Antistatic or dust-repellent poly(methyl methacrylate) compositions

Abstract

The present invention relates to a poly(methyl methacrylate) composition and its use, which comprises 85 to 98 wt. % of poly(methyl methacrylate) having a loss factor tan δ of at least 10, relative to the weight of the composition, and 2 to 15 wt. % of a copolymer comprising polyamide blocks and polyether blocks, relative to the weight of the composition.

Description

[Technical Field]

[0001] The present invention also relates to compositions based on poly(methyl methacrylate) and to uses of the compositions. [Background technology]

[0002] It is known that electrostatic charges form and are retained on most plastic surfaces. In the case of poly(methyl methacrylate) (PMMA), static charges formed on PMMA granules, especially during transportation, can cause the granules to stick together (making them difficult to separate) and then form blocks, which can make unloading the granules problematic, for example. The presence of static charges on transparent PMMA objects can cause dust to accumulate on these objects, thus hindering their use and damaging their aesthetic appearance. In industry, residual PMMA powder also tends to adhere to machined parts. Dust accumulation on the surfaces of these objects can alter their transparency.

[0003] Antistatic agents such as ethoxylated amine or sulfonate-type ionic surfactants added to polymers have been described in the prior art. However, the antistatic properties of the polymer depend on ambient humidity, and these agents are not permanent because they migrate to the surface of the polymer and disappear. Subsequently, hydrophilic copolymers containing polyamide blocks and polyether blocks have been proposed as antistatic agents. These agents have the advantage of not migrating and therefore providing permanent antistatic properties that are further independent of ambient humidity.

[0004] EP 2984137 relates to a transparent antistatic poly(methyl methacrylate) (PMMA) composition comprising 55% to 99.9% by weight of PMMA relative to the total weight of the composition and 0.1% to 45% by weight of at least one PEBA copolymer containing a polyamide PA block and a polyether PE block comprising polyethylene glycol (PEG), the copolymer being characterized in that it contains 50% to 80% by weight of PEG relative to the total weight of the copolymer.

[0005] There is a need to provide compositions based on poly(methyl methacrylate) that simultaneously have good antistatic or antidust properties, as well as good mechanical properties and good transparency. Summary of the Invention

[0006] The present invention provides, firstly, - 85% to 98% by weight, based on the weight of the composition, of poly(methyl methacrylate), which has a loss factor tanδ, which is the ratio of the moduli of elasticity G'' and G', measured at a temperature of 220°C and an angular frequency of 1 rad / s, of greater than or equal to 10; - a copolymer containing polyamide blocks and polyether blocks in an amount ranging from 2% to 15% by weight relative to the weight of the composition; The present invention relates to a composition comprising:

[0007] The present invention satisfies the above-mentioned needs, and more particularly provides a composition based on poly(methyl methacrylate) that simultaneously has good antistatic or antidust properties, as well as good mechanical properties and good transparency.

[0008] This is achieved by combining poly(methyl methacrylate) in a content of 85% to 98% by weight relative to the weight of the composition with at least one copolymer containing polyamide blocks and polyether blocks in a content of 2% to 15% by weight relative to the total weight of the composition, the poly(methyl methacrylate) having melt viscoelastic properties characterized by a loss factor tan δ of greater than or equal to 10. More specifically, it has been found that such compositions have both good antistatic or dust-proof properties and good mechanical properties (impact strength, Vicat point, etc.), especially compared to compositions consisting of PMMA or compositions having a loss factor tan δ outside the claimed range. DETAILED DESCRIPTION OF THE INVENTION

[0009] The invention will now be explained in more detail, in a non-limiting manner, in the following description.

[0010] The composition according to the invention is preferably a transparent composition.

[0011] The term "transparent composition" means a composition having a transmittance of at least 88% according to the ASTM D1003-97 / ISO13468 standard and a haze (turbidity or cloudiness) of less than 15%, preferably less than 10%, preferably less than 5% according to the ASTM D 1003-97 standard, these two properties being measured at 560 nm on a 2 mm thick plate.

[0012] The term "antistatic composition" means a composition having a surface resistivity of 10, as measured according to the ASTM D 257 standard. 12 ohm / m 2 Less than and 10 9 ohm / m 2 means a composition that is super

[0013] The term "dust-proofing composition" means a composition having a surface resistivity of 10, as measured according to the ASTM D 257 standard. 12 ohm / m 2 Super 10 13 ohm / m 2 "composition" means a composition that is less than

[0014] composition The transparent composition according to the present invention comprises poly(methyl methacrylate) (PMMA).

[0015] The term "PMMA" refers to methyl methacrylate (MMA) homopolymer or copolymer or mixtures thereof.

[0016] The PMMA is present in the transparent composition in a content ranging from 85 wt % to 98 wt % relative to the weight of the composition. For example, the PMMA may be present in the composition in a content of 85 wt % to 88 wt %, or 88 wt % to 90 wt %, or 90 wt % to 92 wt %, or 92 wt % to 94 wt %, or 94 wt % to 96 wt %, or 96 wt % to 98 wt % relative to the weight of the composition.

[0017] According to a particular embodiment, the PMMA comprises an MMA copolymer.

[0018] According to other embodiments, the PMMA is a mixture of at least one homopolymer and at least one copolymer of MMA, or a mixture of at least two copolymers of MMA with different average molar masses, or a mixture of at least two copolymers of MMA with different monomer compositions.

[0019] The MMA copolymer may comprise 60% to 99.7% by weight of methyl methacrylate and 0.3% to 40% by weight of at least one monomer containing at least one ethylenic unsaturation copolymerizable with methyl methacrylate. Preferably, the MMA copolymer may comprise 70% to 99%, advantageously 90% to 95%, more advantageously 70% to 90%, preferably 80% to 90%, or 85% to 90% by weight of methyl methacrylate and 1% to 30%, advantageously 5% to 30%, more advantageously 10% to 30% by weight of at least one monomer containing at least one ethylenic unsaturation copolymerizable with methyl methacrylate.

[0020] Preferably, the monomer containing at least one ethylenic unsaturation copolymerizable with methyl methacrylate is a (meth)acrylic monomer. The (meth)acrylic monomer is selected from acrylic acid, methacrylic acid, alkyl acrylic monomers, alkyl methacrylic monomers, and mixtures thereof. Preferably, the monomer is selected from acrylic acid, methacrylic acid, alkyl acrylic monomers, alkyl methacrylic monomers, and mixtures thereof, wherein the alkyl group contains 1 to 22 carbon atoms and is linear, branched, or cyclic, and the alkyl group preferably contains 1 to 12 carbon atoms and is linear, branched, or cyclic. More preferably, the (meth)acrylic monomer is selected from ethyl methacrylate, methyl acrylate, ethyl acrylate, methacrylic acid, acrylic acid, n-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, isobutyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, and isobornyl methacrylate, and mixtures thereof.

[0021] Advantageously, the (meth)acrylic monomer is chosen from alkyl (meth)acrylates in which the alkyl group contains 1 to 12 carbon atoms. Examples include methyl acrylate and ethyl, butyl or 2-ethylhexyl (meth)acrylate. Preferably, the comonomer is an alkyl acrylate in which the alkyl group contains 1 to 4 carbon atoms.

[0022] More advantageously, the (meth)acrylic monomers are chosen from methyl methacrylate, methyl acrylate and ethyl acrylate, and / or mixtures thereof.

[0023] The PMMA contained in the composition according to the present invention may have a weight average molecular weight of 70,000 g / mol to 160,000 g / mol, preferably 70,000 to 100,000 g / mol.

[0024] The weight average molecular weight is measured by size exclusion chromatography using PMMA as a calibration standard. The PMMA polymer is dissolved in hexafluoroisopropanol stabilized with 0.05 M potassium trifluoroacetate at a concentration of 1 g / L, then passed through a modified silica column at a flow rate of, for example, 1 mL / min, and the mass is measured by refractive index.

[0025] Furthermore, the PMMA contained in the composition according to the present invention has melt viscoelastic properties characterized by a loss factor tanδ of 10 or more, preferably 11 or more, more preferably 12 or more, and even more preferably 15 or more. The PMMA may in particular have a loss factor tanδ of 10 to 15, or 15 to 20, or 20 to 25, or 25 to 30, or 30 to 35, or 35 to 40, or even more than 40. The loss factor tanδ is the ratio of the elastic moduli G'' and G' measured at a temperature of 220°C and an angular frequency of 1 rad / s. The elastic modulus G', called the "storage modulus," characterizes the elastic behavior of a material (the energy stored and fully recovered by the material). The elastic modulus G'', called the "loss or dissipation modulus," characterizes the viscous behavior of a material (the energy dissipated in the form of heat). These rheological properties are measured using a parallel-plate oscillatory rheometer according to the ISO 6721-10:2015 standard.

[0026] The composition according to the invention also comprises at least one copolymer containing polyamide blocks and polyether blocks.

[0027] Copolymers containing polyether blocks and polyamide blocks (abbreviated as "PEBA") result from the polycondensation of polyamide blocks having reactive ends with polyether blocks having reactive ends, in particular 1) a polyamide block having a diamine chain end and a polyoxyalkylene block having a dicarboxylic acid chain end; 2) polyamide blocks with dicarboxylic acid chain ends and polyoxyalkylene blocks with diamine chain ends, obtained, for example, by cyanoethylation and hydrogenation of α,ω-dihydroxylated aliphatic polyoxyalkylene blocks known as polyether diols; 3) Polyamide blocks and polyether diols with dicarboxylic acid chain ends and the resulting product is, in this particular case, a polyetheresteramide.

[0028] Polyamide blocks with dicarboxylic acid chain ends result, for example, from the condensation of polyamide precursors in the presence of a chain-limiting dicarboxylic acid. Polyamide blocks with diamine chain ends result, for example, from the condensation of polyamide precursors in the presence of a chain-limiting diamine.

[0029] The polymer having polyamide blocks and polyether blocks may also contain randomly distributed units.

[0030] Three types of polyamide blocks can be used to advantage.

[0031] According to the first type, the polyamide blocks result from the condensation of dicarboxylic acids, in particular those containing from 4 to 20 carbon atoms, preferably those containing from 6 to 18 carbon atoms, and aliphatic or aromatic diamines, in particular those containing from 2 to 20 carbon atoms, preferably those containing from 6 to 14 carbon atoms.

[0032] Examples of dicarboxylic acids include 1,4-cyclohexanedicarboxylic acid, butanedioic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, terephthalic acid, and isophthalic acid, but also dimerized fatty acids.

[0033] Examples of diamines may include tetramethylenediamine, hexamethylenediamine, 1,10-decamethylenediamine, dodecamethylenediamine, trimethylhexamethylenediamine, isomers of bis(4-aminocyclohexyl)methane (BACM), bis(3-methyl-4-aminocyclohexyl)methane (BMACM), 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP), para-aminodicyclohexylmethane (PACM), isophoronediamine (IPDA), 2,6-bis(aminomethyl)norbornane (BAMN), and piperazine (Pip).

[0034] Advantageously, PA 4.12, PA 4.14, PA 4.18, PA 6.10, PA 6.12, PA 6.14, PA 6.18, PA 9.12, PA 10.10, PA 10.12, PA 10.14 and PA 10.18 blocks are used. In the notation PAX.Y, X, as in the past, represents the number of carbon atoms derived from the diamine residue, and Y represents the number of carbon atoms derived from the diacid residue.

[0035] According to the second type, the polyamide blocks result from the condensation of one or more α,ω-aminocarboxylic acids and / or one or more lactams containing 6 to 12 carbon atoms in the presence of dicarboxylic acids or diamines containing 4 to 12 carbon atoms. Examples of lactams include caprolactam, oenantholactam, and lauryllactam. Examples of α,ω-aminocarboxylic acids include aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid.

[0036] Advantageously, the second type of polyamide block is made of polyamide 11, polyamide 12 or polyamide 6. In the notation PA X, X represents the number of carbon atoms from the amino acid residue.

[0037] According to a third type, the polyamide blocks result from the condensation of at least one α,ω-aminocarboxylic acid (or lactam), at least one diamine and at least one dicarboxylic acid.

[0038] In this case, the polyamide PA block is - a linear aliphatic or aromatic diamine containing X carbon atoms; - a dicarboxylic acid containing Y carbon atoms; and - a comonomer {Z} selected from lactams and α,ω-aminocarboxylic acids containing Z carbon atoms, and an equimolar mixture of at least one diamine containing X carbon atoms and at least one dicarboxylic acid containing Y carbon atoms, wherein (X1, Y1) are different from (X, Y). comonomer {Z}, which is introduced in a weight proportion ranging up to 50%, preferably up to 20%, and even more advantageously up to 10%, relative to the total amount of polyamide precursor monomers; By polycondensation of - in the presence of a chain limiting agent selected from dicarboxylic acids A dicarboxylic acid containing Y carbon atoms is prepared and used as a chain limiter, advantageously introduced in excess relative to the stoichiometry of the diamine.

[0039] According to one variant of this third type, the polyamide blocks result from the condensation of at least two α,ω-aminocarboxylic acids, or at least two lactams containing 6 to 12 carbon atoms, or one lactam with one aminocarboxylic acid having no carbon atoms, in the presence of an optional chain-limiting agent. Examples of aliphatic α,ω-aminocarboxylic acids include aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Examples of lactams include caprolactam, oenantholactam, and lauryllactam. Examples of aliphatic diamines include hexamethylenediamine, dodecamethylenediamine, and trimethylhexamethylenediamine. Examples of alicyclic diacids include 1,4-cyclohexanedicarboxylic acid. Examples of aliphatic diacids include butanedioic acid, adipic acid, azelaic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, dimerized fatty acids (these dimerized fatty acids preferably have a dimer content of at least 98%, are preferably hydrogenated, and are sold by Unichema under the brand name "Pripol" or by Henkel under the brand name "Empol"), and α,ω-diacid polyoxyalkylenes. Examples of aromatic diacids include terephthalic acid (T) and isophthalic acid (I). Examples of alicyclic diamines include bis(4-aminocyclohexyl)methane (BACM), bis(3-methyl-4-aminocyclohexyl)methane (BMACM), and 2,2-bis(3-methyl-4-aminocyclohexyl)propane (BMACP), as well as isomers of para-aminodicyclohexylmethane (PACM). Other commonly used diamines can be isophoronediamine (IPDA), 2,6-bis(aminomethyl)norbornane (BAMN), and piperazine.

[0040] As examples of polyamide blocks of the third type, mention may be made of: PA 6.6 / 6 (wherein 6.6 represents a hexamethylenediamine unit condensed with adipic acid and 6 represents a unit resulting from the condensation of caprolactam); -PA 6.6 / 6.10 / 11 / 12 (wherein 6.6 represents hexamethylenediamine condensed with adipic acid, 6.10 represents hexamethylenediamine condensed with sebacic acid, 11 represents units resulting from the condensation of aminoundecanoic acid, and 12 represents units resulting from the condensation of lauryllactam).

[0041] The designations PA X / Y, PA X / Y / Z, etc. relate to copolyamides where X, Y, Z, etc. represent homopolyamide units as defined above.

[0042] Advantageously, at least one polyamide block of the copolymer used in the composition of the invention is selected from the group consisting of the following polyamide monomers: 6, 11, 12, 5.4, 5.9, 5.10, 5.12, 5.13, 5.14, 5.16, 5.18, 5.36, 6.4, 6.9, 6.10, 6.12, 6.13, 6.14, 6.16, 6.18, 6.36, 10.4, 10.9, 10.10, 10.12, 10.13, 10 .14, 10.16, 10.18, 10.36, 10.T, 12.4, 12.9, 12.10, 12.12, 12.13, 12.14, 12.16, 12.18, 12.36, 12.T and mixtures or copolymers thereof, preferably selected from the following polyamide monomers: 6, 11, 12, 6.10, 10.10, 10.12 and mixtures or copolymers thereof.

[0043] Preferably, the polyamide blocks comprise at least 30% by weight, preferably at least 50% by weight, preferably at least 75% by weight, preferably 100% by weight, of PA 11 or PA 12 relative to the total weight of the polyamide blocks.

[0044] The polyether blocks may represent 50% to 80% by weight of the copolymer having polyamide blocks and polyether blocks.

[0045] The polyether blocks may in particular be blocks derived from PEG (polyethylene glycol), i.e., blocks composed of ethylene oxide units, and / or blocks derived from PPG (propylene glycol), i.e., blocks composed of propylene oxide units, and / or blocks derived from PO3G (polytrimethylene glycol), i.e., blocks composed of polytrimethylene glycol ether units, and / or blocks derived from PTMG, i.e., blocks composed of tetramethylene glycol units, also known as polytetrahydrofuran. PEBA copolymers may contain several types of polyethers in their chains, and the copolyethers may be in block or statistical form.

[0046] In the context of the present invention, it is preferred that the PEBA copolymer comprises PEG blocks optionally combined with PPG, PO3G and / or PTMG blocks.

[0047] Thus, according to certain embodiments, the PEBA copolymer comprises PEG blocks. These blocks may be present in the PEBA copolymer in a content of 50% to 80% by weight, preferably 55% to 75% by weight, and even more preferably 60% to 70% by weight, relative to the weight of the copolymer. For example, this content may be 50% to 55% by weight, or 55% to 60% by weight, or 60% to 65% by weight, or 65% to 70% by weight, or 70% to 75% by weight, or 75% to 80% by weight, relative to the weight of the copolymer.

[0048] Advantageously, the copolymer of the composition also comprises at least one polyether other than PEG chosen from polypropyl glycol (PPG), polytrimethylene glycol (PO3G), polytetramethylene glycol (PTMG) and mixtures thereof.

[0049] It is also possible to use blocks obtained by oxyethylation of bisphenols, such as bisphenol A. The latter products are described in EP 613919.

[0050] The polyether blocks may comprise ethoxylated primary amines. Examples of ethoxylated primary amines include those of the formula: Mention may be made of the products of formula TIFF0007792347000001.tif39170, in which m and n are from 1 to 20 and x is from 8 to 18. These products are commercially available from Arkema under the brand name Noramox® and from Clariant under the brand name Genamin®.

[0051] The flexible polyether block may comprise a polyoxyalkylene block having an NH chain end, and such a block can be obtained by cyanoacetylation of an α,ω-dihydroxylated aliphatic polyoxyalkylene block, called a polyether diol. More specifically, Jeffamine products (e.g., Jeffamine® D400, D2000, ED2003, XTJ542, which are commercial products of Huntsman, and are also described in patents JP2004346274, JP2004352794, and EP1482011) can be used.

[0052] The polyether diol blocks are used in unmodified form and copolycondensed with polyamide blocks having carboxylic acid end groups, or they are aminated to convert them into polyether diamines and then condensed with polyamide blocks having carboxylic acid end groups. A general method for the two-step preparation of PEBA copolymers containing ester linkages between the PA and PE blocks is known and is described, for example, in French Patent No. 2846332. A general method for preparing the PEBA copolymers of the present invention containing amide linkages between the PA and PE blocks is known and is described, for example, in European Patent EP1482011. It is also possible to prepare polymers containing polyamide blocks and polyether blocks with randomly distributed units by mixing the polyether blocks with polyamide precursors and chain-limiting diacids (single-step process).

[0053] It goes without saying that the designation PEBA in this specification of the present invention relates not only to Pebax® products sold by Arkema, Vestamid® products sold by Evonik® and Grilamid® products sold by EMS, but also to Pelestat® type PEBA products sold by Sanyo or any other PEBA from other suppliers.

[0054] Advantageously, the PEBA copolymer may contain polyamide blocks as PA 6, as PA 11, as PA 12, as PA 6.12, as PA 6.6 / 6, as PA 10.10 and / or as PA 6.14, preferably as PA 11 and / or PA 12 blocks, and polyether blocks as PEG.

[0055] Particularly preferred PEBA copolymers in the context of the present invention are copolymers comprising blocks from: - derived from PA 11 and PEG; - derived from PA 12 and PEG; - derived from PA 10.10 and PEG; - derived from PA 10.12 and PEG; - derived from PA 6.12 and PEG; - derived from PA 6 and PEG.

[0056] Preferably, the PEBA copolymers preferred in the context of the present invention are copolymers comprising a PA 11 or PA 12 block and a block derived from PEG.

[0057] In other words, the copolymer according to the invention may comprise at least one PEBA selected from PA 6-PEG, PA 11-PEG, PA 12-PEG, PA 10.10-PEG, PA 10.12-PEG, PA 6.12-PEG and mixtures thereof, and preferably comprises PA 11-PEG or PA 12-PEG, or even better is PA 11-PEG or PA 12-PEG.

[0058] Although the block copolymers described above generally comprise at least one polyamide block and at least one polyether block, the present invention also encompasses all copolymers comprising two, three, four (or more) different blocks selected from those described herein, provided that these blocks comprise at least polyamide and polyether blocks.

[0059] Advantageously, the copolymer alloy according to the invention comprises a block-segment copolymer comprising three different types of blocks (called "triblocks" in the present specification) resulting from the condensation of some of the above blocks, the triblocks being preferably chosen from copolyetheresteramides, copolyetheramideurethanes, with a content of: the mass percentage of polyamide blocks is greater than 10%; The mass percentage of the PEG blocks is greater than 50%.

[0060] The number average molar mass of the polyamide blocks in the PEBA copolymer is preferably 400 to 20,000 g / mol, more preferentially 500 to 10,000 g / mol, and even more preferentially 200 to 2,000 g / mol. In certain embodiments, the number average molar mass of the polyamide blocks in the PEBA copolymer is 400 to 1,000 g / mol, or 1,000 to 1,500 g / mol, or 1,500 to 2,000 g / mol, or 2,000 to 2,500 g / mol, or 2,500 to 3,000 g / mol, or 3,000 to 3,500 g / mol, or 3,500 to 4,000 g / mol, or 4,000 to 5,000 g / mol, or 5,000 to 6,000 g / mol, or 6,000 to 7,000 g / mol, or 7,000 to 8,000 g / mol, or 8000 to 9000 g / mol, or 9000 to 10000 g / mol, or 10000 to 11000 g / mol, or 11000 to 12000 g / mol, or 12000 to 13000 g / mol, or 13000 to 14000 g / mol, or 14000 to 15000 g / mol, or 15000 to 16000 g / mol, or 16000 to 17000 g / mol, or 17000 to 18000 g / mol, or 18000 to 19000 g / mol, or 19000 to 20000 g / mol.

[0061] The number average molar mass of the polyether blocks is preferably 100 to 6000 g / mol, more preferentially 200 to 3000 g / mol. In a particular embodiment, the number average molar mass of the polyether blocks is 100 to 200 g / mol, or 200 to 500 g / mol, or 500 to 800 g / mol, or 800 to 1000 g / mol, or 1000 to 1500 g / mol, or 1500 to 2000 g / mol, or 2000 to 2500 g / mol, or 2500 to 3000 g / mol, or 3000 to 3500 g / mol, or 3500 to 4000 g / mol, or 4000 to 4500 g / mol, or 4500 to 5000 g / mol, or 5000 to 5500 g / mol, or 5500 to 6000 g / mol.

[0062] The number average molar mass is determined by the content of chain limiter, which can be calculated according to the following formula: M n =n モノマー ×MW 反復単位 / n 鎖制限剤 +MW 鎖制限剤

[0063] In this formula, n モノマー represents the number of moles of monomer, and n 鎖制限剤 represents the molar excess of limiting agent (e.g., diacid), and MW 反復単位 represents the molar mass of the repeating unit, and MW 鎖制限剤 represents the excess molar mass of the limiting agent (e.g., diacid).

[0064] The number-average molar masses of the polyamide blocks and the polyether blocks can be determined by gel permeation chromatography (GPC) before copolymerization of the blocks.

[0065] The weight ratio of polyamide blocks to polyether blocks of the PEBA copolymer may in particular be from 0.1 to 20. This weight ratio can be calculated by dividing the number average molar mass of the polyamide blocks by the number average molar mass of the polyether blocks.

[0066] Thus, the weight ratio of polyamide blocks to polyether blocks in the PEBA copolymer can be 0.1 to 0.2; or 0.2 to 0.3; or 0.3 to 0.4; or 0.4 to 0.5; or 0.5 to 1; or 1 to 2; or 2 to 3; or 3 to 4; or 4 to 5; or 5 to 7; or 7 to 10; or 10 to 13; or 13 to 16; or 16 to 19; or 19 to 20.

[0067] A range of 2 to 19, more specifically 4 to 10, is particularly preferred.

[0068] The PEBA copolymer is present in the composition in an amount ranging from 2% to 15% by weight, preferably from 5% to 15% by weight, based on the weight of the composition. For example, the PEBA copolymer may be present in the composition in an amount ranging from 2% to 3% by weight, or from 3% to 5% by weight, or from 5% to 7% by weight, or from 7% to 9% by weight, or from 9% to 10% by weight, or from 10% to 11% by weight, or from 11% to 12% by weight, or from 12% to 13% by weight, or from 13% to 14% by weight, or from 14% to 15% by weight, based on the weight of the composition.

[0069] The addition of at least one PEBA copolymer to the PMMA can be carried out by any method known to those skilled in the art of polymers, in particular by dry mixing, or by kneading at a temperature above the glass transition temperature of the various polymers added, or by shearing at a temperature substantially equal to the flow temperature of the various polymers added, in particular by calendering, by extrusion, or by mixing in solution.

[0070] Advantageously, the composition of the invention comprises 10 14 ohm / m 2 Below 10, preferably 11 ~10 14 ohm / m 2 , e.g. 10 12 ~10 13 ohm / m 2 It has dust-proof or anti-static properties with a surface resistivity of

[0071] Even more advantageously, the composition does not require or contain organic salts.

[0072] Nevertheless, it is possible to incorporate organic salts or ionic liquids into the composition according to the invention in order to further improve its dust-proofing performance.

[0073] Thus, according to a particular embodiment, the composition according to the invention may comprise, in the molten state, from 0.1% to 10% by weight, preferably from 0.1% to 5% by weight, of at least one organic salt relative to the total weight of the composition.

[0074] The term "organic salt" means a salt consisting of an organic cation associated with an inorganic or organic anion.

[0075] The at least one organic salt can be added in a molten state, i.e., when the organic salt is at a temperature higher than its melting point. Preferably, the at least one organic salt is an ionic liquid having a melting point of less than 300°C, preferably less than 200°C, preferably less than 100°C, and then advantageously preferably less than 30°C. Particular properties of ionic liquids are non-volatility (no diffusion of volatile organic compounds into the atmosphere), non-flammability (therefore, easy handling and storage), stability at high temperatures (some up to 400°C), good electrical conductivity, and high stability against water and oxygen.

[0076] The organic salt may comprise at least one cation comprising one or more of the following molecules: ammonium, sulfonium, pyridinium, pyrrolidinium, imidazolium, phosphonium, lithium, guanidinium, piperidinium, thiazolium, triazolium, oxazolium, pyrazolium, and mixtures thereof.

[0077] Furthermore, the organic salts may be selected from the group consisting of the following molecules: imides, in particular bis(trifluoromethanesulfonyl)imide (NTf - borates, especially tetrafluoroborate (BF4 - phosphates, especially hexafluorophosphate (PF6 - phosphinates and phosphonates, especially alkyl phosphonates; amides, especially dicyanamide (DCA - aluminates, especially tetrachloroaluminate (AlCl4 - ), halides (e.g., bromides, chlorides, iodides, etc.), cyanates, acetates (CH3COO - ), especially trifluoroacetate; sulfonates, especially methanesulfonate (CH3SO3 -), trifluoromethanesulfonate; sulfonate, especially ethyl sulfate, hydrogen sulfate, and mixtures thereof.

[0078] For the purposes of the present invention, the term "organic salt" means more particularly any organic salt that is stable at the temperatures used during the synthesis of the block copolymers according to the present invention. Those skilled in the art can refer to the data sheets of the organic salts, which indicate the decomposition limit temperature of each organic salt.

[0079] Examples of organic salts that can be used in the context of the present invention include, in particular, organic salts based on ammonium cations, on imidazolium or imidazolinium cations, on pyridinium cations, on dihydropyridinium cations, on tetrahydropyridinium cations, on pyrrolidinium cations, on guanidine cations, on phosphonium cations.

[0080] Organic salts based on ammonium cations include, for example: -bis(trifluoromethanesulfonyl)imide anion and N-trimethyl-N-propylammonium cation; an anion selected from bromide, tetrafluoroborate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide and an N-trimethyl-N-butylammonium or N-trimethyl-N-hexylammonium cation; - iodide, bis(trifluoromethanesulfonyl)imide or dicyanamide anion and N-tributyl-N-methylammonium cation; - tetrafluoroborate anion and tetraethylammonium cation; -dimethylphosphate anion and (2-hydroxyethyl)trimethylammonium cation; -trifluoroacetate anion and bis(2-hydroxyethyl)ammonium cation; -sulfamate anion and N,N-bis(2-methoxy)ethylammonium cation; -2-hydroxyacetate or trifluoroacetate anion and N,N-dimethyl(2-hydroxyethyl)ammonium cation; -bis(trifluoromethylsulfonyl)imide anion and N-ethyl-N,N-dimethyl-2-methoxyethylammonium cation; -ethyldimethylpropylammonium cation and bis(trifluoromethylsulfonyl)imide anion; -methyltrioctylammonium cation and bis(trifluoromethylsulfonyl)imide anion; -methyltrioctylammonium cation and trifluoroacetate or trifluoromethylsulfonate anion; -tetrabutylammonium cation and bis(trifluoromethylsulfonyl)imide anion; -tetramethylammonium cation and bis(oxalato(2-))borate or tris(pentafluoroethyl)trifluorophosphate anion Mix the above.

[0081] Mention may also be made of imidazole-based organic salts, such as di-, mono- or tri-substituted imidazoles, in particular those based on imidazolium or imidazolinium cations.

[0082] For example, an organic salt in combination with an imidazolium cation can be mentioned. -chloride anion and H-methylimidazolium cation; chloride, bromide, tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, bis(trifluoromethanesulfonyl)imide, tetrachloroaluminate, ethylphosphonate or methylphosphonate, methanesulfonate, ethylsulfate or ethylsulfonate anions with 1-ethyl-3-methylimidazolium cations; chloride, bromide, tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, bis(trifluoromethanesulfonyl)imide, tetrachloroaluminate, acetate, hydrogen sulfate, trifluoroacetate or methanesulfonate anion with a 1-butyl-3-methylimidazolium cation; -methylphosphonate anion and 1,3-dimethylimidazolium cation; -bis(trifluoromethanesulfonyl)imide anion and 1-propyl-2,3-dimethylimidazolium cation; -bis(trifluoromethanesulfonyl)imidotetrafluoroborate anion and 1-butyl-2,3-dimethylimidazolium cation; - tetrafluoroborate, hexafluorophosphate or bis(trifluoromethanesulfonyl)imide anion and 1-hexyl-3-methylimidazolium cation; -bis(trifluoromethanesulfonyl)imide anion and 1-octyl-3-methylimidazolium cation; -chloride, bromide, tetrafluoroborate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide or dicyanamide anion and 1-ethanol-3-methylimidazolium cation.

[0083] Examples which may likewise be mentioned are N-butyl-3-methylpyridinium bromide, N-butylmethyl-4-pyridinium chloride, N-butylmethyl-4-pyridinium tetrafluoroborate, N-butyl-3-methylpyridinium chloride, N-butyl-3-methylpyridinium dicyanamide, N-butyl-3-methylpyridinium methyl sulfate, 1-butyl-3-methylpyridinium tetrafluoroborate, N-butylpyridinium chloride, N-butylpyridinium tetrafluoroborate, N-butylpyridinium tetrafluoroborate, and organic salts based on the pyridinium cation such as N-(3-hydroxypropyl)pyridinium bis(trifluoromethylsulfonate), 1-ethyl-3-hydroxymethylpyridinium ethyl sulfate, N-hexylpyridinium bis(trifluoromethylsulfonyl)imide, N-hexylpyridinium trifluoromethanesulfonate, N-(3-hydroxypropyl)pyridinium bis(trifluoromethylsulfonyl)imide, N-butyl-3-methylpyridinium trifluoromethanesulfonate, N-butyl-3-methylpyridinium hexafluorophosphate, and the like.

[0084] Examples which may also be mentioned are 1-butyl-1-methyl-1-pyrrolidinium chloride, 1-butyl-1-methyl-1-pyrrolidinium dicyanamide, 1-butyl-1-methyl-1-pyrrolidinium trifluoromethanesulfonate, 1-butyl-1-methyl-1-pyrrolidinium tris(pentafluoroethyl), 1-butyl-1-methylpyrrolidinium bis[oxalato(2-)]borate, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-butyl-1-methylpyrrolidinium dicyanamide, 1-butyl-1-methylpyrrolidinium trifluoroacetate, 1-butyl-1-methylpyrrolidinium triflate and 1-(2-methoxyethyl)-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, methyl-1-octyl-1-pyrrolidinium chloride, methyl-1-octyl-1-methylpyrrolidinium bromide, and other organic salts based on the pyrrolidinium cation.

[0085] Mention may also be made of organic salts that combine: - bromide, tetrafluoroborate, hexafluorophosphate or trifluoromethanesulfonate anion and 1-ethyl-1-methylpyrrolidinium cation; chloride, bromide, tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, bis(trifluoromethanesulfonyl)imide, dicyanamide, acetate or hydrogen sulfate anions with 1-butyl-1-methylpyrrolidinium cations; -bis(trifluoromethanesulfonyl)imide anion and N-propyl-N-methylpyrrolidinium cation; -Bis(trifluoromethanesulfonyl)imide anion and 1-methyl-1-propylpiperidinium cation

[0086] Examples of organic salts based on the guanidine cation may also include guanidine trifluoromethylsulfonate, guanidine tris(pentafluoroethyl)trifluorophosphate, and hexamethylguanidine tris(pentafluoroethyl)trifluorophosphate.

[0087] Examples of organic salts based on phosphonium cations include trihexyl(tetradecyl)phosphonium bis[oxalato(2-)]borate; trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; and trihexyl(tetradecyl)phosphonium tris(pentafluoroethyl)trifluorophosphate.

[0088] The above list of organic salts and cations and anions that may be included in the organic salt compositions that may be used in accordance with the present invention is given purely by way of example and is not intended to be exhaustive or limiting.

[0089] Consequently, the addition of any other organic salt can of course be envisaged in the context of the present invention, provided that the decomposition temperature of the organic salt is higher than the temperature to which the composition according to the invention is liable to be exposed.

[0090] According to a specific embodiment, the composition according to the invention also contains at least one inorganic salt, i.e., an alkali metal salt or an alkaline earth metal salt, among which may be mentioned in particular organic acids (mono- or dicarboxylic acids containing 1 to 12 carbon atoms, such as formic acid, acetic acid, propionic acid, oxalic acid, and succinic acid; sulfonic acids containing 1 to 20 carbon atoms, such as methanesulfonic acid, p-toluenesulfonic acid, and thiocyanic acid) or mineral acids (hydrohalic acids, such as hydrochloric acid, hydrobromic acid, perchloric acid, sulfuric acid, and phosphoric acid) and salts of alkali metals such as lithium, sodium, and potassium, as well as salts of alkaline earth metals such as magnesium and calcium. Potassium acetate, lithium acetate, lithium chloride, magnesium chloride, calcium chloride, sodium bromide, potassium bromide, magnesium bromide, lithium, sodium, or potassium perchlorate, potassium sulfate, potassium phosphate, potassium thiocyanate, etc.

[0091] Among these, halides are preferred, with lithium chloride, sodium chloride, potassium chloride, potassium acetate, and potassium perchlorate being preferred. The amount of inorganic salts can generally be 0.001% to 3%, preferably 0.01% to 2%, based on the weight of the composition.

[0092] The composition according to the invention may also comprise one or more additives and / or adjuvants, which may be selected from stabilizers, plasticizers, lubricants, organic or mineral fillers, reinforcing agents, dyes, pigments, nacre, antimicrobial agents, flame retardants, antistatic agents (although it is preferred that no other antistatic agents are present), agents for modifying the viscosity of the copolymer, antioxidants, UV stabilizers, flame retardants, carbon black, carbon nanotubes, mineral or organic dyes, pigments, dyes, release agents, blowing agents, impact agents, anti-shrinkage agents, flame retardants, nucleating agents, and / or any other additive or adjuvant already mentioned and known to a person skilled in the art of thermoplastic polymers.

[0093] According to certain embodiments, the composition of the present invention also comprises at least one agent for improving surface conductivity selected from the following: moisture absorbents; fatty acids; lubricants; metals; metal films; metal powders; metal nanopowders; aluminosilicates; amines, such as quaternary amines; esters; fibers; carbon black; carbon fibers; carbon nanotubes; polyethylene glycol; intrinsically conductive polymers such as polyaniline, polythiophene or polypyrrole derivatives; masterbatches; and mixtures thereof.

[0094] The present invention also relates to the use of the composition according to the invention for producing at least one part of the following objects: industrial parts, automotive parts, safety accessories, signs, illuminated banners, signposts and advertising panels, displays, sculptures, furniture, shop fittings, decorations, contact balls, dental prostheses, ophthalmic implants, hemodialysis membranes, optical fibres, works of art, decorations, statues, lenses, in particular camera lenses, disposable camera lenses, printing media, in particular photo boards, windows, panoramic roofs, media for direct printing with UV inks for vehicle headlights, etc. [Example]

[0095] The following examples illustrate the invention without limiting it.

[0096] The following compositions were prepared by blending PMMA polymer and PEBA copolymer:

[0097] The PMMA polymer used is a neat copolymer containing no impact modifiers. PMMA1: advantageously composed of 89% MMA and 11% ethyl acrylate (EA) copolymer, its molar mass being between 70000 g / mol and 80000 g / mol and having a loss factor tan δ equal to 30. PMMA2: advantageously composed of 89% MMA and 11% ethyl acrylate (EA) copolymer, its molar mass ranges from 75000 g / mol to 85000 g / mol and it has a loss factor tan δ equal to 15. PMMA3: advantageously composed of 99.4% MMA and 0.6% ethyl acrylate (EA) copolymer, its molar mass ranges from 75 000 g / mol to 85 000 g / mol and it has a loss factor tan δ equal to 4.6. PMMA4: advantageously composed of 95% MMA and 5% methacrylic acid (MAA) copolymer, its molar mass ranges from 75000 g / mol to 85000 g / mol and it has a loss factor tan δ equal to 3.7. PMMA5: advantageously composed of 94% MMA and 6% ethyl acrylate (EA) copolymer, its molar mass is between 110 000 g / mol and 120 000 g / mol and it has a loss factor tan δ equal to 3.1.

[0098] The PEBA polymers used were as follows: PEBA1: PA11-PEG (40 / 60) with a PA 11 block having a number average molar mass of 1000 g / mol and a PEG block having a number average molar mass of 1500 g / mol; - PEBA2: PA12-PEG (50 / 50) with a PA 12 block having a number average molecular weight of 1500 g / mol and a PEG block having a number average molecular weight of 1500 g / mol.

[0099] The loss factor tanδ of PMMA polymer was measured at 220°C using a parallel plate oscillatory rheometer with a 25 mm diameter plate and a frequency sweep test from 628 to 0.0628 rad / s at strain amplitudes of 2 to 15%, with the value at 1 rad / s taken as the reference.

[0100] Haze, log surface resistivity (logSR), Vicat point and impact strength were measured for the various compositions and the results are shown in the table below. TIFF0007792347000002.tif119170

[0101] The haze of each composition was measured according to the ASTM D 1003 standard.

[0102] The surface resistivity was measured using a Sefelec M1500P machine equipped with an 8009 cell under the following conditions: -Ddp:40V; -Charging time before reading: 60 seconds; -L / D ratio: 53.4.

[0103] No specific conditioning was performed.

[0104] The impact strength was measured according to the ISO 179 / 1eU standard.

[0105] The Vicat point was measured according to the ISO 306B50 standard.

[0106] The composition according to the present invention comprises - have improved antistatic or anti-dust properties compared to PMMA alone; -has improved impact strength compared to PMMA alone; -Good transparency; -has better antistatic or antidust properties than comparative compositions for an equal PEBA content; - For equal PEBA content, compared to the comparative composition, it shows less change in Vicat point than PMMA alone It is found that:

Claims

1. - 85% to 98% by weight, relative to the weight of the composition, of poly(methyl methacrylate) which has a loss factor tan δ, which is the ratio of the elastic moduli G″ and G′, measured at a temperature of 220°C and an angular frequency of 1 rad / s, of at least 10; - 2% to 15% by weight, relative to the weight of the composition, of a copolymer containing polyamide blocks and polyether blocks; A composition comprising:

2. The composition of claim 1 , wherein the poly(methyl methacrylate) comprises a methyl methacrylate (MMA) copolymer.

3. 3. The composition of claim 2, wherein the MMA copolymer comprises 60% to 99.7% by weight of MMA and 0.3% to 40% by weight of at least one monomer containing at least one ethylenic unsaturation that can be copolymerized with MMA.

4. 10. The composition of claim 1, wherein the copolymer containing polyamide blocks and polyether blocks comprises polyethylene glycol (PEG).

5. 5. The composition of claim 4, wherein the copolymer containing polyamide blocks and polyether blocks also comprises at least one polyether other than polyethylene glycol (PEG) selected from polypropyl glycol (PPG), polytrimethylene glycol (PO3G), polytetramethylene glycol (PTMG), and mixtures thereof.

6. The polyamide (PA) blocks of the copolymer containing polyamide blocks and polyether blocks are the following polyamide (PA) blocks: 6, 11, 12, 5.4, 5.9, 5.10, 5.12, 5.13, 5.14, 5.16, 5.18, 5.36, 6.4, 6.9, 6.10, 6.12, 6.13, 6.14, 6.16, 6.18, 6.36, 10.4, 10.9, 10.10, 10.12, 10.13, 10.14, 10.16, 10.18, 10.36, 10.T, 12.4, 12.9, 12.10, 12.12, 12.13, 12.14, 12.16, 12.18, 12.36, 12.

6. The composition of claim 1, wherein the hydroxybenzoate is selected from the group consisting of hydroxybenzoates, ...

7. 7. The composition according to any one of claims 1 and 4 to 6, wherein the polyamide blocks of the copolymer containing polyamide blocks and polyether blocks comprise at least 30 wt. % of PA 11 or PA 12, based on the total weight of the polyamide blocks.

8. 2. The composition of claim 1, wherein the copolymer containing polyamide blocks and polyether blocks is selected from the following copolymers: PA 6-PEG, PA 11-PEG, PA 12-PEG, PA 10.10-PEG, PA 10.12-PEG, PA 6.12-PEG, and mixtures thereof.

9. 9. The composition of claim 1, which is free of organic salts.

10. 10. Use of a composition according to any one of claims 1 to 9 for manufacturing at least one part of the following objects: industrial parts, automotive parts, safety accessories, signs, illuminated banners, signposts and advertising panels, displays, sculptures, furniture, shop fittings, decorations, contact balls, dental prostheses, ophthalmic implants, hemodialysis membranes, optical fibres, works of art, statues, camera lenses, disposable camera lenses, printing media, photo boards, windows, media for direct printing with UV inks for panoramic roofs.

Images