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-, -NR7- or -S-, R7 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 (II'), (II”), (III') or (IV'): <R°Oh JR'Vsi-R—MH-C—O—RH-O—C—HH-R—NH-G—O—fAa—C—NH-R—SKR*WOR.\ _ p II X U II J" Il OQOO (he') (R^WR^Si- R- NB- C—O- R24o- R^OC- NH- R ™ SjïR4WOR5'h., -..... ' II -Jn H OO (H”) (R5O>vp(R%Si- R5— O- R2-[p- Sî(R%(OR?hp (III') (IV') in which: R1, R3, R4, R5, X, R7 and p have the same meaning as in formulas (II), (III) and (IV), R2 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 70,000 g / mol, more preferably between 1,000 g / mol and 60,000 g / mol, even more preferably between 2000 g / mol and 50,000 g / mol.

5. A 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 reacting an n-alkylamine (a1) comprising from 1 to 22 carbon atoms, preferably n-butylamine, with a diisocyanate (a2) of formula (V): NCO-R6-NCO(V), wherein R6 is selected from one of the following divalent radicals, the formulas of which below show the two 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: CH, and - 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: - (vü) 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. Thermally conductive two-component composition according to any one of claims 1 to 7, wherein at least one thermally conductive filler is selected from aluminosilicates, alumina, aluminum hydroxide, 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. A 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 triaryl phosphates, trialkyl phosphates and mixtures thereof, more preferably from tricresyl phosphate, cresyl diphenyl phosphate, tributyl phosphate, trioctyl phosphate, tris(2-ethylhexyl)phosphate, tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate, tris(dibromopropyl)phosphate and their mixtures, even more preferentially, cresyldiphenyl phosphate.

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