(METH)ACRYLIC COMPOSITION, POLYMERIC COMPOSITE MATERIAL OBTAINED FROM SUCH A COMPOSITION, PROCESS FOR THE PRODUCTION OF SAID COMPOSITION AND MATERIAL, AND USES THEREOF

Abstract

(Meth)acrylic composition, POLYMERIC composite material obtained from such a composition, process for the production OF SAID COMPOSITION AND SAID MATERIAL, and uses thereof. The present invention relates to a (meth)acrylic composition suitable for (meth)acrylic polymer compositions and composites, its preparation process, and its use. In particular, the present invention relates to a (meth)acrylic composition which, once polymerized, possesses a certain heat resistance and is suitable for (meth)acrylic composites used at higher temperatures. More particularly, the present invention relates to a (meth)acrylic composition suitable for the preparation of (meth)acrylic polymer composite compositions and materials.The present invention also relates to a process for preparing and using such a (meth)acrylic composition, as well as to (meth)acrylic polymeric composite compositions and materials prepared from such a (meth)acrylic composition. Furthermore, the invention also relates to a manufacturing process and the uses of such a composite material, which can be applied in numerous industrial sectors.

Description

Title of the invention: (Method)acrylic composition, POLYMERIC composite material obtained from such a composition, process for the production OF SAID COMPOSITION AND OF SAID MATERIAL and uses thereof technical field

[0001] The present invention relates to a (meth)acrylic composition suitable for (meth)acrylic polymeric compositions and composites, its preparation process and its use.

[0002] In particular, the present invention relates to a (meth)acrylic composition which once polymerized it possesses a certain resistance to heat and is suitable for (meth)acrylic composites used at high temperatures.

[0003] More particularly, the present invention relates to a (meth)acrylic composition suitable for the preparation of polymeric (meth)acrylic compositions and composite materials.

[0004] The present invention also relates to a process for the preparation of such a (meth)acrylic composition and its use, but also to (meth)acrylic polymeric composite compositions and materials prepared from such a (meth)acrylic composition.

[0005] Furthermore, the invention also relates to a manufacturing process and the uses of such a composite material which can be applied in many industrial sectors. [Technical problem]

[0006] Compositions comprising (meth)acrylic polymers are widely used. This is mainly due to the characteristic that these polymers are highly transparent polymeric materials exhibiting excellent resistance to ultraviolet radiation and weathering. However, (meth)acrylic polymers are also used in applications where transparency is not necessarily required, such as in polymer composites.

[0007] A composite material is a macroscopic combination of two or more immiscible materials. The composite material consists of at least one matrix material that forms a continuous phase for the cohesion of the structure and a reinforcing material having various architectures for mechanical properties.

[0008] The objective of using composite materials is to achieve a performance from the composite material that is not available from its constituents. separate if used alone. Therefore, composite materials are widely used in several industrial sectors such as building, automotive, aerospace, transport, leisure, electronics and sport, particularly because of their better mechanical performance (higher tensile strength, higher tensile modulus, higher fracture toughness) compared to homogeneous materials and their low density.

[0009] One of the most important classes in terms of volume on a commercial industrial scale is composites comprising organic matrices, where the matrix material is generally a polymer. The matrix or main continuous phase of a polymeric composite material is either a thermoplastic polymer or a thermosetting polymer.

[0010] Thermosetting polymers consist of cross-linked three-dimensional structures. Cross-linking is achieved by hardening reactive groups in the so-called prepolymer. Hardening can, for example, be achieved by heating the polymer chains to cross-link and permanently harden the material. To prepare the polymeric composite material, the prepolymer is mixed with the other component (for example, glass beads for a particulate composite or short fibers for a fibrous composite), or the other component is wetted or impregnated (for example, woven mesh), and then hardened.

[0011] Examples of prepolymers or matrix materials for thermosetting polymers include unsaturated polyesters, vinyl esters, epoxies, and phenolics. This manufacturing process for semi-finished products results in what are known as prepregs.

[0012] One disadvantage of a thermosetting polymer matrix is ​​its very high cross-linking. The matrix cannot easily be shaped into other forms. Once the polymer has hardened, the shape is fixed. Also, recycling thermosetting polymers or composites based on thermosetting polymers is difficult or impossible. Another problem is the environmental or health impact of the raw materials for thermosetting polymers.

[0013] Thermoplastic polymers consist of, or comprise, linear, branched, or slightly cross-linked polymer chains. Thermoplastic polymers can be heated to mix the two constituents necessary for the production of the composite material and then cooled to set. One limitation to the use of these thermoplastic polymers for manufacturing composite materials is their high viscosity in the molten state. Proper wetting or impregnation of the fibers by the thermoplastic polymer can only be achieved if the thermoplastic resin is sufficiently fluid. In order to obtain low viscosity or sufficient fluidity of the thermoplastic polymer, the The chain length (or molecular weight) can be reduced. However, a molecular weight that is too low negatively impacts the performance of the composite material, particularly its mechanical properties. On the other hand, the temperature of the thermoplastic polymer could be increased to significantly reduce its viscosity. Consequently, the continuous operating temperature is relatively high, exceeding 200 °C, which directly affects the economics (costs) of the composite material due to the associated high energy costs.

[0014] Furthermore, thermoplastic polymers tend to degrade at very high temperatures, which is particularly true for semi-crystalline thermoplastic polymers with high melting points, such as polyamides (e.g., PA6.6), polyethersulfone (PES), polyetherimide (PEI), polyetheretherketone (PEEK), or poly(phenylene sulfide) (PPS). This heat-induced degradation leads to a decrease in the molecular weight of the polymer matrix, which is important for the cohesion of the composite material.

[0015] Another possibility for impregnating the fibrous substrate is to dissolve the thermoplastic polymer in an organic solvent. However, this method requires a large quantity of solvent, which must be evaporated. The use of large quantities of solvent presents environmental problems in terms of energy consumption and pollution.

[0016] Another way to prepare a polymeric composite material based on thermoplastic polymers is with a thermoplastic polymer resin comprising a monomer, commonly called a "syrup." The syrup is used for mixing with or impregnating the reinforcing material, for example, a filler or a fibrous substrate. Once polymerized, meaning that the monomer has polymerized, the thermoplastic polymeric resin constitutes the matrix of the composite material. During mixing or impregnation in the preparation of polymer composites, the viscosity of the impregnating syrup must be controlled and adjusted so that it is neither too fluid nor too viscous, in order to obtain a homogeneous mixture with a filler or to properly impregnate each fiber of the fibrous substrate.When wetting is incomplete, depending on whether the syrup is too fluid or too viscous, "bare" areas—that is, unimpregnated areas—and areas where polymer droplets form on the fibers, causing bubble formation, respectively, appear. These "bare" areas and bubbles lead to defects in the final composite material, which, among other things, cause a loss of mechanical strength. However, the useful viscosity range for impregnation is narrow for storing such a material.

[0017] One disadvantage for the preparation of thermoplastic composite with respective reinforcements from a syrup is the degradation of the polymer when the composite is used at a higher temperature.

[0018] There is a need for a polymeric composition that provides high thermal resistance and resistance to aging at higher temperatures.

[0019] There is also a need for a polymeric composition that provides high thermal resistance and resistance to aging at higher temperatures as a continuous phase in polymer composites.

[0020] There is also a need to replace thermosetting polymers in composites with polymers that are more easily recyclable and use raw materials that pose fewer environmental and / or health problems.

[0021] There is also a need for a satisfactory shelf life of the composition before polymerization, which leads to said polymeric composition. The composition should be stable for handling during the preparation of the mixture with a filler or during the impregnation of fibers or the fibrous substrate.

[0022] The objective of the present invention is to have a composition for the preparation of (meth)acrylic polymer compositions exhibiting high thermal resistance and resistance to aging at increased temperatures.

[0023] The objective of the present invention is also to have a composition for the preparation of a (meth)acrylic composite composition exhibiting high thermal resistance and resistance to aging at increased temperatures.

[0024] The objective of the present invention is also to provide a (meth)acrylic composition for the preparation of (meth)acrylic polymeric compositions or of a (meth)acrylic composite composition, said (meth)acrylic composition having a satisfactory service life limit.

[0025] The term "high thermal resistance" in the present invention means a weight loss of the polymerized composition or composite composition at a temperature above 150 °C or even 160 °C. The weight loss must be reduced over a period of, for example, 2,000 hours of exposure to high temperature and preferably, the weight loss of the polymer part at a temperature of 150 °C must be less than 10% over a period of 2,000 hours, more preferably at a temperature of 170 °C must be less than 10% over a period of 5,000 hours and even more preferably at a temperature of 170 °C must be less than 5% over a period of 5,000 hours.

[0026] The terms "sufficient shelf life" in the present invention mean that the (meth)acrylic composition can be handled and stored at 20 °C for at least 12 hours, preferably at least 24 hours without polymerization.

[0027] Another objective of the present invention is to provide a process for the preparation of a (meth)acrylic composition having a sufficient service life limit useful for the preparation of a (meth)acrylic composite composition exhibiting high thermal resistance.

[0028] Yet another objective of the present invention is to have a process for the preparation of a (meth)acrylic composite composition having high thermal resistance which can also be recycled. [CONTEXT OF THE INVENTION] Prior art

[0029] Document WO2013 / 056845 describes a composite material obtained by in-situ polymerization of thermoplastic (meth)acrylic resins. The polymeric composite material obtained by in-situ polymerization of a thermoplastic (meth)acrylic resin and a fibrous material containing long fibers, and its use, a process for manufacturing such a composite material, and a manufactured mechanical or structured part or article comprising this polymeric composite material. The polymerization uses a radical initiator selected from diacyl peroxides, peroxyesters, dialkyl peroxides, peroxyacetals, or azo compounds. The document does not disclose anything concerning the composition of the polymeric composite obtained and its resistance to aging, particularly at elevated temperatures.

[0030] Document WO2014 / 013028 describes an impregnation process for a substrate The document describes a fibrous material, a liquid (meth)acrylic syrup for the impregnation process, its polymerization method, and the resulting structured article. The liquid (meth)acrylic syrup comprises a (meth)acrylic polymer, a (meth)acrylic monomer, and at least one initiator or initiation system to start the polymerization of the (meth)acrylic monomer. The initiators or initiation systems are heat-activated. The document does not disclose the composition of the polymeric composite or its resistance to aging, particularly at elevated temperatures.

[0031] Document WO2020 / 002842 discloses a (meth)acrylic composition comprising 100 parts by weight of a liquid (meth)acrylic syrup, 20 parts by weight to 300 parts by weight of a mineral filler C, 0.01 parts by weight to 5 parts by weight of a (meth)acrylic monomer M2, the monomer M2 comprising at least two (meth)acrylic functions per monomer, 0.01 parts by weight to 5 parts by weight of a (meth)acrylic monomer M3 and 0.01 parts by weight to 5 parts by weight of a polymerization initiator.

[0032] Document WO2020 / 078991 discloses an MCI (meth)acrylic composition comprising 100 parts of a liquid (meth)acrylic syrup, between 0.01 and 10 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions, from 0 to 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function, said (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1) and other possible compounds.

[0033] None of the prior art documents disclose a suitable (meth)acrylic composition for (meth)acrylic polymer compositions or composites which simultaneously have improved heat aging and service life properties. [Brief description of the invention]

[0034] Surprisingly, it was also found that a (meth)acrylic MCI composition comprising:

[0035] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0036] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0037] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0038] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0039] C) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0040] makes it possible to provide a composition for the preparation of (meth)acrylic polymers or composites which have better resistance to heat aging than a composition or composite not comprising components b) and c).

[0041] Surprisingly, it was also discovered that a (meth)acrylic MCI composition comprising:

[0042] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0043] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0044] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0045] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0046] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function, the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (Ml);

[0047] can be used to increase the resistance to heat aging of a polymer or polymeric composite material formed from this composition compared with a composition not comprising components b) and c).

[0048] Surprisingly, this process has also been discovered for the preparation of (meth)acrylic polymer compositions or for the preparation of a (meth)acrylic composite composition, said process comprising the steps of:

[0049] i) provide an MCI (meth)acrylic composition comprising:

[0050] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0051] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0052] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0053] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0054] c) 0.1 to 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C

[0055] ii) polymerize said (meth)acrylic MCI composition

[0056] leads to a composition of (meth)acrylic polymers or composites that have better resistance to heat aging compared with a composition or composite not comprising components b) and c). Description of embodiments

[0057] According to a first aspect, the present invention relates to an MCI (meth)acrylic composition, said composition comprising:

[0058] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0059] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0060] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0061] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0062] c) from 0.1 to 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function, the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (Ml).

[0063] According to a second aspect, the present invention relates to a (meth)acrylic (MCI) composition comprising:

[0064] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0065] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0066] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0067] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0068] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function, the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1); and

[0069] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0070] e) possibly an inorganic filler Cl or fibers or fibrous material.

[0071] According to a third aspect, the present invention relates to a process for preparing a (meth)acrylic MCI composition comprising the following steps:

[0072] i) supplying the following components

[0073] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0074] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI), and

[0075] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) including a single meth)acrylic function

[0076] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions

[0077] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0078] ii) mixing components a) to c).

[0079] According to a fourth aspect, the present invention relates to the use of a (meth)acrylic MCI composition to be mixed with an inorganic filler Cl or to impregnate a fibrous substrate, said (meth)acrylic MCI composition comprising:

[0080] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0081] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0082] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0083] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0084] c) from 0.1 to 10 phr by weight and preferably between 0.5 and 4 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0085] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3).

[0086] According to a fifth aspect, the present invention relates to the use of an MCI (meth)acrylic composition to prepare an MPI (meth)acrylic polymeric composition, said MCI (meth)acrylic composition comprising:

[0087] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0088] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0089] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0090] b) between 0.01 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0091] c) between 0.1 and 10 phr by weight and preferably between 0.5 and 4 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0092] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3).

[0093] According to a sixth aspect, the present invention relates to a process for preparing a polymeric composite from an MCI (meth)acrylic composition, said process comprising the following steps:

[0094] i) impregnation of a fibrous substrate or mixing of an inorganic filler Cl with a (meth)acrylic MCI composition comprising:

[0095] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0096] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0097] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0098] b) between 0.01 and 10 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0099] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0100] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0101] ii) the polymerization of the (meth)acrylic composition MCI.

[0102] According to a seventh aspect, the present invention relates to a process for preparing a (meth)acrylic polymeric composition from an MCI (meth)acrylic composition, said process comprising the following steps:

[0103] i) supply of an MCI (meth)acrylic composition comprising:

[0104] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0105] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0106] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0107] b) between 0.01 and 10 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0108] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized in the form of a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0109] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0110] ii) the polymerization of the (meth)acrylic composition MCI.

[0111] The term "(meth)acrylic", in the present context, refers to all types of acrylic and methacrylic monomers.

[0112] The term “PMMA”, as used, refers to homo- and copolymers of methyl methacrylate (MMA), the weight proportion of MMA in PMMA being at least 70% by weight for the MMA copolymer.

[0113] The term "monomer", as used, refers to a molecule that can undergo polymerization.

[0114] The term “polymerization”, as used, refers to the process of converting a monomer or a mixture of monomers into a polymer.

[0115] The term “thermoplastic polymer”, in this context, refers to a polymer which becomes liquid or becomes more liquid or less viscous when heated and which can take on new shapes by the application of heat and pressure. This also applies to slightly cross-linked thermoplastic polymers that can be thermoformed when heated above the softening temperature.

[0116] The term “thermosetting polymer”, as used, refers to a prepolymer in a soft, solid or viscous state which is irreversibly transformed into an infusible and insoluble polymer network by hardening.

[0117] The term “prepreg”, in this context, refers to a composition of a fibrous substrate which has been impregnated with a curable prepolymer, or liquid reagents or a thermoplastic and can further be polymerized.

[0118] The term “prepolymer”, in the present context, refers to a polymer or oligomer whose molecules are capable of entering, through reactive groups, into further polymerization.

[0119] The term “oligomer”, in the present context, refers to a polymer molecule of intermediate relative molecular mass, comprising between 5 and 500 monomer motifs.

[0120] The term "polymer composite", as used, refers to a multicomponent material comprising several different phase domains, in which at least one type of phase domain is a continuous phase and in which at least one component is a polymer.

[0121] The term “initiator”, in the present context, refers to a chemical species which forms a compound or an intermediate compound which starts the polymerization of a monomer, which is capable of successively linking a large number of other monomers in a polymeric compound.

[0122] The abbreviation "phr" (English for "weight parts per hundred parts") denotes parts by weight per hundred parts of composition. For example, 1 phr of initiator in the composition means that 1 kg of initiator is added to 100 kg of composition.

[0123] The abbreviation "ppm" stands for parts by weight per million parts of composition. For example, 1000 ppm of a compound in the composition means that 0.1 kg of the compound is present in 100 kg of the composition.

[0124] By specifying that a range is from x to y in the present invention, this means that the upper and lower limits of this range are included, which is equivalent to at least x and up to y.

[0125] By specifying that a range is between x and y in the present invention, this means that the upper and lower limits of this range are excluded, which is equivalent to more than x and less than y.

[0126] The liquid composition a) or the liquid (meth)acrylic syrup comprises a (meth)acrylic polymer (PI) and a (meth)acrylic monomer (Ml).

[0127] The liquid (meth)acrylic syrup comprises between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI) and between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml). Preferably, the liquid (meth)acrylic syrup comprises between 10% by weight and 40% by weight of a (meth)acrylic polymer (PI) and between 60% by weight and 90% by weight of a (meth)acrylic monomer (Ml); and more preferably between 10% by weight and 30% by weight of a (meth)acrylic polymer (PI) and between 70% by weight and 90% by weight of a (meth)acrylic monomer (Ml)

[0128] The dynamic viscosity of the liquid composition a) or of the liquid (meth)acrylic syrup is in a range of 10 mPa*s to 10,000 mPa*s, preferably from 20 mPa*s to 7,000 mPa*s and advantageously from 20 mPa*s to 5,000 mPa*s and more advantageously from 20 mPa*s to 2,000 mPa*s and even more advantageously between 20 mPa*s and 1,000 mPa*s.The viscosity of the syrup can easily be measured with a rheometer or viscometer. Dynamic viscosity is measured at 25 °C. If the liquid (meth)acrylic syrup exhibits Newtonian behavior, meaning it does not flow under shear, the dynamic viscosity is independent of shear rate in a rheometer or of the moving part speed in a viscometer. If the liquid composition LC1 exhibits non-Newtonian behavior, meaning it does flow under shear, the dynamic viscosity is measured at a shear rate of 1 s⁻¹ at 25 °C.

[0129] With regard to the liquid (meth)acrylic syrup a) which comprises the (meth)acrylic monomer (Ml) and the (meth)acrylic polymer (P1), the (meth)acrylic monomer (Ml), once polymerized, is transformed into a (meth)acrylic polymer (P2) comprising the monomeric units of the (meth)acrylic monomer (Ml) and other possible monomers such as (M2) and (M3). The (meth)acrylic polymeric composition (P1) comprises the (meth)acrylic polymer (P1) and the (meth)acrylic polymer (P2).

[0130] With regard to the (meth)acrylic (PI) polymer, mention may be made of poly(alkyl methacrylate) or poly(alkyl acrylate). By the terms "poly(alkyl methacrylate) or poly(alkyl acrylate)", it is understood that the polymer comprises at least 70% by weight of monomeric units derived respectively from an alkyl ester of methacrylic acid or acrylic acid. In a preferred embodiment, the (meth)acrylic (PI) polymer is poly(methyl methacrylate) (PMMA).

[0131] The term “PMMA” refers to a homopolymer or copolymer of methyl methacrylate (MMA) or mixtures thereof.

[0132] According to one embodiment, the methyl methacrylate (MMA) homo- or copolymer comprises at least 70%, preferably at least 80%, advantageously at least 90% and more advantageously at least 95% by weight of methyl methacrylate.

[0133] According to another embodiment, PMMA is a mixture of at least one homopolymer and at least one copolymer of MMA, or a mixture of at least two homopolymers or two copolymers of MMA having a different average molecular weight, or a mixture of at least two copolymers of MMA having a different monomer composition.

[0134] The methyl methacrylate (MMA) copolymer comprises from 70% to 99.9% by weight of methyl methacrylate and from 0.1% to 30% by weight of at least one monomer containing at least one ethylenic unsaturation which can be copolymerized with methyl methacrylate.

[0135] These monomers are well known, and in particular, mention may be made of acrylic and methacrylic acid esters such as alkyl (meth)acrylates in which the alkyl group contains from 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 from 1 to 4 carbon atoms.

[0136] According to a first preferred embodiment, the methyl methacrylate (MMA) copolymer comprises from 80% to 99.9%, advantageously from 90% to 99.9%, and more advantageously from 90% to 99.9% by weight of methyl methacrylate, and from 0.1% to 20%, advantageously from 0.1% to 10%, and more advantageously from 0.1% to 10% by weight of at least one monomer containing at least one ethylenic unsaturation that can be copolymerized with the methyl methacrylate. Preferably, the comonomer is selected from methyl acrylate and ethyl acrylate, and mixtures thereof.

[0137] The average molecular mass by weight of the (meth)acrylic (PI) polymer must be high, meaning greater than 50,000 g / mol and preferably greater than 100,000 g / mol.

[0138] The average molecular mass by weight can be measured by size exclusion chromatography (SEC).

[0139] The (meth)acrylic (PI) polymer is completely soluble in the (meth)acrylic (Ml) monomer or in the mixture of (meth)acrylic monomers. This increases the viscosity of the (meth)acrylic (Ml) monomer or the mixture of (meth)acrylic monomers. The resulting solution is a liquid composition generally referred to as a "syrup" or "prepolymer." The dynamic viscosity of the liquid (meth)acrylic syrup ranges from 10 mPa·s to 10,000 rnPa·s. The viscosity of the syrup can be easily measured with a rheometer or viscometer. The dynamic viscosity is measured at 25 °C.

[0140] Advantageously, the composition or liquid (meth)acrylic syrup does not contain any additional solvent intentionally added.

[0141] With regard to the monomer (meth jacrylic (Ml), the monomer is selected from alkylacrylic monomers, alkylmethacrylic monomers, hydroxyalkylacrylic monomers, and hydroxyalkylmethacrylic monomers, and mixtures thereof. The terms "alkylacrylic monomers" and "alkylmethacrylic monomers" refer to the fact that the monomers are an alkyl ester of methacrylic acid or acrylic acid.

[0142] Preferably, the (meth)acrylic monomer (Ml) is selected from hydroxyalkylacrylic monomers, hydroxyalkylmethacrylic monomers, alkylacrylic monomers, alkylmethacrylic monomers and mixtures thereof, the alkyl group containing from 1 to 22 linear, branched or cyclic carbon atoms, the alkyl group preferably containing from 1 to 12 linear, branched or cyclic carbon atoms.

[0143] Advantageously, the (meth)acrylic monomer (Ml) is selected from methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, isobutyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate and mixtures thereof.

[0144] According to a preferred embodiment, at least 50% by weight and preferably at least 60% by weight of the (meth)acrylic monomer (Ml) is methyl methacrylate.

[0145] According to a first more preferred embodiment, at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, advantageously at least 80% by weight and even more advantageously 90% by weight of the monomer (Ml) is a mixture of methyl methacrylate with optionally at least one other monomer.

[0146] According to a second, more preferred embodiment, the monomer (Ml) is methyl methacrylate.

[0147] With regard to the (meth)acrylic (M2) monomer, the monomer is multifunctional. The (meth)acrylic (M2) monomer comprises at least two functional groups that can undergo polymerization. The (meth)acrylic (M2) monomer is different from the (meth)acrylic (M1) monomer. The (meth)acrylic (M2) monomer is also different from the (meth)acrylic (M3) monomer.

[0148] The (meth)acrylic monomer (M2) may be selected from 1,3-butylene glycol dimethacrylate; 1,4-butanediol dimethacrylate; 1,6-hexanediol diacrylate; 1,6-hexanediol dimethacrylate; diethylene glycol dimethacrylate; the dipropylene glycol diacrylate; bisphenol A ethoxylated diacrylate (10); bisphenol A ethoxylated dimethacrylate (2); bisphenol A ethoxylated diacrylate (3); bisphenol A ethoxylated dimethacrylate (3); bisphenol A ethoxylated diacrylate (4); bisphenol A ethoxylated dimethacrylate (4); bisphenol A ethoxylated dimethacrylate; bisphenol ethoxylated dimethacrylate (10); ethylene glycol dimethacrylate; polyethylene glycol diacrylate (200); polyethylene glycol diacrylate (400); polyethylene glycol dimethacrylate (400); polyethylene glycol dimethacrylate (400); polyethylene glycol diacrylate (600); polyethylene glycol dimethacrylate (600); polyethylene glycol diacrylate 400; neopentyl glycol propoxylated diacrylate (2); tetraethylene glycol diacrylate; tetraethylene glycol dimethacrylate; tricyclodecanedimethanol diacrylate; tricyclodecanedimethanol dimethacrylate;triethylene glycol diacrylate; triethylene glycol dimethacrylate; tripropylene glycol diacrylate; ethoxylated trimethylolpropane triacrylate (15); ethoxylated trimethylolpropane triacrylate (3); ethoxylated trimethylolpropane triacrylate (6); ethoxylated trimethylolpropane triacrylate (9); ethoxylated pentaerythritol triacrylate 5; ethoxylated trimethylolpropane triacrylate (20); propoxylated glyceryl triacrylate (3); trimethylolpropane triacrylate; propoxylated glyceryl triacrylate (5.5); pentaerythritol triacrylate; propoxylated glyceryl triacrylate (3); propoxylated trimethylolpropane triacrylate (3); trimethylolpropane triacrylate; trimethylolpropane trimethacrylate; tris(2-hydroxyethyl) isocyanurate triacrylate; ditrimethylolpropane tetraacrylate; dipentaerythritol pentaacrylate; ethoxylated pentaerythritol tetraacrylate (4); pentaerythritol tetraacrylate;Dipentaerythritol hexaacrylate; 1,10-Decanediol diacrylate; 1,3-Butylene glycol diacrylate; 1,4-Butanediol diacrylate; 1,9-Nonanediol diacrylate; 2-(2-Vinyloxyethoxy)ethyl acrylate; 2-Butyl-2-ethyl-1,3-propanediol diacrylate; 2-Methyl-1,3-propanediol diacrylate; 2-Methyl-1,3-propanediyl ethoxyacrylate; 3-Methyl-1,5-Pentanediol diacrylate; Alkoxylated cyclohexanedimethanol diacrylate; Alkoxylated hexanediol diacrylate; Cyclohexanedimethanol diacrylate; Ethoxylated cyclohexanedimethanol diacrylate; Diethylene glycol diacrylate; Dioxaneglycol diacrylate; ethoxylated dipentaerythritol hexaacrylate; ethoxylated glycerol triacrylate; ethoxylated neopentylglycol diacrylate; hydroxypivalyl hydroxypivalate diacrylate; neopentylglycol diacrylate; poly(tetramethylene glycol) diacrylate; polypropylene glycol 400 diacrylate;polypropylene glycol diacrylate 700; propoxylated ethoxylated bisphenol A diacrylate (6); propoxylated ethylene glycol diacrylate; tetraacrylate of; propoxylated pentaerythritol (5); and propoxylated trimethylolpropane triacrylate; or corresponding mixtures.

[0149] Preferably, the (meth)acrylic monomer (M2) is selected from a compound comprising at least two (meth)acrylic groups. The (meth)acrylic monomer (M2) may also be selected from a mixture of at least two compounds (M2a) and (M2b), each comprising at least two (meth)acrylic groups.

[0150] In a first preferred embodiment, the (meth)acrylic monomer (M2) is chosen from tricyclodecanedimethanol diacrylate and tricyclodecanedimethanol dimethacrylate.

[0151] In a second preferred embodiment, the (meth)acrylic monomer (M2) is selected from ethoxylated bisphenol A diacrylate (10); ethoxylated bisphenol A dimethacrylate (2); ethoxylated bisphenol A diacrylate (3); ethoxylated bisphenol A dimethacrylate (3); ethoxylated bisphenol A diacrylate (4); ethoxylated bisphenol A dimethacrylate (4); ethoxylated bisphenol A dimethacrylate; ethoxylated bisphenol A dimethacrylate (10) and mixtures thereof.

[0152] The (meth)acrylic monomer (M2) may be present in the (meth)acrylic MCI composition between 0.1 and 9 phr by weight, preferably is present between 0.1 and 8 phr per 100 parts of a liquid (meth)acrylic syrup, more preferably between 0.1 and 7 phr, even more preferably between 0.1 and 6 phr and advantageously between 0.1 and 5 phr.

[0153] In a first preferred embodiment, the (meth)acrylic monomer (M2) is present in the (meth)acrylic MCI composition between 0.5 and 5 phr and is chosen from a compound or a mixture of compounds comprising two (meth)acrylic functions.

[0154] In a second preferred embodiment, the (meth)acrylic monomer (M2) is present in the (meth)acrylic MCI composition between 2.5 and 5 phr and is chosen from a compound or a mixture of compounds comprising two (meth)acrylic functions.

[0155] In a third preferred embodiment, the (meth)acrylic monomer (M2) is present in the (meth)acrylic MCI composition between 0.1 and 5 phr and is chosen from a mixture of compounds comprising at least two (meth)acrylic functions.

[0156] In a fourth, more preferred embodiment, the (meth)acrylic monomer (M2) is present in the (meth)acrylic MCI composition between 0.1 and 5 phr and is selected from a mixture of compounds comprising at least two (meth)acrylic functional groups. At least one compound in the mixture comprises only two (meth)acrylic functional groups and represents at least 50% by weight of the (meth)acrylic monomer (M2) mixture, preferably at least 60% by weight.

[0157] With regard to the (meth)acrylic monomer (M3), the monomer is selected from a monomer which, once polymerized as a homopolymer, has a glass transition temperature Tg of at least 110 °C, preferably at least 120 °C. The glass transition temperature of homopolymers can be found in the "Polymer Handbook". The glass transition temperature can also preferably be measured by differential scanning calorimetry (DSC) according to ISO 11357-2:2020 "Plastics — Differential scanning calorimetry (DSC) — Part 2: Determination of glass transition temperature and plateau height".

[0158] The (meth)acrylic monomer (M3) is different from the (meth)acrylic monomers (M1) and (M2).

[0159] The (meth)acrylic monomer (M3) in a preferred embodiment being selected from methacrylic acid, isobomyl methacrylate, tert-butyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl methacrylate and mixtures thereof.

[0160] The (meth)acrylic monomer (M3) in a first preferred embodiment is chosen from methacrylic acid.

[0161] The (meth)acrylic monomer (M3) may be present in the (meth)acrylic MCI composition between 0.1 and 10 phr by weight, preferably between 0.1 and 9 phr by weight, more preferably between 0.1 and 8 phr, even more preferably between 0.1 and 7 phr, even more preferably between 0.5 and 6 phr and even more preferably between 0.5 and 2 phr per 100 parts of a liquid (meth)acrylic syrup.

[0162] In a first most preferred embodiment, the (meth)acrylic monomer (M3) is present in the (meth)acrylic MCI composition between 0.1 and 5 phr by weight per 100 parts of a liquid (meth)acrylic syrup.

[0163] In a second most preferred embodiment, the (meth)acrylic monomer (M3) is present in the (meth)acrylic MCI composition between 0.1 and 4 phr by weight per 100 parts of a liquid (meth)acrylic syrup.

[0164] In a third most preferred embodiment, the (meth)acrylic monomer (M3) is present in the (meth)acrylic MCI composition between 0.1 and 2 phr by weight per 100 parts of a liquid (meth)acrylic syrup.

[0165] According to the invention, the quantity ranges of components a) to c) in the (meth)acrylic MCI composition can be combined in any combination, for example preferred ranges for component b) with an advantageous range of component c).

[0166] As regards the initiator to start the polymerization of the (meth)acrylic monomers (M1), (M2) and (M3), it is chosen from among the radical initiators.

[0167] Preferably the radical initiator is a peroxide and more preferably the peroxide is liquid over a temperature range between 0 °C and 50 °C.

[0168] According to a particular embodiment, the polymerization initiator has a half-life temperature at 1 hour, which is greater than 70 °C, advantageously greater than 80 °C and preferably greater than 90 °C.

[0169] Preferably the polymerization initiator has a half-life temperature at 1 hour and 1013 mbars between 70 °C and 140 °C, more preferably between 80 °C and 135 °C, and even more preferably between 90 °C and 130 °C and most preferably between 95 °C and 125 °C.

[0170] According to a particular embodiment, the polymerization initiator has a maximum storage temperature of at least 10 °C, advantageously of at least 15 °C.

[0171] The polymerization initiator may in particular comprise from 2 to 30 carbon atoms and may be selected, for example, from tert-amyl peroxypivalate, tert-butyl peroxypivalate, bis(3,5,5-trimethylhexanoyl) peroxide, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethylacetate, tert-butyl peroxyisobutyrate, tert-amylperoxy-l-methoxycyclohexane, 1-methoxy-lt-butylperoxycyclohexane, l-methoxy-lt-amylperoxy-3,3,5-trimethylcyclohexane, 1-methoxy-lt-butylperoxy-3,3,5-trimethylcyclohexane, 1-ethoxy-1-t-amylperoxycyclohexane, 1-ethoxy-lt-butylperoxycyclohexane, 1-ethoxy-lt-butyl-3,3,5-peroxycyclohexane, 1,1-di(terLamylperoxy)cyclohexane, 1,l-di(terLbutylperoxy)-3,3,5-trimethylcyclohexane, l,l-di(tert-butylperoxy)cyclohexane, tert-amyl peroxy-2-ethylhexylcarbonate,tert-butyl peroxy-2-ethylhexylcarbonate, tert-amyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-amyl peroxyacetate, tert-butyl peroxyacetate, 2,2-di(tert-butylperoxy)butane, 2,2-di(tert-amylperoxy)butane, tert-amyl peroxybenzoate, tert-butyl peroxybenzoate, butyl 4,4-di(tert-butylperoxy)valerate, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, tert-butylcumyl peroxide, di-tert-amyl peroxide, di-terL-butyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, hydroperoxide 3,5-Diisopropylbenzene, cumene hydroperoxide, and mixtures thereof.

[0172] In a preferred embodiment, the polymerization initiator is selected from tert-amyl peroxypivalate, tert-butyl peroxypivalate, bis(3,5,5-trimethylhexanoyl) peroxide, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethyl acetate, tert-butyl peroxyisobutyrate, terT-amylperoxy-1-methoxycyclohexane, 1-methoxy-1-t-butylperoxycyclohexane, l-methoxy-lt-amylperoxy-3,3,5-trimethylcyclohexane, 1-methoxy- lt-butylperoxy-3,3,5-trimethylcyclohexane, 1-ethoxy- 1-t-amylperoxycyclohexane, 1-ethoxy- 1-t-butylperoxycyclohexane, 1-ethoxy-1 -t-butyl-3,3,5-peroxycyclohexane, 1,1 -di(tert-amylperoxy)cyclohexane, 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,l-di(tert-butylperoxy)cyclohexane, tert-amyl peroxy-2-ethylhexylcarbonate, tert-butyl peroxy-2-ethylhexylcarbonate, tert-amyl peroxy-3,5,5-trimethylhexanoate, / e / 7-butyl peroxy-3,5,5-trimethylhexanoate, / e / 7-amyl peroxyacetate, tert-butyl peroxyacetate, 2,2-di(tert-butylperoxy)butane, 2,2-di(tert-amylperoxy)butane, tert-amyl peroxybenzoate, tert-butyl peroxybenzoate, butyl 4,4-di(tert-butylperoxy)valerate, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and mixtures thereof.

[0173] In an advantageous embodiment, the polymerization initiator is selected from tert-amylperoxy-l-methoxycyclohexane, 1-methoxy-1-t-butylperoxycyclohexane, 1-methoxy-lt-amylperoxy-3,3,5-trimethylcyclohexane, 1-methoxy-1-t-butylperoxy-3,3,5-trimethylcyclohexane, 1-ethoxy-1-t-amylperoxycyclohexane, 1-ethoxy-1-t-butylperoxycyclohexane, 1-ethoxy-1-t-butyl-3,3,5-peroxycyclohexane and mixtures thereof.

[0174] During its decomposition, such an initiator generates free radicals which contribute to the start of the polymerization reaction.

[0175] The quantity of initiator is between 0.1 parts by weight and 5 parts by weight per 100 parts of the liquid (meth)acrylic syrup, preferably between 0.1 and 4 phr, more preferably between 0.2 and 4 phr, even more preferably between 0.4 and 4 phr and advantageously between 0.5 and 4 phr per 100 parts of a liquid (meth)acrylic syrup.

[0176] The quantity of initiator is supposed to be calculated on the molecule that generates the radicals, in the case where the commercial compound is diluted for example.

[0177] According to the invention, the ranges of quantities of component d) in the (meth)acrylic MCI composition can be combined in any combination with a limit or ranges or choices for components a) to c), for example preferred ranges for components a) to c).

[0178] Preferably the (meth)acrylic MCI composition does not include a polymerization activator.

[0179] The (meth)acrylic MCI composition may include other components such as a coupling agent which promotes the dispersion of the mineral charge C if it is present in the (meth)acrylic MCI composition.

[0180] the amount of coupling agent is between 0.1 parts by weight and 2 parts by weight, preferably between 0.1 parts by weight and 1 part by weight per 100 parts of the (meth)acrylic MCI composition.

[0181] This coupling agent may be a compound comprising functional groups such as an organosilane. This coupling agent may, in particular, be selected from aminosilanes, vinylsilanes, methacrylsilanes, and mixtures thereof. Preferably, the coupling agent is selected from methacrylsilanes.

[0182] The (meth)acrylic MCI composition may include other components such as antioxidants. Regarding the antioxidant, it may be chosen from phenolic antioxidants or phosphite-type antioxidants. IRGANOX® products are an example of phenolic antioxidants.

[0183] The amount of antioxidant in the (meth)acrylic MCI composition can be up to 10,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup.

[0184] The amount of the antioxidant is between 0 ppm by weight and 10,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup. In a particular embodiment, the amount of the transfer agent is preferably between 0.01 ppm by weight and 5,000 ppm by weight and more preferably between 0.1 ppm by weight and 3,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup.

[0185] The (meth)acrylic MCI composition may include other components such as a photostabilizer. For example, the photostabilizer may be chosen from HALS (hazed amine-type photostabilizers) or phosphites.

[0186] For example, HALS may be derivatives of 2,2,6,6-tetramethylpiperidine such as, for example, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate.

[0187] The amount of photostabilizer in the (meth)acrylic MCI composition can be up to 10,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup.

[0188] In a specific embodiment, the quantity of the photostabilizer is preferably between 0.01 ppm by weight and 7,000 ppm by weight and more preferably between 0.1 ppm by weight and 5,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup.

[0189] The (meth)acrylic MCI composition may include other components such as a thermal stabilizing agent, which may for example be chosen from a disulfide-type compound such as poly(tert-amylphenol disulfide).

[0190] The amount of the heat stabilizing agent in the (meth)acrylic MCI composition can be up to 1,000 ppm by weight per 100 parts of a liquid (meth)acrylic syrup.

[0191] In a particular embodiment, the quantity of the thermal stabilizing agent is preferably between 0.01 ppm by weight and 5,000 ppm by weight and more preferably between 0.1 ppm by weight and 3,000 ppm by weight relative to the sum of the (meth)acrylic monomer and the (meth)acrylic polymer.

[0192] With regard to the inorganic charge Cl, mention may be made of short glass fibers, hollow glass microspheres, inorganic compounds such as minerals and salts.

[0193] The inorganic compound includes quartz, granite, marble, feldspar, clay, ceramics, mica, graphite, silicates, carbonates, sulfates, silicates, phosphates, hydroxides, metal oxides or combinations of two or more of these.

[0194] Specific compounds may be cited as calcium carbonate (CaCO3), silica (SiO2), aluminium hydroxide (AlOH3), magnesium hydroxide.

[0195] According to a particular embodiment, the charge Cl is in powder form.

[0196] The amount of inorganic filler in the (meth)acrylic MCI composition can be up to 300 phr by weight per 100 parts of a liquid (meth)acrylic syrup.

[0197] In a particular embodiment the (meth)acrylic MCI composition comprises between 0.01 phr by weight and 300 phr by weight, more preferably between 20 phr by weight and 300 phr and more preferably still between 30 phr by weight and 200 phr by weight of the inorganic charge Cl for 100 parts of a liquid (meth)acrylic syrup.

[0198] The amount of the inorganic filler Cl, if present, is adjusted in such a way that the (meth)acrylic MCI composition comprising it has a viscosity less than or equal to 30 Pa*s, preferably less than or equal to 25 Pa*s at a temperature of 25 °C.

[0199] In one embodiment the viscosity of the (meth)acrylic MCI composition is 20 Pa*s or less.

[0200] In another embodiment the viscosity of the (meth)acrylic MCI composition is 15 Pa*s or less.

[0201] In yet another embodiment the viscosity of the (meth)acrylic MCI composition comprising an inorganic filler Cl is 0.1 Pa*s or more.

[0202] In yet another embodiment the viscosity of the (meth)acrylic MCI composition comprising an inorganic filler Cl is 0.5 Pa*s or more.

[0203] In a first preferred embodiment the viscosity of the (meth)acrylic MCI composition comprising an inorganic filler Cl is between 0.1 Pa*s and 20 Pa*s.

[0204] In a second preferred embodiment the viscosity of the (meth)acrylic MCI composition comprising an inorganic filler Cl is between 0.5 Pa*s and 15Pa*s.

[0205] In a third preferred embodiment the viscosity of the (meth)acrylic MCI composition comprising an inorganic filler Cl is between 1 Pa*s and 10Pa*s.

[0206] With regard to the fibrous substrate, one can mention several fibers, unidirectional strands or a mat of continuous filaments, fabrics, felts or nonwovens which may be in the form of strips, sheets, braids, strands or pieces. The fibrous material can have different shapes and dimensions, namely one-dimensional, two-dimensional or three-dimensional. A fibrous substrate comprises an assembly of one or more fibers. When the fibers are continuous, their assembly forms fabrics.

[0207] The one-dimensional form corresponds to long linear fibers. The fibers may be discontinuous or continuous. The fibers may be arranged randomly or parallel to each other, in the form of a continuous filament. A fiber is defined by its aspect ratio, which is the ratio between the length and the diameter of the fiber. The fibers used in the present invention are long fibers or continuous fibers. The fibers have an aspect ratio of at least 1000, preferably at least 1500, more preferably at least 2000, advantageously at least 3000, more advantageously at least 5000, even more advantageously at least 6000, even more advantageously at least 7500, and most advantageously at least 10,000.

[0208] The two-dimensional form corresponds to fibrous mats or reinforcements or bundles of non-woven or woven fibers, which may also be braided. Even if the two-dimensional form has a certain thickness and, consequently, in principle a third dimension, it is considered to be two-dimensional according to the present invention.

[0209] The three-dimensional shape corresponds for example to fibrous mats or non-woven reinforcements or bundles of stacked or folded fibers or mixtures thereof, an assembly of the two-dimensional shape in the third dimension.

[0210] The origins of the fibrous material can be natural or synthetic. As natural materials, we can mention plant fibers, wood fibers, animal fibers or mineral fibers.

[0211] Natural fibers include, for example, sisal, jute, hemp, flax, cotton, coconut fibers and banana fibers. Animal fibers include, for example, wool or hair.

[0212] As a synthetic material, mention may be made of polymer fibres selected from thermosetting polymer fibres, thermoplastic polymers or mixtures thereof.

[0213] Polymer fibres may be made of polyamide (aliphatic or aromatic), polyester, polyvinyl alcohol, polyolefins, polyurethanes, polyvinyl chloride, polyethylene, unsaturated polyesters, epoxy resins and vinyl esters.

[0214] Mineral fibers can also be selected from glass fibers, in particular of type E, R or S2, carbon fibers, boron fibers and silica fibers.

[0215] The fibrous substrate of the present invention is selected from plant fibers, wood fibers, animal fibers, mineral fibers, synthetic polymer fibers, glass fibers and carbon fibers, and mixtures thereof.

[0216] Preferably, the fibrous substrate is chosen from mineral fibers. More preferably, the fibrous substrate is chosen from glass fibers or carbon fibers.

[0217] The fibers of the fibrous substrate have a diameter between 0.005 pm and 100 pm, preferably between 1 pm and 50 pm, more preferably between 5 pm and 30 pm and advantageously between 10 pm and 25 pm.

[0218] Preferably, the fibers of the fibrous substrate of the present invention are chosen from continuous fibers (meaning that the aspect ratio does not necessarily apply as for long fibers) for the one-dimensional shape, or from long or continuous fibers for the two- or three-dimensional shape of the fibrous substrate.

[0219] The present invention also relates to a process for preparing an MCI (meth)acrylic composition comprising the following steps:

[0220] i) supply of the following components

[0221] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0222] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI), and

[0223] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single meth)acrylic function, and b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two functions which can undergo polymerization, preferably at least two (meth)acrylic functions

[0224] c) between 0.1 and 5 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, having a glass transition temperature Tg of at least 110 °C)

[0225] ii) mixing components a) to c).

[0226] In a particular embodiment, the present invention relates to a process for preparing a (meth)acrylic MCI composition comprising the following steps:

[0227] i) supply of the following components

[0228] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0229] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI), and

[0230] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0231] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two functions which can undergo polymerization, preferably at least two (meth)acrylic functions

[0232] c) between 0.1 and 5 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, having a glass transition temperature Tg of at least 110 °C

[0233] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0234] ii) mixing components a) to d)

[0235] In another particular embodiment in step i) it is also supplied as compound e) an inorganic filler Cl.

[0236] In another particular embodiment in step i) it is also provided as compound f) a coupling agent.

[0237] The components in the process for preparing an MCI (meth)acrylic composition and its particular embodiments are the same as those defined above and their respective weight proportions.

[0238] Preferably the initiator d) is added as the last component.

[0239] The present invention also relates to the use of the (meth)acrylic MCI composition for impregnating a fibrous substrate, said (meth)acrylic MCI composition comprising:

[0240] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0241] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0242] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0243] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0244] c) of 0.1 to 5 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized into a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0245] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0246] e) possibly an inorganic filler CL

[0247] The present invention also relates to the use of an MCI (meth)acrylic composition to prepare a polymeric (meth)acrylic (MPI) composition, said MCI (meth)acrylic composition comprising:

[0248] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0249] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0250] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0251] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0252] c) between 0.1 and 5 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0253] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0254] e) possibly an inorganic charge Cl.

[0255] Components a) to e) in the use of the (meth)acrylic composition MCI and its particular embodiments are the same as those defined above and their respective weight proportions.

[0256] The present invention further relates to a process for preparing a polymeric composite from an MCI (meth)acrylic composition, said process comprising the following steps:

[0257] i) the impregnation of a fibrous substrate or the mixing of an inorganic filler Cl with a (meth)acrylic MCI composition comprising:

[0258] a) 100 parts of a liquid (meth)acrylic syrup comprising

[0259] al) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI),

[0260] a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function, and

[0261] b) between 0.1 and 9 phr by weight of a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions;

[0262] c) between 0.1 and 10 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, having a glass transition temperature Tg of at least 110 °C;

[0263] d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3);

[0264] ii) the polymerization of the (meth)acrylic composition MCI.

[0265] Components a) to d) in the process for preparing a polymeric composite are the same as those defined above and their respective weight proportions. The different embodiments for the respective ranges of ratios can be combined in any variation concerning preferred or more preferred embodiments or other embodiments.

[0266] The polymerization step takes place at a temperature usually below 110 °C, preferably below 105 °C and more preferably below 100 °C.

[0267] The polymerization step takes place at a temperature usually between 80 °C and 110 °C, preferably between 90 °C and 105 °C and more preferably between 90 °C and 100 °C.

[0268] In a particular embodiment, the polymerization step takes place at a temperature between 95 °C and 100 °C.

[0269] Polymerization takes place in a mold and preferably in a closed mold.

[0270] Once the (meth)acrylic MCI composition has been polymerized, the three components a2) (meth)acrylic monomer (M1), b) the (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions and c) the (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) is different from the (meth)acrylic monomer (M1), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, has a glass transition temperature Tg of at least 110 °C; all together form part of a polymer (P2).

[0271] In the more preferred case where the (meth)acrylic monomer (M3) is an acid (meth)acrylic, the (meth)acrylic (P2) polymer formed could also include anhydride-type motifs.

[0272] After the copolymerization of methacrylic acid as (M3) with (M1) and (M2) to form the main chain of the (meth)acrylic polymer (P2), the carboxylic acid group could react further. Either the carboxylic acid group of the copolymerized methacrylic acid is still present as a side group in the polymer chain, or, for example, two carboxylic acid groups could have formed an anhydride, for example, a type of glutaric anhydride.

[0273] In one embodiment, at least 5% of the polymerized methacrylic acid motifs are transformed into anhydrides.

[0274] In another embodiment, at least 20% of the polymerized methacrylic acid-type motifs are transformed into anhydrides.

[0275] In yet another embodiment, at least 0.5% of the polymerized methacrylic acid-type motifs are transformed into anhydrides.

[0276] Preferably between 0% and 50% of the methacrylic acid type motifs polymerized in the (meth)acrylic polymer (P2) are transformed into anhydrides.

[0277] With regard to the use of the polymer composite material, one can mention automotive and motorsport applications such as, for example, a pressure vessel, ballistic and defense applications, marine applications, railway and transport applications, sports, leisure and recreational applications, art and entertainment applications, aeronautical and aerospace applications, construction and civil engineering applications, housing applications, oil and gas applications, renewable industries applications such as photovoltaic applications and wind energy applications.

[0278] With regard to the use of the mechanical parts made of composite material thus manufactured, mention may be made of automotive applications, transport applications such as buses or trucks, marine applications, railway applications, sports, aeronautical and aerospace applications, photovoltaic applications, computer-related applications, construction and building applications, packaging or storage applications, telecommunications applications and wind energy applications.

[0279] The mechanical part made of composite material is, in particular, a motor vehicle part, a boat part, a bus part, a train part, a sporting article, an airplane or helicopter part, a spacecraft or rocket part, a photovoltaic module part, a construction or building material, a wind turbine part, for example a wind turbine blade beam spar flange, a piece of furniture, a bathroom and / or kitchen appliance, a construction or building part.

[0280] Figures: Figures 1 and 2 represent the relative mass loss of samples (Am in %) as a function of time at 170 °C. The triangle symbol (p) is a comparative example and the diamond or square symbols ( and ) are examples according to the invention formed from syrups S2 and S3 respectively. [Processes]

[0281] Viscosity is measured at a shear rate of 1s 1 at 25 °C.

[0282] The glass transition temperature Tg is measured by differential calorimetry dynamic (differential scanning calorimetry, DSC) using a TA Q2000 device, according to ISO 11357-2 / 2013 at a heating rate of 20 K / min.

[0283] The molecular weight is measured by size exclusion chromatography (SEC). The chromatography column is calibrated with PMMA references having a molecular weight between 402 g / mol and 1,900,000 g / mol. The average molecular weight is expressed in g / mol for the number-average molecular weight (Mn) and the weight-average molecular weight (Mw), respectively. The concentration used for the measurement is 1 g / L. Examples

[0284] A liquid (meth)acrylic syrup S0 is prepared by dissolving 20 parts by weight PMMA (BS520, an MMA copolymer comprising ethyl acrylate as an Altuglas comonomer) as (PI) in 80 parts by weight of methyl methacrylate as (Ml), which is stabilized with MEHQ (hydroquinone monomethyl ether). Liquid (meth)acrylic syrup S0 is used to prepare the composition of the comparative examples and the examples of the invention by adding additional compounds.

[0285] Comparative Example 1: A syrup SI is prepared from 100 parts by weight of syrup S0 by adding 1 part by weight of 1,4-butanediol dimethacrylate (Sartomer SR214), 1 part by weight of triethylene glycol dimethacrylate (Sartomer SR205), 0.3 parts by weight of coupling agent Geniosil® GF31 (Wacker). Then, 2 parts by weight of 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane (AKZO NOBEL TRIGONOX® 141) are added.

[0286] Example 1: a syrup S2 is prepared from syrup S0 by adding to 100 parts by weight of syrup S0 the following additional compounds: 4 parts by weight of ethoxylated bisphenol A dimethacrylate as (M2) (SR348 from Sartomer), 1 part by weight of methacrylic acid as (M3), 0.3 parts by weight of coupling agent Geniosil® Gf31 (from Wacker), 0.1 part by weight of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 770DF from BASF), 0.1 part by weight of 3,5-bis(l,l-dimethylethyl)-4-hydroxy-, l,l'-(thiodi-2,l-ethanediyl) ester (IRGANOX 1035 from BASF), 0.1 part of Vultac3. Then 2 parts by weight of tert-amyl-peroxy-l-methoxycyclohexane are added.

[0287] Example 2: A syrup S3 is prepared from syrup S0 by adding to 100 parts by weight of the syrup 5 parts of 1,4-butanediol dimethacrylate (SR214 from Sartomer), 5 parts by weight of methacrylic acid as (M3), 0.3 parts by weight of coupling agent Geniosil® Gf31 (from Wacker), 0.1 parts by weight of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 770DF from BASF), 0.1 parts by weight of 3,5-bis(l,l-dimethylethyl)-4-hydroxy-, l,l'-(thiodi-2,l-ethanediyl) ester (IRGANOX 1035 from BASF), 0.1 part of Vultac3. Then 2 parts by weight of tert-amyl-peroxy-l-methoxycyclohexane are added.

[0288] Each of the respective SI to S3 syrups is mixed with 61 wt% silica, the two together totaling 100 wt%. Finally, 2 wt% of each respective initiator relative to the syrup portion are added. The compositions are mixed to obtain a homogeneous composition. The respective compositions are vacuum-sealed for degassing and transferred into a mold. The mold is heated to a temperature of 96 °C.

[0289] Three molded materials based on the respective syrups SI, S2 and S3 are obtained.

[0290] Thermal aging is evaluated on each of the three molded compounds. For this purpose, a sample of approximately 20 g is cut from each molded compound. The samples are placed in a ventilated oven at 170 °C and weighed periodically over a period of approximately several hundred hours.

[0291] Thermal aging is expressed as a relative mass loss Am in % with respect to the mass of the initial sample.

[0292] This relative mass loss is shown in Figures 1 and 2 for the material obtained from the polymerization of the three respective syrups. Figures 1 and 2 show that the relative mass loss for Example 1 (rhombus) and Example 2 (square) according to the invention is less than that of the comparative example (triangle), which indicates better thermal resistance.

Claims

Demands

1. (Meth)acrylic MCI composition comprising, a) 100 parts of a liquid (meth)acrylic syrup comprising a1) between 10% by weight and 50% by weight of a (meth)acrylic polymer (PI), and a2) between 50% by weight and 90% by weight of a (meth)acrylic monomer (M1) comprising a single (meth)acrylic function, and b) between 0.1 and 5 phr by weight of a (meth)acrylic monomer (M2) comprising at least two functions which can undergo polymerization preferably at least two (meth)acrylic functions; (c) between 0.1 and 2 phr by weight of a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function and the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (Ml), said (meth)acrylic monomer (M3), if polymerized as a homopolymer, having a glass transition temperature Tg of at least 110 °C measured according to ISO 11357-2:2020;(e) optionally an inorganic filler Cl or fibres or fibrous material, characterized in that the (meth)acrylic monomer (M2) is selected from ethoxylated bisphenol A diacrylate (10); ethoxylated bisphenol A dimethacrylate (2); ethoxylated bisphenol A diacrylate (3); ethoxylated bisphenol A dimethacrylate (3); ethoxylated bisphenol A diacrylate (4); ethoxylated bisphenol A dimethacrylate (4); ethoxylated bisphenol A dimethacrylate; ethoxylated bisphenol A dimethacrylate (10) and mixtures thereof.

2. (Method)acrylic MCI composition according to claim 1, characterized in that the composition further comprises d) between 0.1 phr and 5 phr of an initiator to start the polymerization of (meth)acrylic monomers (M1), (M2) and (M3).

3. MCI (meth)acrylic composition according to claim 1 or 2, characterized in that the composition further comprises e) an inorganic filler Cl or fibers or fibrous material.

4. MCI (meth)acrylic composition according to any one of claims 1 to 3, characterized in that the monomer (Metha)acrylic (M3) is selected from methacrylic acid, isobornyl methacrylate, tert-butyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl methacrylate and mixtures thereof.

5. (Metha)acrylic MCI composition according to any one of claims 1 to 3, characterized in that the (meth)acrylic monomer (M3) is selected from methacrylic acid.

6. (Method)acrylic MCI composition according to any one of claims 1 to 5, characterized in that the (meth)acrylic monomer (Ml) is selected from hydroxyalkyl acrylic monomers, hydroxyalkyl methacrylic monomers, alkyl acrylic monomers, alkyl methacrylic monomers and corresponding mixtures, the alkyl group containing from 1 to 22 linear, branched or cyclic carbon atoms; the alkyl group preferably containing from 1 to 12 linear, branched or cyclic carbon atoms.

7. MCI (meth)acrylic composition according to any one of claims 2 to 6, characterized in that the initiator d) is in the form of a peroxide-type compound which is liquid in a temperature range of 0 °C to 50 °C.

8. MCI (meth)acrylic composition according to any one of claims 2 to 7, characterized in that the initiator d) has a half-life temperature at 1 hour, which is greater than 70 °C.

9. MCI (meth)acrylic composition according to any one of claims 2 to 7, characterized in that the initiator d) has a half-life temperature at 1 hour and 1013 mbars of between 70 °C and 140 °C, more preferably between 80 °C and 135 °C and even more preferably between 90 °C and 130 °C and most preferably between 95 °C and 125 °C.

10. (Method)acrylic MCI composition according to any one of claims 2 to 9, characterized in that the initiator d) is selected from tert-amyl peroxypivalate, tert-butyl peroxypivalate, bis(3,5,5-trimethylhexanoyl peroxide), 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethyl acetate, tert-butyl peroxyisobutyrate, tert-amylperoxy-1- methoxycyclohexane, 1-methoxy-1-t-butylperoxycyclohexane, 1-methoxy-lt-amylperoxy-3,3,5-trimethylcyclohexane, 1-methoxy-lt-butylperoxy-3,3,5-trimethylcyclohexane, 1-ethoxy-lt-amylperoxycyclohexane, 1-ethoxy-1-t-butylperoxycyclohexane, 1 -ethoxy-1 -t-butyl-3,3,5-peroxycyclohexane, 1,1 -d\(lerl-amylperoxy)cyclohexane, l,l-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1 -di ( / e / 7-buty Ipcroxy )cyclohcxanc, peroxy-2-ethylhexylcarbonate tert-amyl, peroxy-2-ethylhexylcarbonate tert-butyl, tert-amyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-amyl peroxyacetate, tert-butyl peroxyacetate, 2,2-di(tert-butylperoxy)butane, 2,2-di(tert-amylperoxy)butane, tert-amyl peroxybenzoate, tert-butyl peroxybenzoate, butyl 4,4-di(tert-butylperoxy)valerate, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and mixtures thereof.

11. MCI (meth)acrylic composition according to any one of claims 2 to 9, characterized in that the initiator d) is selected from tert-amylperoxy-l-methoxycyclohexane, 1-methoxy-1-t-butylperoxycyclohexane, 1-methoxy-lt-amylperoxy-3,3,5-trimethylcyclohexane, 1-methoxy-lt-butylperoxy-3,3,5-trimethylcyclohexane, 1-ethoxy-1-t-amylperoxycyclohexane, 1-ethoxy-1-t-butylperoxycyclohexane, 1-ethoxy-1-t-butyl-3,3,5-peroxycyclohexane and mixtures thereof.

12. MCI (meth)acrylic composition according to any one of claims 1 to 11, characterized in that the MCI (meth)acrylic composition does not comprise a polymerization activator.

13. MCI (meth)acrylic composition according to any one of claims 1 to 12, characterized in that the MCI (meth)acrylic composition comprises between 0.5 and 2 phr by weight of the (meth)acrylic monomer (M3).

14. MCI (meth)acrylic composition according to any one of claims 1 to 13, characterized in that the liquid (meth)acrylic syrup comprises a) between 10% by weight and 30% by weight of a (meth)acrylic polymer (PI), and a2) between 70% by weight and 90% by weight of a (meth)acrylic monomer (Ml) comprising a single (meth)acrylic function.

15. MCI (meth)acrylic composition according to any one of claims 1 to 14, characterized in that the (meth)acrylic monomer (M2) is present in an amount between 0.5 and 5 phr per 100 parts of a liquid (meth)acrylic syrup.

16. A process for preparing a (meth)acrylic MCI composition according to any one of claims 1 to 15, said process comprising the following steps: i) supplying the following components: a) a (meth)acrylic polymer (PI) and a (meth)acrylic monomer (M1) comprising a single (meth)acrylic function; b) a (meth)acrylic monomer (M2) comprising at least two (meth)acrylic functions; c) a (meth)acrylic monomer (M3) comprising a single (meth)acrylic function, the (meth)acrylic monomer (M3) being different from the (meth)acrylic monomer (M1); d) optionally an initiator for starting the polymerization of the (meth)acrylic monomers (M1), (M2), and (M3); e) optionally an inorganic filler Cl or a fibrous material; ii) mixing components a) with c) or a) with d) or a) with e) in the respective reports.

17. Use of the (meth)acrylic MCI composition according to any one of claims 1 to 15 or prepared by the process according to claim 16, to impregnate a fibrous substrate.

18. Use of the (meth)acrylic MCI composition according to any one of claims 1 to 15 or prepared by the process according to claim 16, to prepare a (meth)acrylic polymeric composition.

19. A process for preparing a polymeric composite from an MCI (meth)acrylic composition according to any one of claims 1 to 15, said process comprising the following steps: i) impregnating a fibrous substrate or mixing an inorganic filler Cl with said MCI (meth)acrylic composition; ii) polymerizing the MCI (meth)acrylic composition.

20.

21.

22.

23. A process for preparing a polymeric composite according to claim 19, characterized in that the polymerization step takes place at a temperature between 80 °C and 110 °C. A method for preparing a polymeric composite according to any one of claims 19 to 20, characterized in that the polymerization takes place in a mold and preferably in a closed mold. Polymeric composite material obtained from a process according to claim 19 or 20 or 21. Use of the composite material according to claim 22 in automotive and motorsport applications such as, for example, pressure vessels, ballistic and defense applications, marine applications, railway and transport applications, sports, leisure and recreational applications, art and entertainment applications, aeronautical and aerospace applications, construction and civil engineering applications, oil and gas applications, renewable energy applications such as photovoltaic applications and wind energy applications.