Hot melt adhesive composition

Abstract

The invention relates to a hot melt adhesive composition comprising: i) at least one specific aliphatic semi-crystalline copolyamide, ii) from 3 to 35% by weight relative to the total weight of the composition at least one thermally conductive filler, the carbon atom content of which is between 80 and 100% relative to the number of atoms constituting the filler, the composition comprising less than 20% of its components having a density greater than 3. The invention also relates to its preparation process and its use.

Description

Title of the invention: Hot melt adhesive composition

[0001] The present invention relates to a hot melt adhesive composition for the encapsulation of electronic devices, a method for preparing such a composition and its use.

[0002] It is known to use polyamides as hot-melt adhesives to encapsulate electronic or mechanical devices used, for example, in the automotive or medical fields. Indeed, plastic materials are commonly used to protect batteries, whether in a car or on a smaller scale, such as a mobile phone casing. More specifically, the substrates to be encapsulated can be metals, such as copper, or polymers, such as printed circuit board materials.

[0003] Furthermore, these materials must be electrically insulating to prevent any short circuits. They must also be thermally conductive to allow, for example, a battery, if that is the element to be encapsulated, to dissipate the heat it generates during use.

[0004] In terms of implementation, encapsulating parts requires low pressure to avoid damaging the part being molded. Encapsulation is a delicate process. The material used to encapsulate the part is melted. It is then carefully deposited while hot onto the element to be encapsulated. The pressure at the nozzle exit of the molten material is described as low pressure. The term "wetting" is used to define this encapsulation. Indeed, if the nozzle exit pressure is higher, the force applied to the part being molded during the deposition of the molten material can damage the part. Several low-pressure injection processes are known for encapsulating parts. The process called "epoxy potting" has the disadvantage of being relatively long, leading to low productivity due to the relatively slow reaction time. The chemical vapor deposition process is used in the field of encapsulation.However, this process is known to be dangerous.

[0005] Thus, new materials are sought that meet both specific physico-chemical properties and allow for an easier low-pressure encapsulation process.

[0006] It turns out that, during the implementation of the encapsulation process, the materials are in a molten state, generally in a melting pot, for a relatively long period. It has been observed that known compositions undergo phase segregation. This loss of homogeneity over time results in a There is a difference in properties between the encapsulated product manufactured at the beginning of production, using homogeneous material, and the encapsulated product manufactured at the end of production, using inhomogeneous material. Furthermore, the sedimentation of fillers, making the molten material too dense, tends to clog the outlet nozzles. Over time, these relatively abrasive fillers then damage the manufacturing equipment.

[0007] There is therefore a real need to provide hot melt adhesive compositions, exhibiting good electrically insulating and thermally conductive properties, exhibiting stability over time in the molten state, and which can be easily implemented at low pressure. Summary of the invention

[0008] The invention relates to a hot-melt adhesive composition comprising: (i) at least one aliphatic semi-crystalline copolyamide comprising at least two motifs conforming to the following formula (1): X / Y (1) -The X motif is a semi-crystalline motif obtained by the polycondensation of a motif chosen from an alpha,omega-aminocarboxylic acid in C6 to C18, a lactam in C6 to C18 and a unit (diamine in Ca).(diacid in Cb), with a representing the number of carbon atoms of the diamine and b representing the number of carbons of the diacid, a being between 2 and 18 and b being between 4 and 18, the diamine in Ca and the diacid in Cb being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, -The Y motif is a motif obtained by the polycondensation of a unit (Cd diamine).(Ce diacid), with d representing the number of carbon atoms of the diamine and e representing the number of carbon atoms of the diacid, d and e being between 2 and 48, the Cd diamine and the Ce diacid being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, the Cd diamine being a polyetheramine, the Y motif having a Tg less than 30 °C, advantageously less than 20 °C, very advantageously less than 0 °C, the copolyamide having a molten viscosity measured according to ASTM D3236-88 (2009) between 0.5 and 300 Pa.s at 200°C, the copolyamide constituting the matrix of the composition, and ii) from 3 to 35% by weight relative to the total weight of the composition of at least one thermally conductive filler, the carbon atom content of which is between 80 and 100% relative to the number of atoms constituting the filler, the composition comprising less than 20% of its components having a density greater than 3.

[0009] The invention also relates to a method for preparing the composition according to the invention.

[0010] The invention finally relates to the use of the composition to encapsulate electronic devices. Detailed description

[0011] The invention is now described in more detail and in a non-limiting manner in the following description.

[0012] For the purposes of this invention, "thermofusible" means the ability of the composition to melt under the effect of heat.

[0013] Throughout the description, unless otherwise indicated, all percentages stated are molar percentages.

[0014] By the expression "between ... and...", it is understood in the context of the present invention that the limits are included in the range described. Copolyamide

[0015] The copolyamide present in the composition according to the invention is semi-crystalline and aliphatic.

[0016] The term "semi-crystalline copolyamide" covers copolyamides that have both a glass transition temperature Tg and a melting temperature Tf. Tg and Tf can be determined respectively according to ISO 11357-2:2013 and 11357-3:2013.

[0017] The nomenclature used to define polyamides is described in ISO 1874-1:1992 "Plastics - Polyamide (PA) materials for molding and extrusion - Part 1: Designation", particularly on page 3 (Tables 1 and 2), and is well known to those skilled in the art. In the PAL notation, PA designates polyamide and L designates the number of carbon atoms of the amino acid or lactam. Thus, the polyamide is obtained by the polycondensation of the amino acid or lactam containing L carbon atoms. In the PAMN notation, M designates the number of carbon atoms of the diamine and N designates the number of carbon atoms of the diacid.

[0018] It comprises at least two motifs conforming to the following formula (1): X / Y (1) in which -The X motif is a semi-crystalline motif obtained by the polycondensation of a motif chosen from an alpha,omega-aminocarboxylic acid in C6 to C18, a lactam in C6 to C18 and a unit (diamine in Ca).(diacid in Cb), with a representing the number of carbon atoms of the diamine and b representing the number of carbons of the diacid, a being between 2 and 18 and b being between 4 and 18, the diamine in Ca and the diacid in Cb being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, -The Y motif is a motif obtained by the polycondensation of a unit (Cd diamine).(Ce diacid), with d representing the number of carbon atoms of the diamine and e representing the number of carbon atoms of the diacid, d and e being between 2 and 48, the Cd diamine and the Ce diacid being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, the Cd diamine being a polyetheramine, the Y motif having a Tg less than 30 °C, advantageously less than 20 °C, very advantageously less than 0 °C, the copolyamide having a melt viscosity measured according to ASTM D3236-88 (2009) of between 0.5 and 300 Pa.s at 200°C the copolyamide forming the matrix of the composition.

[0019] Advantageously, the polyamide of formula (1) has a ratio: number of carbon atoms to number of nitrogen atoms, denoted C / N, greater than or equal to 8.

[0020] For the purposes of this invention, a semi-crystalline motif is understood to mean a polyamide which has a melting temperature (Tf) in DSC according to ISO 11357-3:2013, and an enthalpy of crystallization during the cooling step at a rate of 5K / min in DSC measured according to ISO 11357-3:2013 greater than 15 J / g, preferably greater than 30 J / g.

[0021] The motif X can result from the polycondensation of one or more alpha,omega-aminocarboxylic acids at C6 to C12. Preferably, the alpha,omega-aminocarboxylic acid is chosen from amino-7-heptanoic acid, amino-11-undecanoic acid and amino-12-dodecanoic acid.

[0022] The motif X can result from the polycondensation of one or more lactams at C6 to C12. Preferably, the lactam is chosen from caprolactam, oenantholactam and lauryllactam.

[0023] The motif X can result from the polycondensation of a unit (diamine in Ca).(diacid in Cb), with a representing the number of carbon atoms of the diamine and b representing the number of carbons of the diacid, a being between 2 and 18 and b being between 4 and 18. More particularly, b is between 5 and 18.

[0024] The diamine in Ca can be chosen from among the aliphatic diamines, linear or branched, the cycloaliphatic diamines.

[0025] When the diamine in Ca is aliphatic and linear, of formula H2N-(CH2)a-NH2, it is preferentially chosen from ethylenediamine (a=2), butanediamine (a=4), pentanediamine (a=5), hexanediamine (a=6), heptanediamine (a=7), octanediamine (a=8), nonanediamine (a=9), decanediamine (a=10), undecanediamine (a=11), dodecanediamine (a=12), tridecanediamine (a=13), tetradecanediamine (a=14), hexadecanediamine (a=16), octadecanediamine (a=18), octadecanediamine (a=18).

[0026] When the diamine in Ca is aliphatic and branched, it may contain one or several methyl or ethyl substituents on the main chain. For example, it can advantageously be chosen from 2,2,4-trimethyl-l,6-hexanediamine, 2,4,4-trimethyl-l,6-hexanediamine, 2-methyl-l,5-pentanediamine, 2-methyl-1,8-octanediamine.

[0027] When the diamine in Ca is cycloaliphatic, it can be chosen from piperazine (a=4) denoted pip below and amino-ethylpiperazine (a=6).

[0028] Preferably, the Ca diamine is chosen from ethylene diamine, hexamethylene diamine, decanediamine and piperazine.

[0029] The Cb diacid can be chosen from among the aliphatic diacids, linear or branched, the cycloaliphatic diacids.

[0030] Throughout the description, the expressions "diacid" or "dicarboxylic acid" or "dicarboxylic acid" refer to the same product.

[0031] When the diacid in Cb is aliphatic, it can be chosen from adipic acid (b=6), heptanedioic acid (b=7), octanedioic acid (b=8), azelaic acid (b=9), sebacic acid (b=10), undecanedioic acid (b=11), dodecanedioic acid (b=12), brassylic acid (b=13), tetradecanedioic acid (b=14), hexadecanedioic acid (b=16), octadecanedioic acid (b=18), octadecenedioic acid (b=18).

[0032] When the diacid is cycloaliphatic, it may include the following carbon skeletons: norbomyl, cyclohexyl, dicyclohexyl, dicyclohexylpropane.

[0033] Preferably, motif X is selected from caprolactam, oenantholactam and lauryllactam, 7-aminoheptanoic acid, 11-aminoundecanoic acid and 12-aminododecanoic acid, PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA 56, PA 59, PA 510, PA 66, PA 69, PA 610, PA 512, PA 612, PA 514, PA 614, PA 618, PA pipl0, PA pipl2, PA 1010, PA 1012, PA 1014, PA 1018, PA 1210, PA 1212, PA 1214, the PA1218. More specifically, motif X is chosen from caprolactam, lauryllactam, amino-11-undecanoic, PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA59, PA510, PA 69, PA610, PA 512 and PA612.

[0034] Preferably, motif X is chosen from an amino acid and a lactam or PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA59, PA510, PA 66, PA 69, PA610, PA 512, PA612, more particularly, motif X is chosen from amino acids and lactams having a number of carbon atoms greater than 6. More particularly, motif X is a PA6, a PA11, a PA12, a PA 210, a PA 212, a PA 69, a PA610, or a PA612.

[0035] The motif Y is obtained by the polycondensation of one unit (diamine to Cd).(diacid to Ce), with d representing the number of carbon atoms of the diamine and e representing the number of carbon atoms of the diacid, d and e being between 2 and 48, the diamine in Cd and diacid in Ce being linear or branched aliphatic, saturated or unsaturated, the diamine in Cd being chosen from aliphatic diamines, cycloaliphatic diamines and polyetheramines.

[0036] The Cd diamine can be chosen from among the aliphatic diamines, linear or branched, the cycloaliphatic diamines, as defined above for the Ca diamines.

[0037] The diamine in Cd can also be chosen from feicosanediamine (a=20), do-cosanediamine (a=22).

[0038] The Cd diamine can also be obtained from the amination of polymerized fatty acids, as defined below. The Cd diamine can be a C36 or C44 diamine.

[0039] The diamine in Cd can also be chosen from bis(3,5-dialkyl-4-aminocyclohexyl)methane, bis(3,5-dialkyl-4-aminocyclohexyl)ethane, bis(3,5-dialkyl-4-aminocyclo-hexyl)propane, bis(3,5-dialkyl-4-aminocyclo-hexyl)butane, bis-(3-methyl-4-aminocyclohexyl)-methane (BMACM or MACM), p-bis(aminocyclohexyl)-methane (PACM) and isopropylidenedi(cyclohexylamine) (PACP), isophoronediamine (f=10), piperazine (f=4) hereafter referred to as pip, ramino-ethylpiperazine. It may also contain the following carbon skeletons: norbomyl methane, cyclohexylmethane, dicyclohexylpropane, di(methylcyclohexyl), di(methylcyclohexyl)propane. A non-exhaustive list of these cycloaliphatic diamines is given in the publication "Cycloaliphatic Amines" (Encyclopaedia of Chemical Technology, Kirk-Othmer, 4th Edition (1992), pp. 386-405).

[0040] The diamine in Cd can also be a polyetheramine, that is, a polyoxyalkylene diamine. Preferably, it is a polyoxyalkylene chain bearing an amine group at the end of the chain. The polyoxyalkylene chain preferably comprises oxyethylene (POE), oxypropylene (POP), or oxytetramethylene (POTM) groups, alone or in mixture. When the groups are in mixture, mixtures of POE and POP or POTM and POP are preferred.

[0041] These compounds can be obtained by cyanoacetylation of aliphatic α,co-dihydroxylated polyoxyalkylene called polyetherdiols. The polyetheramine is preferably chosen from commercially available products, in particular those sold by Huntsman under the brands Jeffamine® and Elastamine® (for example Jeffamine® D400, D2000, ED 2003, XTJ 542, Elastamine® RT 1000, RP 405, RP 2009) or under the brand Baxxodur® by BASF (for example Baxxodur® EC 302, EC 301; EC 303, EC 311).

[0042] Preferably, the number-average molecular mass of polyetheramine is between 60 and 2000 g.mol*, more particularly between 80 and 1500 g.mol*, and even more preferably between 100 and 500 g.mol*.

[0043] The Cd diamine can also be obtained from the amination of polymerized fatty acids, as defined below. These diamines are commercially available under the brand name "Versamine®" sold by Cognis Corporation (BASF) and under the trade name Priamine® from Croda.

[0044] The diacid in Ce can be chosen from among the aliphatic diacids, linear or branched, the cycloaliphatic diacids, as defined above for the diacids in Cb.

[0045] The diacid in Ce can also be chosen from eicosanedioic acid (b=20), docosanedioic acid (b=22) and fatty acid dimers.

[0046] The diacid in C36 can be derived from polymerized fatty acids. These polymerized fatty acids refer to compounds produced from coupling reactions of unsaturated fatty acids, which lead to mixtures of products bearing two acidic functions (called acid dimers) or three acidic functions (called acid trimers). This coupling can be a combination or condensation reaction of 2 moles of an unsaturated monocarboxylic acid, the monoacids being either identical or different. This dimerization reaction can be carried out using catalytic or non-catalytic polymerization methods according to known techniques. For example, the dimeric diacid in C36 can be obtained by dimerization of an unsaturated monoacid in C18, such as oleic acid, linoleic acid, linolenic acid, and mixtures thereof. These mixtures are present, for example, in tallol.Generally, these mixtures consist mainly of the dimer, and in smaller quantities of the monomer, trimer, and oligomers. After separation, fatty acid dimers are obtained predominantly, from 75% to over 98%, in mixtures with, in particular, the monomer, the "1 and 1 / 2 mother," and the corresponding trimer.

[0047] Dimeric diacids can be obtained from C14 myristoleic acid, C16 palmitoleic acid, C16 sapienic acid, C18 oleic acid, C18 elaidic acid, C18 trans-vaccenic acid, C18 linoleic acid, C18 linoleaidic acid, C18 alpha-linolenic acid, C18 gamma-linolenic acid, C20 11-eicosenoic acid, C20 eicosapentaenoic acid, C20 dihomo-gamma-linolenic acid, C20 arachidonic acid, C22 erucic acid, C22 clupanodonic acid, C22 docosahexaenoic acid, of nervonic acid in 24 and their mixture.

[0048] Polymerized fatty acids are commercially available and in particular the product with the trade name Pripol® marketed by the company Croda can be used as well as the product with the trade name Empol® marketed by the company Cognis or the product with the trade name Unydime® marketed by the company Kraton or the product with the trade name Radiacid® marketed by the company Oleon.

[0049] Fatty acid dimers can then be transformed into amino dimers, by transformation of both acid functions into amine functions, or into amino acid dimers, by transformation of one of the acid functions into an amine function.

[0050] Preferably, the diacids used for motif Y are acid dimers, and more particularly C36 and C44 dimers are used.

[0051] Preferably, motif Y is chosen from PA 236, PA 536, PA 636, PA 1036, PA pip36, PA pip44, PA 244, PA 544, PA 644, PA 1044, PA POP36, PA POP44, PA POP6, PA POP9, PA POP10, PA POP12, PA POP14, POP being a polyetheramine with a molar mass between 60 and 2000 g / mol.

[0052] The Y motif of the copolyamide according to the invention preferably has a Tg of less than 30 °C, advantageously less than 0 °C. The glass transition temperature can be determined by differential scanning calorimetry (DSC) according to ISO 11357-2:2013, Plastics - Differential Scanning Calorimetry (DSC) Part 2. The heating and cooling rates are 20 °C / min.

[0053] The copolyamide according to the invention comprises from 30 to 99.5 mole percent of motif X and from 0.5 to 70 mole percent of motif Y, preferably from 40 to 98 mole percent of motif X and from 2 to 60 mole percent of motif Y, and more particularly from 50 to 90 mole percent of motif X and from 10 to 50 mole percent of motif Y.

[0054] The molar percentages of motifs X and Y are measured by calculating the percentage of the number of moles of monomers constituting motif X, for example, relative to the sum of the number of moles of all the monomers constituting the copolyamide, i.e., X and Y, excluding the chain limiter: the excess diamine or diacid is not included. The following formula illustrates the calculation: [Form 1]

[0055] %mol = n (monomers of motif X) * 100 12 nfnomers of co-polyamide)

[0056] The copolyamide according to the invention has a melt viscosity measured according to ASTM D3236-88 (2009) of between 0.5 and 300 Pa·s at 200°C, preferably from 0.5 to 200 Pa·s, even more preferably from 1 to 100 Pa·s at 200°C, and more particularly from 2 to 30 Pa·s at 200°C. More particularly, the melt viscosity is measured using a Brookfield rheometer with the SC module 4-27 according to ASTM D3236-88 (2009) at 200 °C.

[0057] The copolyamide according to the invention preferably has a Tg of less than 20 °C, advantageously less than 0 °C. The glass transition temperature can be determined by differential scanning calorimetry (DSC) according to ISO 11357-2:2013, Plastics - Differential Scanning Calorimetry (DSC) Part 2. The speeds of heating and cooling are 20°C / min.

[0058] Preferably, the copolyamide according to the invention comprises at least one of the motifs selected from PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA 56, PA 59, PA 510, PA 512, PA66, PA 69, PA 610, PA 612, PA6, PAU, PA 12, PA1010, PA 1012, PA 1212, PA piplO, PA pip36, PA pip44, PA POP40036, PA POP40044, PA POP40010, PA POP4006, PA POP200036, PA POP200044, PA POP200010, PA POP20006, PA3636, PA3644, PA 4436, PA 4444 and their mixture.

[0059] Preferably, the copolyamide according to the invention is selected from the following structures: PA 26 / pip36, PA 210 / pip36, PA 212 / pip36, PA 214 / pip36, PA 218 / pip36, PA 59 / pip36, PA 510 / pip36, PA 512 / pip36, PA 610 / pip36, PA 612 / pip36, PA6 / pip36, PA1010 / pip36, PA 1012 / pip36, PA 1212 / pip36, PA 26 / pip44, PA 210 / pip44, PA 212 / pip44, PA 214 / pip44, PA 218 / pip44, PA 59 / pip44, PA 510 / pip44, PA 512 / pip44, PA 610 / pip44, PA 612 / pip44, PA6 / pip44, PA1010 / pip44, PA 1012 / pip44, PA 1212 / pip44, PA 26 / POP40036, PA 210 / POP40036, PA 212 / POP40036, PA 214 / POP40036, PA 218 / POP40036, PA 59 / POP40036, PA 510 / POP40036, PA 512 / POP40036, PA 610 / POP40036, PA 612 / POP40036, PA6 / POP40036, PA1010 / POP40036, PA 1012 / POP40036, PA 1212 / POP40036, PA 26 / POP40010, PA 210 / POP40010, PA 212 / POP40010, PA 214 / POP40010, PA 218 / POP40010, PA 59 / POP40010, PA 510 / POP40010, PA 512 / POP40010, PA 610 / POP40010, PA 612 / POP40010, PA6 / POP40010,PA1010 / POP40010, PA 1012 / POP40010, PA 1212 / POP40010, PA 26 / POP4006, PA 210 / POP4006, PA 212 / POP4006, PA 214 / POP4006, PA 218 / POP4006, PA 59 / POP4006, PA 510 / POP4006, PA 512 / POP4006, PA 610 / POP4006, PA 612 / POP4006, PA6 / POP4006, PA1010 / POP4006, PA 1012 / POP4006, PA 1212 / POP4006,, PA 26 / 3636, le PA 210 / 3636, the PA 212 / 3636, PA 214 / 3636, PA 218 / 3636, PA 59 / 3636, PA 510 / 3636, PA 512 / 3636, PA 610 / 3636, PA 612 / 3636, PA6 / 3636, PA 11 / 3636, PA 12 / 3636 and PA 1 l / 3636 / pip36, PA1010 / 3636, PA 1012 / 3636, PA 1212 / 3636, PA 26 / POP200036, PA 210 / POP200036, PA 212 / POP200036, PA 214 / POP200036, PA 218 / POP200036, PA 59 / POP200036, PA 510 / POP200036, PA 512 / POP200036, PA 610 / POP200036, PA 612 / POP200036, PA6 / POP200036, PA1010 / POP200036, PA 1012 / POP200036, PA 1212 / POP200036, PA 26 / pip36 / POP40036, PA 210 / pip36 / POP40036, PA 212 / pip36 / POP40036, PA 214 / pip36 / POP40036, PA 218 / pip36 / POP40036, PA 59 / pip36 / POP40036,PA 510 / pip36 / POP40036, PA 512 / pip36 / POP40036, PA 610 / pip36 / POP40036, PA 612 / pip36 / POP40036, PA6 / pip36 / POP40036, PA1010 / pip36 / POP40036, PA 1012 / pip36 / POP40036, PA 1212 / pip36 / POP40036, PA 26 / pip36 / POP200036, only PA 210 / pip36 / POP200036, only PA 212 / pip36 / POP200036, only PA 214 / pip36 / POP200036, only PA 218 / pip36 / POP200036, PA 59 / pip36 / POP200036, PA 510 / pip36 / POP200036, , PA 512 / pip36 / POP200036, PA 610 / pip36 / POP200036, PA 612 / pip36 / POP200036, PA6 / pip36 / POP200036, PA1010 / pip36 / POP200036, PA 1012 / pip36 / POP200036, PA 1212 / pip36 / POP200036, PA 26 / pip36 / POP4006, only PA 210 / pip36 / POP4006, only PA 212 / pip36 / POP4006, only PA 214 / pip36 / POP4006, only PA 218 / pip36 / POP4006, PA 59 / pip36 / POP4006, PA 510 / pip36 / POP4006, PA 512 / pip36 / POP4006, PA 610 / pip36 / POP4006, PA 612 / pip36 / POP4006, PA6 / pip36 / POP4006, PA1010 / pip36 / POP4006, PA 1012 / pip36 / POP4006, PA 1212 / pip36 / POP4006, PA 26 / pip36 / POP20006, PA only 210 / pip36 / POP20006, PA only 212 / pip36 / POP20006, PA only 214 / pip36 / POP20006, PA only 218 / pip36 / POP20006, PA 59 / pip36 / POP20006, PA 510 / pip36 / POP20006, PA 512 / pip36 / POP20006, PA 610 / pip36 / POP20006, PA 612 / pip36 / POP20006, PA6 / pip36 / POP20006, PA1010 / pip36 / POP20006, PA 1012 / pip36 / POP20006, PA 1212 / pip36 / POP20006,POP20006 means that it is a motif resulting from the condensation of a polyetheramine with the formula polyoxypropylene and a molar mass of 2000 g / mol with a C6 diacid.

[0060] In a particularly preferred manner, the copolyamide according to the invention comprises a motif X selected from a diamine-diacid unit and a motif Y comprising piperazine as a diamine in Cd and a diacid comprising more than 6 carbon atoms as a diacid in Ce.

[0061] According to another preferred embodiment, the Ce diacid is a dimer of C36 or C44 acid.

[0062] According to yet another embodiment, the copolyamide according to the invention comprises a motif X of the type (diamine in Ca).(diacid in Cb) comprising an average number of carbon atoms per nitrogen atom greater than or equal to 6 and a motif Y comprising piperazine as a diamine in Cd and a diacid comprising more than 6 carbon atoms as a diacid in Ce.

[0063] Preferably, the copolyamide according to the invention comprises, as a diacid in Ce, an acidic dimer or a polyetheramine as a diamine in Cd.

[0064] According to a preferred embodiment, the copolyamide according to the invention is selected from PA 26 / pip36, PA 210 / pip36, PA 59 / pip36, PA 510 / pip36, PA 512 / pip36, PA 610 / pip36, PA 210 / POP40036, PA 59 / POP40036, PA 510 / POP40036, PA 610 / POP40036, PA 210 / POP40010, PA 59 / POP4009, PA 510 / POP40010, PA 26 / POP4006, PA 210 / POP4006, PA 610 / POP4006, PA 26 / pip36 / POP40036, PA 210 / pip36 / POP40036, PA 510 / pip36 / POP40036, PA 610 / pip36 / POP40036, PA6 / pip36 / POP40036, PA 210 / pip36 / POP200036, PA 59 / pip36 / POP200036, PA 510 / pip36 / POP200036, PA 512 / pip36 / POP200036, PA 610 / pip36 / POP200036, PA 210 / pip36 / POP20006, PA 610 / pip36 / POP20006, PA 6 / 3636, PA 11 / 3636, PA 12 / 3636 and the PA 1 l / 3636 / pip36.

[0065] According to one embodiment of the invention, the copolyamide consists of the two patterns X and Y defined above.

[0066] According to another embodiment, which is preferred, the copolyamide comprises more than two motifs X and Y as defined above. Preferably, the copolyamide included in the composition according to the invention comprises at least three different motifs. For example, the copolyamide according to the invention may comprise two motifs X and one motif Y, one motif X and two motifs Y, or two motifs X and two motifs Y. Preferably, the copolyamide included in the composition according to the invention is a ter-polyamide and a tetrapolyamide.

[0067] Preferably, the copolyamide according to the invention comprises fatty acid dimer, advantageously in a content of 1 to 35 mol%, preferably of 2 to 30 mol%, preferably of 7 to 25 mol% relative to the total number of moles of the copolyamide.

[0068] Preferably, the copolyamide according to the invention comprises a polyether diamine content of between 0.5 and 25 mol%, preferably between 1 and 22 mol%, preferably between 1.5 and 14 mol% relative to the total number of moles of the copolyamide.

[0069] The piperazine content in the copolyamide is preferably less than 40 mol%, advantageously less than 30 mol%, very advantageously less than 20 mol% relative to the total number of moles of the copolyamide. Chain limiter

[0070] The copolyamides of the invention are synthesized in a conventional manner, in the presence, if necessary, of chain limiters or chain termination agents.

[0071] Suitable chain-terminating agents to react with the amino terminal function may be monocarboxylic acids, anhydrides, such as phthalic anhydride, monohalogenated acids, monoesters or monoisocyanates.

[0072] Preferably, monocarboxylic acids are used. They can be chosen from monocarboxylic aliphatic acids, such as acetic acid, propionic acid, lactic acid, valeric acid, caproic acid, capric acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyric acid; alicyclic acids, such as cyclohexanecarboxylic acid; monocarboxylic aromatic acids, such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, γ-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid and phenylacetic acid; and mixtures thereof. The preferred compounds are aliphatic acids, including acetic acid, propionic acid, lactic acid, valeric acid, caproic acid, capric acid, lauric acid, tridecyl acid, myristic acid, palmitic acid, and stearic acid..

[0073] Among the chain-terminating agents suitable for reacting with the acid terminal function, monoamines, monoalcohols, monoiso- may be cited cyanates.

[0074] Preferably, monoamines are used. They can be chosen from aliphatic monoamines, such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, laurylamine, stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; alicyclic amines, such as cyclohexylamine and dicyclohexylamine; aromatic monoamines, such as aniline, toluidine, diphenylamine and naphthylamine; and mixtures thereof.

[0075] Preferred compounds are butylamine, hexylamine, octylamine, decylamine, laurylamine, stearylamine, cyclohexylamine and aniline.

[0076] The chain limiters can also be a dicarboxylic acid, which is introduced in excess with respect to the stoichiometry of the diamine(s); or a diamine which is introduced in excess with respect to the stoichiometry of the diacid(s).

[0077] According to a preferred embodiment, the copolyamide present in the composition according to the invention is wholly or partly a recycled copolyamide. When the polyamide is a recycled polyamide, it contains functional groups resulting from oxidation reactions selected from imide, alcohol, or carboxylic acid groups, preferably imides or alcohols, in a molar ratio relative to the amide groups higher than that of the same non-recycled polyamide.

[0078] According to one embodiment, said molar ratio of functions resulting from oxidation reactions, that is to say the sum of the number of moles of imide, acid and alcohol functions over the number of moles of amide functions of the copolyamide is between 1 / 10000 and 1 / 20.

[0079] This ratio can be measured by calculating the concentrations by proton NMR. The copolyamide sample is prepared by dissolving the copolyamide in d2-dichloromethane, adding HFIP (hexafluoroisopropanol).

[0080] In a first variant, said molar ratio of imide functions is between 1 / 1000 and 1 / 20, in particular between 1 / 500 and 1 / 20, in particular between 1 / 200 and 1 / 50.

[0081] In a second variant, said molar ratio of carboxylic acid functions is between 1 / 5000 and 1 / 20, in particular between 1 / 3000 and 1 / 50, very advantageously between 1 / 500 and 1 / 25.

[0082] In a third variant, said molar ratio of alcohol functions is between 1 / 1000 and 1 / 20 and advantageously between 1 / 1000 and 1 / 25 very advantageously between 1 / 200 and 1 / 50.

[0083] Preferably, the copolyamide present in the composition preferably has a melting temperature between 100 and 220 °C, advantageously between 120 and 200 °C, very advantageously between 130 and 180 °C.

[0084] The water content of the copolyamide after exposure to 23 °C and 50% relative humidity (measured at equilibrium) is preferably between 0.1 and 1.2% by weight, advantageously from 0.15 to 0.7% by weight relative to the total weight of the copolyamide.

[0085] The copolyamide described above constitutes the matrix of the composition according to the invention. The thermally conductive charge

[0086] The composition according to the invention comprises from 3 to 35% by weight relative to the total weight of the composition, at least one thermally conductive filler, the carbon atom content of which is between 80 and 100% relative to the number of atoms constituting the filler. Preferably, the filler comprises from 94 to 99.99% carbon atoms.

[0087] The carbon filler can be selected from natural graphites, synthetic graphites, expanded graphites, graphene, carbon blacks, and carbon fibers. Preferably, the filler is selected from natural graphites, synthetic graphites, and expanded graphites.

[0088] The graphite used in the composition according to the invention can be produced synthetically or naturally. There are three types of naturally produced graphite available commercially: flake graphite, amorphous graphite, and crystalline graphite.

[0089] Flake graphite, as its name suggests, has a flake-like morphology. Amorphous graphite is not truly amorphous as its name suggests but is in fact crystalline. Amorphous graphite is available in average sizes from about 5 micrometers to about 10 centimeters. Crystalline graphite generally has a vein-like appearance on its outer surface, hence its name. Crystalline graphite is commercially available in flake form from Asbury Graphite and Carbon Inc. Carbons.

[0090] Synthetic graphite can be produced from coke and / or pitch, which are derived from petroleum or coal. Synthetic graphite is of greater purity than natural graphite but is not as crystalline. One type of synthetic graphite is electrographite, which is produced from calcined petroleum coke and coal tar pitch in an electric furnace. Another type of synthetic graphite is produced by heating calcined petroleum pitch to 2800°C. Synthetic graphite tends to have a lower density, higher porosity, and higher electrical resistance than natural graphite.

[0091] Preferably, the thermally conductive charge has a median average particle size D50 ranging from 0.5 to 500 micrometers. Within this range, the charge particles have D50 sizes from 1 to 200 pm, preferably 20 150 pm can be used to advantage.

[0092] Preferably, the thermally conductive charge has a median average particle size D90 ranging from 1 to 400 micrometers, advantageously from 2 to 200 pm, very advantageously from 5 to 150 pm.

[0093] The values ​​of D50 and D90 can be estimated according to ISO 13320-1:1999.

[0094] In one embodiment, the thermally conductive charge, and therefore the com position does not include particles with a diameter greater than 500 pm, advantageously no particles with a diameter greater than 400 pm.

[0095] When the carbon charge is not composed of 100% carbon, the impurities are preferably chosen from the following chemical species: SiO2, Fe2O3, Al2O3, CaO, MgO, K2O, Na2O, TiO2, MnO, P2O5.

[0096] According to one embodiment, the specific surface area BET measured according to ISO 9277:2010 is between 1 and 300 m2 / g, very advantageously between 1.5 and 200 m2 / g.

[0097] Preferably, these charges have an average shape factor greater than 3, advantageously greater than 7, very advantageously greater than 15.

[0098] Scanning electron microscopy allows for the observation and visual assessment of the morphology of compounds. Morphometry, based on video acquisition and image analysis, provides access to quantifiable parameters characteristic of particle morphology. Various commercial devices are available: examples include the Malvern Morphologi G2, the Retsch Camsizer, and the Occhio Alpaga 500 Nano, described on the websites www.malvern.com, www.retsch-technology.com, and www.occhio.be.

[0099] Using the Alpaga 500 Nano apparatus, acquisitions are made for each sample tested on 10000 particles and the elongation and bluntness parameters are calculated for each particle.

[0100] The mathematical tools used for their calculation are developed in the doctoral thesis of E. Pirard (1993, University of Liège, 253 p.) entitled “Euclidean morphometry of plane figures. Applications to the analysis of granular materials”. The document, entitled “The descriptive and quantitative representation of particle shape and morphology”, is available under ISO / DIS 9276-6.

[0101] Preferably, the thermally conductive charge has a density of less than 3 kg / L, advantageously less than 2.5 kg / L, very advantageously less than 2.3 kg / L. The density is measured in accordance with ISO 787-10:1993.

[0102] Preferably, when the thermally conductive filler is expanded graphite, then it is present in the composition according to the invention at a content of between 5 and 17% by weight relative to the total weight of the composition. Preferably, the Expanded graphite is the only thermally conductive filler in the composition.

[0103] When the thermally conductive filler is not expanded graphite, then it is present in the composition according to the invention in a content of between 5 and 35% by weight relative to the total weight of the composition. Additives

[0104] The composition according to the invention may include at least one additive.

[0105] The additive can be selected from a catalyst, an antioxidant, a thermal stabilizer, a UV stabilizer, a light stabilizer, a lubricant, a flame retardant, a nucleating agent, a chain extender and a colorant.

[0106] Advantageously, the above-defined composition further comprises additives selected from antioxidants, UV stabilizers, thermal stabilizers, plasticizers, nucleating agents, sticking agents, shock modifiers, flame retardants, antistatic agents, reinforcing agents, lubricants, organic and inorganic fillers, optical brighteners, release agents, pigments, dyes, catalysts and mixtures thereof.

[0107] The composition may comprise between 0 and 10% by weight of additives relative to the total weight of the composition, preferably between 0.1 and 5% of additive.

[0108] The composition comprises less than 20%, very advantageously less than 10%, preferably less than 5% of components having a density greater than 3.

[0109] For the purposes of this invention, a component is defined as any product present in the composition according to the invention, regardless of its chemical nature. In other words, less than 20% of the fillers and additives that may be present in the composition need have a density greater than 3.

[0110] According to a particular embodiment of the invention, the composition consists of the copolyamide as defined above as a matrix, 3 to 35% by weight relative to the total weight of the composition of at least one thermally conductive filler, the carbon atom content of which is between 80 and 100%, and 0 to 10% by weight of additives relative to the total weight of the composition, the composition comprising less than 20% of components having a density greater than 3 (measured according to ISO 787-10:1993).

[0111] The molten viscosity of the composition is preferably between 0.5 and 400 Pa.s, advantageously between 2 and 200 Pa.s, and very advantageously between 3 and 100 Pa.s. The molten viscosity is measured using a Brookfield rheometer with module SC 4-27 according to ASTM D3236-88 (2009) at 210°C.

[0112] Preferably, the composition according to the invention thus has a surface resistivity greater than 1010 Q.m, preferably greater than 1011 Qm, measured according to IEC 62631-3-2 (2015). In other words, the composition is electrically insulating.

[0113] The composition according to the invention preferably has an elongation at break (during ISO 527 tensile tests at 23 °C) greater than 10%, advantageously greater than 30%.

[0114] The tensile modulus at 23°C of the composition measured on IA specimen (ISO 527) is preferably between 100 and 5000 MPa, advantageously between 200 and 4000 MPa, very advantageously between 200 and 800 MPa.

[0115] The composition preferably has a dielectric constant (Dk) measured at 1 GHz preferably between 2 and 6, advantageously from 2.5 to 4 and a dissipation factor (tan ô) between 0.001 and 0.1, advantageously between 0.005 and 0.05.

[0116] The dielectric constant and dissipation factor are measured according to ASTM D150 on a 100*100*2 mm plate at a frequency of 1 GHz.

[0117] The composition according to the invention has a thermal conductivity between 0.9 W / mK and 4 W / mK, advantageously from 1 W / mK to 3 W / mK, measured according to ASTM D5930-17.

[0118] The invention also relates to the encapsulation process using the composition according to the invention.

[0119] The composition according to the invention is used to manufacture molded parts by low-pressure injection molding. This injection molding cycle may include the following different steps: a) The mold is closed after the parts to be glued have been inserted. b) the molten composition according to the invention is injected into the mold up to a pressure of between 0.5 and 50 bars and optionally subjected to a holding pressure, c) The molding composition is allowed to solidify by cooling. d) the mold is open, e) the injection molded parts are removed from the mold.

[0120] The low pressure injection molding process generally operates in the range of 2 to 40 bars, with the temperature between 160 and 250° C.

[0121] Thus, the composition according to the invention is suitable for injection at low pressure, that is to say at a pressure less than 100 bars, preferably less than 50 bars. Use

[0122] According to yet another aspect, the present invention relates to the use of the composition according to the invention as defined above for the encapsulation of electronic devices, also called overmolding or molding, preferably located under the hood of a vehicle or in medical devices.

[0123] The present invention also relates to the use of the composition according to the invention as defined above for the manufacture of a hot melt adhesive in the form of a veil, a film, granules, a filament, a grid or a powder.

[0124] The molten viscosity of the composition is between 0.5 and 400 Pa.s, advantageously between 2 and 200 Pa.s, very advantageously between 3 and 100 Pa.s. The molten viscosity is measured using a Brookfield rheometer with module SC 4-27 according to ASTM D3236-88 (2009) at 210°C with a powder.

[0125] The invention is illustrated by the figure and the following examples, which are in no way limiting. Examples

[0126] L Preparation of compositions and measurements

[0127] The compositions were obtained by mixing in the molten state the components described in Tables 1 and 2 below.

[0128] All the above compositions were manufactured using a ZSK 18 mm twin-screw extruder (Coperion). The barrel temperature was set at 210°C and the screw speed was 280 rpm with a throughput of 8 kg / h. The compositions were then dried under reduced pressure at 80°C to achieve a moisture content of less than 0.04%.

[0129] IA test pieces (according to ISO 527) and 5 mm plates were manufactured by injection molding using a Battenfeld® BA800 CDC press with unpolished molds. The following parameters were applied during injection: - Sheath temperature: 120°C. - Nozzle temperature: 150°C. - Mold temperature: 15°C. - Cycle time: 60 seconds.

[0130] [Tables 1] 1 Inv 2 Inv 3 Inv 4 Inv % mass % mass % mass % mass Polyamide 1 92 90 85 85 Expanded graphite 2 8 10 15 - Graphite 3 - - - 15 Resistivity (Ωm) >10» >10» >10» >10» Conductivity X (W / mK) 0.542 0.609 0.929 0.626 Sedimentation no no no no

[0131] In Table 1 above: 1 Polyamide refers to a hot melt adhesive polyamide composed of 31 mol% diacid in C10, 19% pripol® 1013, 25 mol% piperazine, 6.6 mol% Jeffamine® D 2000 and 18.4 mol% ethylene diamine. 2 Expanded graphite refers to graphite with the trade name Timrex® C Therm HD max with a density of less than 2.5 sold by Imerys 3 Graphite refers to the Timrex® M100 trade name graphite with a density of less than 2.5 sold by Imerys

[0132] [Tables2] 5 Inv 6 Inv 7 Comp 8 Comp % mass % mass % mass % mass Polyamide 1 75 65 60 59.5 Graphite 3 25 35 40 - Expanded graphite 2 - - - 1 Aluminum oxide 4 - - - 32 Boron nitride 5 - - - 7.5 Resistivity (Ωm) >10⁻¹² 4.10⁶ ND X-ray conductivity (W / mK) 0.857 1.250 ND ND Sedimentation no no no yes

[0133] In Table 2 above: 1 Polyamide refers to a hot melt adhesive polyamide composed of 31 mol% diacid in C10, 19% pripol® 1013, 25 mol% piperazine, 6.6 mol% Jeffamine® D 2000 and 18.4 mol% ethylene diamine. 3 Graphite refers to graphite with the trade name Timrex® M100 and a density of less than 2.5 sold by Imerys 2 Expanded graphite is sold under the name C Therm® HD max with a density of less than 2.5, sold by Imerys 4. Aluminum oxide is sold under the name Martoxid® TM 4250 with a density greater than 3, sold by Martinswerk 5 Boron nitride is sold by Henze under the name 19-E-01-HF-02 with a density of 2.3.

[0134] In these examples, the thermal and electrical properties of these compositions were measured according to the following methods. The homogeneity of these compositions in the molten state was also evaluated.

[0135] Thermal conductivity

[0136] Thermal conductivity was measured at 23°C on 100*100*5 mm plates using the Neotim® FP2C machine equipped with a hot wire in accordance with ASTM D5930-17.

[0137] Resistivity

[0138] Measurements according to IEC 62631-3-2 (2015) were carried out on the Sefelec® M1500P equipped with cell 8009, under the following conditions: - Potential difference: 40V - Charging time before reading: 60 seconds - Plate thickness: 100*100*5mm

[0139] Homogeneity and Sedimentation

[0140] Granules of the compositions are placed in a test tube immersed in a silicone oil bath at 15°C above the melting point (Tf) of the copolyamide for 30 minutes. After 30 minutes, the tube is placed at room temperature until the composition solidifies. The tube is then broken open to recover the composition.

[0141] If sedimentation is significant, an accumulation of charges can be observed at the bottom of the tube.

[0142] If this is not the case, the sample is cut in two (upper part separated from the lower part of the tube) in order to estimate the densities at 23°C according to ISO 1182-1 of the upper and lower parts of the sample. If the difference in density is greater than 0.3, the sedimentation is considered too significant.

[0143] 2, Conclusions

[0144] The results show that the composition according to the invention allows for the encapsulation of parts at low pressure using a melting pot. The composition according to the invention exhibits good thermal conductivity, preventing overheating of electronic equipment, while also being electrically insulating, thus preventing short circuits.

Claims

Claims

1. Hot-melt adhesive composition comprising: i) at least one aliphatic semi-crystalline copolyamide comprising at least two units corresponding to the following formula (1): X / Y (1) in which -the unit X is a semi-crystalline unit obtained by the polycondensation of a unit chosen from a C6 to C18 alpha, omega-aminocarboxylic acid, a C6 to C18 lactam and a (Ca diamine) (Cb diacid) unit, with a representing the number of carbon atoms of the diamine and b representing the number of carbon atoms of the diacid, a being between 2 and 18 and b being between 4 and 18, the Ca diamine and the Cb diacid being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, -the unit Y is a unit obtained by the polycondensation of a (Cd diamine) unit.(Ce diacid), with d representing the number of carbon atoms of the diamine and e representing the number of carbon atoms of the diacid, d and e being between 2 and 48, the Cd diamine and the Ce diacid being linear or branched aliphatic, cycloaliphatic, saturated or unsaturated, the Cd diamine possibly being a polyether amine, the Y unit having a Tg of less than 30°C, advantageously less than 20°C, very advantageously less than 0°C, the copolyamide having a viscosity in the molten state measured according to standard ASTM D3236-88 (2009) of between 0.5 and 300 Pa.s at 200°C, the copolyamide constituting the matrix of the composition, ii) from 3 to 35% by weight relative to the total weight of the composition at least one thermally conductive filler, the carbon atom content of which is between 80 and 100% relative to the number of atoms constituting the charge, the composition comprising less than 20% of its components having a density greater than 3.

2. Composition according to claim 1, characterized in that the thermally conductive filler is chosen from natural graphites, synthetic graphites, expanded graphites, graphenes, carbon blacks, and carbon fibers.

3. Composition according to claim 1 or 2, characterized in that the thermally conductive filler has a median average particle size D50 ranging from 0.5 to 500 micrometers.

4. Composition according to any one of the preceding claims, characterized in that the thermally conductive filler has a median average particle size D90 ranging from 1 to 400 micrometers.

5. Composition according to any one of the preceding claims, characterized in that the thermally conductive filler has an average form factor greater than 3.

6. Composition according to any one of the preceding claims, characterized in that it comprises less than 10%, preferably less than 5% of its components having a density greater than 3.

7. Composition according to any one of the preceding claims, characterized in that the copolyamide comprises a crystalline X unit chosen from caprolactam, oenantholactam and lauryllactam, amino-7-heptanoic acid, amino-11-undecanoic acid and amino-12-dodecanoic acid, PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA 56, PA59, PA510, PA 66, PA 69, PA610, PA 512, PA612, PA 514, PA614, PA618, PA piplO, PA pipl2, PA1010, PA1012, PA1014, PA1018, PA1210, PA1212, PA1214, PA1218.

8. Composition according to any one of the preceding claims, characterized in that the copolyamide comprises a Y unit chosen from PA 236, PA 536, PA 636, PA 1036, PA pip36, PA pip44, PA 244, PA 544, PA 644, PA 1044, PA POP36, PA POP44, PA POP6, PA POP9, PA POP10, PA POP12, PA POP14, POP being a polyetheramine with a molar mass of between 60 and 2000 g / mol.

9. Composition according to any one of the preceding claims, characterized in that the copolyamide comprises at least one of the units chosen from PA 26, PA 29, PA 210, PA 212, PA 214, PA 218, PA 56, PA 59, PA 510, PA 512, PA66, PA 69, PA 610, PA 612, PA6, PAU, PA 12, PA1010, PA 1012, PA 1212, PA pip10, PA pip36, PA pip44, PA POP40036, PA POP40044, PA POP40010, PA POP4006, PA POP200036, PA POP200044, PA POP200010, PA POP20006, PA3636, PA3644, PA 4436, PA 4444 and their mixture.

10. Composition according to any one of the preceding claims, characterized in that the copolyamide is chosen from PA 6 / 3636, PA 11 / 3636, PA 12 / 3636 and PA 11 / 3636 / pip36.

11. Composition according to any one of the preceding claims, characterized in that it has a viscosity in the molten state ranging from 0.5 to 400 Pa.s, preferably from 2 to 200 Pa.s at 200°C, and more particularly from 3 to 100 Pa.s at 210°C.

12. Composition according to any one of the preceding claims, characterized in that it comprises expanded graphite in a content of between 5 and 17% by weight relative to the total weight of the composition, as the only thermally conductive filler of the composition.

13. Composition according to any one of the preceding claims, characterized in that it has a surface resistivity greater than 1010Q.m, preferably greater than 1011 Qm, measured according to standard IEC 62631-3-2 (2015).

14. Composition according to any one of the preceding claims, characterized in that it has a thermal conductivity of between 0.9 W / mK and 4 W / mK, advantageously from 1 W / mK to 3 W / mK, measured according to standard ASTM D5930-17.

15. Composition according to any one of the preceding claims, characterized in that it comprises additives chosen from antioxidants, UV stabilizers, heat stabilizers, plasticizers, nucleating agents, tackifiers, impact modifiers, flame retardants, antistatic agents, reinforcing agents, lubricants, organic and inorganic fillers, optical brighteners, mold release agents, pigments, dyes, catalysts and mixtures thereof.

16. Composition according to any one of the preceding claims, characterized in that it is capable of being injected at a pressure of less than 100 bars, preferably less than 50 bars.

17. Use of the composition as defined in any one of the preceding claims for the encapsulation of electronic devices, preferably located under the engine hood of a vehicle or in medical devices.