阅读说明：本技术 包含蜡化合物的液体组合物、其聚合方法、用途以及在组合物聚合后获得的材料或组合物 (Liquid composition comprising wax compounds, method for polymerization thereof, use and material or composition obtained after polymerization of the composition ) 是由 P·热拉尔 于 2020-03-11 设计创作，主要内容包括：本发明涉及包含单体、(甲基)丙烯酸类聚合物和蜡化合物的液体组合物。特别地,本发明涉及包含单体、(甲基)丙烯酸类聚合物和蜡化合物的液体组合物。该液体组合物可以用作浆液,且尤其是用作浸渍纤维或纤维材料的浆液。还涉及在液体组合物聚合之后获得的热塑性材料。本发明还涉及制造此类液体组合物的方法。本发明还涉及用所述液体组合物浸渍长纤维或连续纤维的纤维基材的方法。本发明还涉及用所述液体组合物浸渍的纤维基材,所述纤维基材可用于制造复合材料零件。本发明还涉及制造由复合材料所制成的机械零件或结构元件的方法,以及由经由使用此类液体组合物的方法获得的复合材料所制成的机械零件或结构元件。(The present invention relates to a liquid composition comprising monomers, (meth) acrylic polymers and wax compounds. In particular, the present invention relates to a liquid composition comprising monomers, (meth) acrylic polymers and wax compounds. The liquid composition may be used as a slurry, and in particular as a slurry for impregnating fibres or fibrous materials. It also relates to the thermoplastic material obtained after polymerization of the liquid composition. The invention also relates to a method of making such liquid compositions. The invention also relates to a method for impregnating a fibrous substrate of long or continuous fibres with said liquid composition. The invention also relates to a fibrous substrate impregnated with said liquid composition, said fibrous substrate being useful for the manufacture of composite parts. The invention also relates to a method for manufacturing a mechanical part or structural element made of a composite material, and to a mechanical part or structural element made of a composite material obtained by a method using such a liquid composition.)

1. A liquid composition LCl, comprising:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition has a dynamic viscosity at 25 ℃ of between 10 and 10000 mPas.

2. The liquid composition LCl according to claim 1, characterized in that the amount of the wax compound (W) in the composition is between 0.1 phr and 2 phr, relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

3. The liquid composition LCl according to claim 1, characterized in that the amount of the wax compound (W) in the composition is between 0.55 phr and 1.3 phr, relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

4. The liquid composition LCl according to claim 1, 2 or 3, characterized in that the density of the wax compound (W) is less than the density of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1) together.

5. The liquid composition LCl according to claim 1, 2 or 3, characterized in that the wax compound (W) has a density of less than 1.1 g/cm³。

6. The liquid composition LCl according to claim 1, 2 or 3, characterized in that the wax compound (W) has a density of 0.7 g/cm³And 1.1 g/cm³In the meantime.

7. The liquid composition LCl according to claim 1, 2 or 3, characterized in that the wax compound (W) has a density of 0.85 g/cm³And 0.98 g/cm³In the meantime.

8. The liquid composition LCl according to any one of claims 1 to 7, characterized in that the liquid composition additionally comprises d) an initiator (Ini).

9. The liquid composition LCl according to claim 7, characterized in that the amount of the initiator (Ini) in the composition is between 0.75 phr and 8 phr and advantageously at most between 1 phr and 5 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

10. The liquid composition LCl according to any one of claims 8 to 9, characterized in that the initiator (Ini) is selected from diisobutyryl peroxide, cumyl peroxyneodecanoate, di (3-methoxybutyl) peroxydicarbonate, 1,3, 3-tetramethylbutyl peroxyneodecanoate, cumyl peroxyneoheptanoate, di-n-propyl peroxydicarbonate, tert-amyl peroxyneodecanoate, di-sec-butyl peroxydicarbonate, diisopropyl peroxydicarbonate, di (4-tert-butylcyclohexyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, tert-amyl peroxyneodecanoate, tert-butyl peroxyneodecanoate, di-n-butyl peroxydicarbonate, dicetyl peroxydicarbonate, dimyristyl peroxydicarbonate, pivalic-1, 1,3, 3-tetramethylbutyl ester, tert-butyl peroxypivalate, tert-amyl peroxypivalate, tert-butyl peroxypivalate, bis- (3,5, 5-trimethylhexanoyl) peroxide, dilauroyl peroxide, didecanoyl peroxide, 2, 5-dimethyl-2, 5-bis (2-ethylhexanoylperoxide) -hexane, 1,3, 3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethylacetate, tert-butyl peroxyisobutyrate, 1-bis (tert-butylperoxy) -3,3, 5-trimethylcyclohexane, 1, 1-bis (t-amylperoxy) -cyclohexane, 1-bis (t-butylperoxy) -cyclohexane, t-amyl peroxy-2-ethylhexyl carbonate, t-amyl peroxyacetate, t-butyl peroxy-3, 5, 5-trimethylhexanoate, 2-bis (t-butylperoxy) -butane, t-butyl peroxyisopropylcarbonate, t-butyl peroxy-2-ethylhexyl carbonate, t-amyl peroxybenzoate, t-butyl peroxyacetate, butyl 4, 4-bis (t-butylperoxy) valerate, t-butyl peroxybenzoate, di-t-amyl peroxide, dicumyl peroxide, bis (2-t-butyl-peroxyisopropyl) -benzene, 2, 5-dimethyl-2, 5-bis (t-butylperoxy) -hexane, hexane, Tert-butylcumyl peroxide, 2, 5-dimethyl-2, 5-di (tert-butylperoxy) hex-3-yne, di-tert-butyl peroxide, 3,6, 9-triethyl-3, 6, 9-trimethyl-1, 4, 7-triperoxonane, 2' -azobis-isobutyronitrile (AIBN), 2' -azobis- (2-methylbutyronitrile), azobisisobutyramide, 2' -azobis (2, 4-dimethylvaleronitrile), 1' -azobis (hexahydrobenzonitrile) or 4,4' -azobis (4-cyanovaleric acid), and mixtures thereof.

11. The liquid composition LCl according to any one of claims 1 to 10, characterized in that the wax compound (W) has a freezing point between 15 ℃ and 85 ℃.

12. The liquid composition LCl according to any one of claims 1 to 10, characterized in that the wax compound (W) has a freezing point between 25 ℃ and 60 ℃.

13. The liquid composition LCl according to any one of claims 1 to 12, characterized in that the (meth) acrylic polymer (P1) comprises at least 50 wt.% of Methyl Methacrylate (MMA).

14. The liquid composition LCl according to any one of claims 1 to 13, characterized in that the (meth) acrylic monomer is selected from the group consisting of methyl methacrylate, 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.

15. The liquid composition LCl according to any one of claims 1 to 14, characterized in that 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 (M1) is a mixture of methyl methacrylate and optionally at least one other monomer.

16. The liquid composition LCl according to any one of claims 1 to 15, characterized in that the liquid composition LC1 has a dynamic viscosity at 25 ℃ of between 25 and 1000 mPa s.

17. The liquid composition LCl according to any one of claims 1 to 15, characterized in that the liquid composition LC1 has a dynamic viscosity of between 30 and 1000 mPa-s measured with a rheometer at 25 ℃.

18. The liquid composition LCl according to any one of claims 1 to 17, characterized in that the liquid composition LC1 comprises between 0.01 and 10 phr by weight of monomer (M2), relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1), the (meth) acrylic monomer (M2) comprising at least two (meth) acrylic functionalities.

19. The liquid composition LCl according to claim 18, characterized in that the (meth) acrylic monomer (M2) is selected from ethylene glycol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, 1, 4-butanediol diacrylate, 1, 3-butanediol dimethacrylate or mixtures thereof.

20. The liquid composition LCl according to any one of claims 1 to 19, characterized in that the weight average molecular mass of the (meth) acrylic polymer (P1) is greater than 50000 g/mol, and preferably greater than 100000 g/mol.

21. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the liquid composition LCl or (meth) acrylic syrup has one or more (meth) acrylic monomers (Ml) present in a proportion of between 40 and 90% by weight, and preferably between 45 and 85% by weight of the composition comprising one or more (meth) acrylic monomers (M1) and (meth) acrylic polymer (P1).

22. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the (meth) acrylic monomer (Ml) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 60% and 85% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

23. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the (meth) acrylic monomer (Ml) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 65% and 85% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

24. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the (meth) acrylic polymer (Pl) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 10 and 60% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

25. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the (meth) acrylic polymer (Pl) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 15 and 40% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

26. The liquid composition LCl according to any one of claims 1 to 20, characterized in that the (meth) acrylic polymer (Pl) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 15 and 35% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

27. A method of making the liquid composition LCl of any one of claims 1-26, the method comprising the steps of:

i) preparing a mixture of a (meth) acrylic polymer (P1) and a (meth) acrylic monomer (M1);

ii) adding a wax compound (W) to the mixture prepared in the previous step.

28. The method according to claim 27, characterized in that the (meth) acrylic polymer (Pl) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 15 and 40% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1), and the (meth) acrylic monomer (Ml) in the liquid composition LCl or (meth) acrylic syrup is present in a proportion of between 60 and 85% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

29. The method according to claim 27, characterized in that the (meth) acrylic polymer (Pl) in the liquid composition LCl or (meth) acrylic slurry is present in a proportion of between 15 and 35% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1), and the (meth) acrylic monomer (Ml) in the liquid composition LCl or (meth) acrylic slurry is present in a proportion of between 65 and 85% by weight of the composition comprising (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

30. The process according to claim 27, characterized in that an initiator (Ini) is added to the liquid composition LCl.

31. The method according to claim 30, characterized in that the temperature T is at a temperature lower than 50 ℃, more preferably lower than 40 ℃, advantageously lower than 30 ℃ and more advantageously lower than 25 ℃_addThe initiator (Ini) is added.

32. The method according to claim 27, characterized in that the freezing point of the wax compound (W) is between 25 ℃ and 60 ℃.

33. Use of the liquid composition LC1 according to any one of claims 1 to 26 or the liquid composition LC1 prepared according to the method of any one of claims 27 to 32 for the manufacture of a thermoplastic part or for the manufacture of a composite part.

34. Use of the liquid composition LC1 according to any one of claims 1 to 26 or the liquid composition LC1 prepared according to the method of any one of claims 27 to 32 for impregnating a fiber or fibrous substrate.

35. Use of the liquid composition LC1 according to any one of claims 1 to 26 for the manufacture of a thermoplastic part or for the manufacture of a composite part.

36. A method of making a thermoplastic part by a method comprising the steps of:

i) preparation of a liquid mixture of (meth) acrylic Polymer (P1) and (meth) acrylic monomer (M1)

ii) adding a wax compound (W) to the mixture prepared in the previous step,

iii) placing the liquid (meth) acrylic composition prepared in i) and ii) in a means for polymerization, said composition being characterized in that it additionally comprises:

d) an initiator (Ini);

the liquid (meth) acrylic slurry according to any one of claims 1 to 10, having a dynamic viscosity at 25 ℃ of between 10 mPas and 10000 mPas,

iv) polymerization.

37. A method of making a thermoplastic composite part by a method comprising the steps of:

i) preparation of a liquid mixture of (meth) acrylic Polymer (P1) and (meth) acrylic monomer (M1)

ii) adding a wax compound (W) to the mixture prepared in the previous step,

iii) placing said liquid (meth) acrylic composition prepared in i) and ii) in a means for polymerization, said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) an initiator (Ini);

the liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPas and 10000 mPas,

iv) polymerization.

38. A method of making a thermoplastic composite part by a method comprising the steps of:

i) preparing a mixture of a (meth) acrylic polymer (P1) and a (meth) acrylic monomer (M1) and a wax compound (W),

ii) adding an initiator (Ini) to the mixture prepared in the preceding step,

iii) impregnating the fiber or fibrous substrate with the liquid (meth) acrylic composition prepared in i) and ii), said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) an initiator (Ini);

the liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPas and 10000 mPas,

iv) polymerization.

39. A method of manufacturing a composite part by a method comprising the steps of:

i) preparing a mixture of the (meth) acrylic polymer (P1), the (meth) acrylic monomer (M1) and the wax compound (W),

ii) adding an initiator (Ini) to the mixture prepared in the preceding step,

iii) impregnating the fibres or fibrous substrate with the liquid composition prepared in i) and ii), said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) two initiators (Ini 1) and (Ini 2);

the liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPas and 10000 mPas,

iv) polymerization.

40. The method of claims 36-3915, performed by open die, pultrusion, hand lay-up, and filament winding.

41. The process according to any one of claims 36 to 40, characterized in that said polymerization step is carried out at a temperature between 40 ℃ and 140 ℃.

42. A method according to any one of claims 36 to 41, characterized in that it additionally comprises a post-forming step.

43. A method according to any one of claims 36 to 41, characterized in that it additionally comprises a step of welding or gluing or laminating.

44. Polymer composite comprising a thermoplastic (meth) acrylic matrix and a fibrous substrate for reinforcement, wherein the fibrous substrate consists of long fibers having an aspect ratio of at least 1000, characterized in that the thermoplastic (meth) acrylic matrix is obtained after polymerization of the liquid composition LC1, the fibrous substrate being pre-impregnated with the liquid composition LC according to any one of claims 1 to 10.

45. A mechanical part or structural element made of a composite material as claimed in claim 44 or obtained by a method as claimed in any one of claims 36 to 43.

46. The part of claim 45, which is a motor vehicle part, a watercraft part, a train part, a sporting article, an aircraft or helicopter part, a spacecraft or rocket part, an optoelectronic component part, a material for construction or construction such as composite rebars, dowels and stirrups for civil engineering and high-rise buildings, a spar cap of a wind turbine part such as a spar of a wind turbine blade, a furniture part, a construction or building part, a telephone or cell phone part, a computer or television part, a printer or copier part.

Technical Field

The present invention relates to a liquid composition comprising monomers, (meth) acrylic polymers and wax compounds.

In particular, the present invention relates to a liquid composition comprising monomers, (meth) acrylic polymers and wax compounds. The liquid composition may be used as a slurry (syrup), and in particular as a slurry for impregnating fibres or fibrous materials. It also relates to the thermoplastic material obtained after polymerization of the liquid composition. The invention also relates to a method of making such liquid compositions. The invention also relates to a method for impregnating a fibrous substrate of long or continuous fibres with said liquid composition. The invention also relates to a fibrous substrate impregnated with said liquid composition, said fibrous substrate being useful for the manufacture of composite parts.

The invention also relates to a method for manufacturing a mechanical part or structural element made of a composite material, and to a mechanical part or structural element made of a composite material obtained by a method using such a liquid composition.

Prior Art

Thermoplastic polymers are today materials widely used in several fields and applications, where they are part of mechanical parts, for example in the construction, aerospace, automotive or railway field.

The mechanical parts, which have to withstand high stresses during their use, are widely manufactured from composite materials. A composite material is a macroscopic combination of two or more immiscible materials. The composite material consists of at least one material forming a matrix (i.e. a continuous phase ensuring the cohesion of the structure) and a reinforcing material.

The purpose of using a composite material is to achieve a performance quality that cannot be obtained from each of its components when used alone. Composite materials are therefore widely used in a number of industrial fields, such as construction, automotive, aeronautics, transportation, leisure, electronics and sports, due to, inter alia, their better mechanical properties (higher tensile strength, higher tensile modulus, higher fracture toughness) and their low density, compared to homogeneous materials.

To achieve thermoforming and recycling, it is preferred to also use thermoplastic polymers in the composite material, rather than thermoset polymers.

Thermoplastic polymers consist of linear or branched polymers which are not usually crosslinked. The thermoplastic polymer is heated to mix the ingredients necessary to make the composite and cooled to coagulate the final form. A problem with these molten thermoplastic polymers is that their viscosity in the molten state is very high in order to uniformly impregnate, for example, a fibrous substrate. Wetting or proper impregnation of the fibers by the thermoplastic polymer can only be achieved if the thermoplastic resin has sufficient flowability. In order to provide the thermoplastic polymer with a low viscosity or sufficient flowability, the chain length or molecular mass should be reduced. However, too low a molecular weight has a negative effect on the properties of the composite material and on the mechanical or structural parts, in particular their mechanical properties (e.g. deformation modulus).

To prepare thermoplastic polymer-based polymer composites, a reinforcing material, such as a fibrous substrate, is impregnated with a thermoplastic polymer resin, commonly referred to as a "slurry". Upon polymerization, the thermoplastic polymer slurry forms the matrix of the composite.

Another way to reduce the viscosity of the thermoplastic polymer in an important way is to increase the temperature. Consequently, the continuous operating temperatures are relatively high, above 200 ℃, increasing the economic cost of composite materials and mechanical or structural parts due to the high energy costs. Furthermore, if the temperature is too high, the thermoplastic polymer tends to degrade, this is especially the case for semi-crystalline thermoplastic polymers having a high melting point such as, for example, polyamides like PA 6.6, Polyethersulfone (PES), Polyetherimide (PEI), Polyetheretherketone (PEEK) or polyphenylene sulfide (PPS). This thermally induced degradation produces a molecular weight reduction of the polymer matrix on the fibrous substrate (important for the adhesion of composite materials and mechanical or structural parts).

Another method for impregnating a fibrous substrate is to dissolve the thermoplastic polymer in an organic solvent. However, this process requires a large amount of solvent which must be evaporated. The use of large amounts of solvents presents environmental problems in terms of energy and pollution.

Yet another method for impregnating a fibrous substrate is to use monomers for impregnation and to polymerize to form a thermoplastic polymer after impregnation. However, such processes typically use monomers that can partially evaporate or have an undesirable odor. This is particularly problematic when impregnation is carried out in an open impregnation process in contact with the environment or air. In addition, the use of certain monomers in open environments also presents environmental problems.

In impregnation, the viscosity of the impregnation slurry must be controlled and varied in the preparation of the polymer composite so as not to be too fluid or too viscous to properly impregnate the individual fibers of the fibrous substrate. When partially wetted, depending on whether the slurry is too fluid or too viscous, there are "bare" areas, i.e., unimpregnated areas, and areas where polymer droplets are formed on the fibers (which are responsible for the generation of bubbles) respectively. These "bare" areas and these air bubbles cause defects in the final composite material, which is especially responsible for the loss of mechanical strength of the final composite material. Furthermore, the evaporation of the monomers also has an effect on the viscosity.

It is an object of the present invention to propose a liquid composition comprising (meth) acrylic monomers with reduced evaporation of the (meth) acrylic monomers.

Liquid compositions or slurries comprising (meth) acrylic monomers and (meth) acrylic polymers are described in WO 2013/056845 and WO 2014/013028. Neither document uses wax compounds and when the composition is used in an open mold or in the open air, a part of the (meth) acrylic monomer evaporates and changes the weight ratio and viscosity in the composition.

Document WO 2015/110534 discloses liquid (meth) acrylic slurries. The slurry contains specific (meth) acrylic monomers with high boiling points and low vapor pressures to avoid evaporation thereof. Impregnation processes require these specific monomers, which can be more expensive and reduce the choice of monomers in the process.

None of these documents show that the incorporation of wax compounds into liquid compositions significantly reduces the evaporation of monomers.

[ problem of the invention]

It is therefore an object of the present invention to ameliorate at least one of the disadvantages of the prior art.

It is an object of the present invention to propose a liquid composition comprising (meth) acrylic monomers with reduced evaporation of the (meth) acrylic monomers. Reduced evaporation is understood to mean that less than 20% by weight of the (meth) acrylic monomer evaporates, preferably less than 10% by weight, even more preferably less than 5% by weight and advantageously less than 2% by weight. Evaporation was checked at 23 ℃ for 20 minutes duration.

It is also an object of the present invention to have a liquid composition comprising (meth) acrylic monomers, (meth) acrylic polymers, which has reduced evaporation of (meth) acrylic monomers and can be polymerized fast and to good conversion. Good conversion is understood to mean that at least 95% of the monomers have polymerized.

It is also an object of the present invention to have a process for polymerizing a liquid composition comprising (meth) acrylic monomers, (meth) acrylic polymers to good conversion while having reduced evaporation of (meth) acrylic monomers.

It is yet another object of the present invention to use a liquid composition comprising (meth) acrylic monomers, (meth) acrylic polymers for impregnating a fibrous substrate with reduced evaporation of (meth) acrylic monomers.

Brief description of the invention

It has been surprisingly found that liquid composition LCl comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 has a dynamic viscosity at 25 ℃ between 10 and 10000 mPa s, resulting in a liquid composition with reduced evaporation of (meth) acrylic monomer (M1) compared to a composition not comprising the wax compound (W).

It has also been found that liquid composition LCl comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 having a dynamic viscosity at 25 ℃ between 10 and 10000 mPa s can be used to produce a thermoplastic composite polymer composition after polymerization of the (meth) acrylic monomer (M1), which has a good conversion.

It has also been found that a liquid composition LC1 or a liquid (meth) acrylic composition LC1 for impregnating a fibrous substrate consisting of long or continuous fibers, said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 or liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s; can be used as a liquid composition for impregnation with reduced evaporation of the (meth) acrylic monomer (M1) compared to a composition not comprising the wax compound (W).

It has furthermore surprisingly been found that a method for impregnating a fibrous substrate comprises the following steps:

i) impregnating a fibrous substrate with such a liquid composition LC1 or a (meth) acrylic slurry comprising

a) A (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

an impregnated fiber substrate having reduced evaporation of the (meth) acrylic monomer (M1) can be obtained as compared with a composition not containing the wax compound (W).

It has furthermore surprisingly been found that a method for manufacturing a composite material part comprises the following steps:

i) impregnating a fibrous substrate with such a liquid composition LC1 or a (meth) acrylic slurry comprising

a) A (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

ii) polymerization

An impregnated fiber substrate having reduced evaporation of the (meth) acrylic monomer (M1) can be obtained as compared with a composition not containing the wax compound (W).

Detailed Description

According to a first aspect, the present invention relates to a liquid composition LC1, said liquid composition LC1 comprising:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 has a dynamic viscosity at 25 ℃ of between 10 and 10000 mPa s.

According to a second aspect, the invention relates to a liquid composition LC1 for impregnating a fibrous substrate, said fibrous substrate consisting of long fibres, and said liquid composition LC1 being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 or liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s.

According to a third aspect, the present invention relates to a process for the preparation of a liquid composition LC1, said liquid composition LC1 being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 or liquid (meth) acrylic syrup having a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s, prepared by a process comprising the steps of:

i) preparation of a liquid mixture of (meth) acrylic Polymer (P1) and (meth) acrylic monomer (M1)

ii) adding the wax compound (W) to the mixture prepared in the previous step.

According to a fourth aspect, the present invention relates to the use of a liquid composition LC1 for impregnating a fibrous substrate, said fibrous substrate consisting of long fibres, and said liquid composition LC1 being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 or liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s.

According to a fifth aspect, the present invention relates to the use of a liquid composition LC1 for the manufacture of thermoplastic parts or for the manufacture of composite parts, and said liquid composition LC1 is characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1), and

c) a wax compound (W);

the liquid composition LC1 or liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s.

According to a sixth aspect, the present invention relates to a method of manufacturing a thermoplastic composite part by a method comprising the steps of:

i) preparing a liquid mixture of a (meth) acrylic polymer (P1) and a (meth) acrylic monomer (M1),

ii) adding a wax compound (W) to the mixture prepared in the previous step,

iii) placing the liquid (meth) acrylic composition or liquid composition LC1 prepared in i) and ii) in a tool for polymerization, said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) an initiator (Ini);

the liquid composition LC1 or liquid (meth) acrylic syrup has a dynamic viscosity at 25 ℃ of between 10 mPa s and 10000 mPa s,

iv) polymerization.

According to a seventh aspect, the invention relates to a method of manufacturing a composite part by a method comprising the steps of:

i) preparing a mixture of a (meth) acrylic polymer (P1) and a (meth) acrylic monomer (M1) and a wax compound (W),

ii) adding an initiator (Ini) to the mixture prepared in the preceding step,

iii) impregnating the fiber or fibrous substrate with the liquid (meth) acrylic composition or liquid composition LC1 prepared in i) and ii), said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) an initiator (Ini));

said liquid (meth) acrylic syrup or liquid composition LC1 having a dynamic viscosity at 25 ℃ of between 10 and 10000 mPas,

iv) polymerization.

The term "fibrous substrate" as used herein refers to a plurality of fibers, unidirectional rovings (rovings) or continuous filament mats, fabrics, felts or nonwovens, which may be in the form of tapes, loops (laps), braids (braids), locks (locks) or sheets.

The term "(meth) acrylic" as used refers to any type of acrylic or methacrylic monomer.

The term "PMMA" as used refers to homopolymers and copolymers of Methyl Methacrylate (MMA), the weight ratio of MMA in PMMA being at least 70% by weight with respect to the MMA copolymer.

The term "monomer" as used herein refers to a molecule that can undergo polymerization.

The term "polymerization" as used herein refers to a process of converting a monomer or mixture of monomers into a polymer.

The term "thermoplastic polymer" as used herein refers to a polymer that becomes liquid or more fluid or less viscous, or becomes soft when heated, and can assume a new shape upon the application of heat and pressure. This also applies to slightly crosslinked thermoplastic polymers that can be thermoformed when heated above the softening temperature.

The term "polymer composite" as used herein refers to a multicomponent material comprising several distinct domains, wherein at least one type of domain is a continuous phase, and wherein at least one component is a polymer.

The term "initiator" as used herein refers to a compound that can initiate polymerization of one or more monomers.

The abbreviation "phr" refers to parts by weight per hundred parts of the composition. For example, 1 phr of a compound in a composition means that 1 kg of the compound is added to 100 kg of the composition.

The abbreviation "ppm" refers to parts by weight per million parts of the composition. For example, 1000 ppm of a compound in a composition means that 0.1 kg of the compound is present in 100 kg of the composition.

Indicating in the present invention that a range from x to y, including the upper and lower limits of that range, is equivalent to at least x and at most y.

Indicating a range between x and y in the present invention means excluding the upper and lower limits of the range, which is equivalent to greater than x and less than y.

The liquid composition LC1 or the liquid (meth) acrylic syrup according to the present invention contains a (meth) acrylic monomer (M1) or a mixture of a (meth) acrylic monomer (M1) and (M1 + x), a (meth) acrylic polymer (P1), and a wax compound (W). The words "liquid composition LC 1" or "liquid (meth) acrylic syrup" or "liquid (meth) acrylic composition" are used synonymously throughout, said composition or syrup comprising at least three basic compounds a) (meth) acrylic polymer (P1), b) (meth) acrylic monomer (M1) and c) wax compound (W).

The dynamic viscosity of the liquid composition LC1 or of the (meth) acrylic syrup is in the range from 10 to 10000 mPa · s, preferably from 20 to 7000 mPa · s and advantageously from 20 to 5000 mPa · s, and more advantageously from 20 to 2000 mPa · s, and even more advantageously between 20 and 1000 mPa · s, and even still more advantageously between 25 and 1000 mPa · s, and most advantageously between 30 and 1000 mPa · s. The viscosity of the slurry can be easily measured with a rheometer or viscometer. The dynamic viscosity is measured at 25 ℃. If the liquid (meth) acrylic syrup has Newtonian behavior, indicating no shear thinning, the dynamic viscosity is independent of the shear in the rheometer or the speed of movement in the viscometer. If the liquid composition has a non-Newtonian behaviour, indicating shear thinning, it is heated at 25 ℃ for 1 s^-1The shear rate of (c) measures the dynamic viscosity.

The liquid composition LC1 or (meth) acrylic syrup for impregnating a fibrous substrate according to the present invention comprises, inter alia, a (meth) acrylic monomer (M1) or a mixture of (meth) acrylic monomers, (meth) acrylic polymer (P1) and a wax compound (W).

The amount of wax compound (W) in liquid composition LC1 was at least 0.1 phr, relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1). Preferably, the amount of wax compound (W) in the composition is at least 0.15 phr, more preferably at least 0.2 phr, even more preferably at least 0.25 phr, and advantageously at least 0.3 phr, and more advantageously at least 0.4 phr, and still more advantageously at least 0.5 phr, and even still more advantageously at least 0.55 phr, and most advantageously at least 0.59 phr, relative to the sum of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1).

The amount of the wax compound (W) in the composition is at most 2 phr relative to the sum of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1). Preferably, the amount of wax compound (W) in the composition is at most 1.8 phr, more preferably at most 1.5 phr, even more preferably at most 1.3 phr and advantageously at most 1.2 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

Preferably, the amount of wax compound (W) in the liquid composition LC1 is between 0.1 phr and 2 phr, relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

More preferred amounts of wax compound (W) in the liquid composition LC1, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1), are between 0.15 phr and 1.9 phr, even more preferably between 0.2 phr and 1.8 phr, still more preferably between 0.25 phr and 1.7 phr, advantageously between 0.3 phr and 1.6 phr, more advantageously between 0.4 phr and 1.5 phr, even more advantageously between 0.45 phr and 1.4 phr, and still more advantageously between 0.5 phr and 1.3 phr, and even still more advantageously between 0.55 phr and 1.3 phr, most advantageously between 0.59 phr and 1.3 phr.

As to the liquid composition LC1 of the present invention, it contained (meth) acrylic monomer (M1), (meth) acrylic polymer (P1), and wax compound (W). Upon polymerization, the (meth) acrylic monomer (M1) is converted into a (meth) acrylic polymer (P2) containing a monomer unit of the (meth) acrylic monomer (M1). In one variation, the (meth) acrylic monomer mixture is converted upon polymerization to a (meth) acrylic copolymer comprising monomer units of each (meth) acrylic monomer.

With respect to the (meth) acrylic monomer (M1), the monomer is selected from acrylic acid, methacrylic acid, alkyl acrylate monomers, alkyl methacrylate monomers, hydroxyalkyl acrylate monomers and hydroxyalkyl methacrylate monomers, and mixtures thereof.

Preferably, the (meth) acrylic monomer (Ml) is selected from acrylic acid, methacrylic acid, hydroxyalkyl acrylate monomers, hydroxyalkyl methacrylate monomers, alkyl acrylate monomers, alkyl methacrylate monomers and mixtures thereof, the alkyl group containing from 1 to 22 linear, branched or cyclic carbons; the alkyl group preferably contains from 1 to 12 straight, branched or cyclic carbons.

Advantageously, the (meth) acrylic monomer (Ml) is chosen from methyl methacrylate, 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, isobornyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate and mixtures thereof.

According to a preferred embodiment, at least 50% by weight and preferably at least 60% by weight of the (meth) acrylic monomer (M1) is methyl methacrylate.

According to a first more preferred embodiment, at least 50% by weight and 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 (M1) is a mixture of methyl methacrylate and optionally at least one other monomer.

According to a second more preferred embodiment, the liquid composition or (meth) acrylic syrup comprises between 0.01 and 10 phr by weight of monomer (M2), with respect to the sum of (meth) acrylic monomer (Ml) and (meth) acrylic polymer (P1), said (meth) acrylic monomer (M2) comprising at least two (meth) acrylic functions and advantageously between 0.1 and 5 phr by weight of said (meth) acrylic monomer (M2).

The (meth) acrylic monomer (M2) may be selected from ethylene glycol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, 1, 4-butanediol diacrylate, 1, 3-butanediol dimethacrylate or mixtures thereof.

As the (meth) acrylic polymer (P1), mention may be made of polyalkyl methacrylate or polyalkyl acrylate. According to a preferred embodiment, the (meth) acrylic polymer is polymethyl methacrylate (PMMA).

The term "PMMA" denotes a homopolymer or copolymer of Methyl Methacrylate (MMA) or a mixture thereof.

According to one embodiment, the Methyl Methacrylate (MMA) homopolymer or copolymer comprises at least 70 wt.%, preferably at least 80 wt.%, advantageously at least 90 wt.% and more advantageously at least 95 wt.% of methyl methacrylate.

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 at least two copolymers of MMA having different average molecular weights, or a mixture of at least two copolymers of MMA having different monomer compositions.

Copolymers of Methyl Methacrylate (MMA) comprise from 70 to 99.9 wt% methyl methacrylate and from 0.1 to 30 wt% of at least one monomer containing at least one ethylenic unsaturation that is copolymerizable with the methyl methacrylate.

These monomers are well known and mention may be made in particular of acrylic and methacrylic acid and alkyl (meth) acrylates in which the alkyl group contains from 1 to 12 carbon atoms. Mention may be made, as examples, of methyl acrylate and ethyl (meth) acrylate, butyl (meth) acrylate or 2-ethylhexyl (meth) acrylate. Preferably, the comonomer is an alkyl acrylate, wherein the alkyl group contains from 1 to 4 carbon atoms.

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

The weight average molecular mass of the (meth) acrylic polymer (P1) should be high, which means more than 50000 g/mol and preferably more than 100000 g/mol.

The weight average molecular mass can be measured by Size Exclusion Chromatography (SEC).

The (meth) acrylic polymer may be completely soluble in the (meth) acrylic monomer or in the (meth) acrylic monomer mixture. Which causes an increase in the viscosity of the (meth) acrylic monomer or the mixture of (meth) acrylic monomers. The resulting solution is commonly referred to as a "slurry" or "prepolymer". The liquid (meth) acrylic syrup has a dynamic viscosity value of between 10 mpa.s and 10000 mpa.s. The viscosity of the slurry can be easily measured with a rheometer or viscometer. The dynamic viscosity is measured at 25 ℃.

Advantageously, the liquid (meth) acrylic syrup does not contain additional solvent added voluntarily.

As regards the liquid composition LC1 according to the invention, it comprises a wax compound (W) which is a low-melting wax.

The wax compound (W) may be pure or a mixture of wax compounds, as long as the mixture has a melting point as given below.

The melting point of the wax compound (Wl) is indicated as freezing point. Melting points were evaluated or measured as freezing points according to ASTM D938. Preferably, the freezing point of the wax compound (W) is below 85 ℃. More preferably, the melting point of the wax compound (W1) is below 80 ℃, even more preferably below 75 ℃, even more preferably below 70 ℃, advantageously below 65 ℃ and more advantageously below 60 ℃.

More preferably, the wax compound (W) has a freezing point higher than 15 ℃. Even more preferably, the wax compound (W) has a freezing point higher than 20 ℃, even more preferably higher than 21 ℃, even more preferably higher than 22 ℃, advantageously higher than 24 ℃ and more advantageously higher than 25 ℃.

More preferably, the freezing point of the wax compound (W) is between 15 ℃ and 85 ℃. Even more preferably, the freezing point of the wax is between 20 ℃ and 80 ℃, even more preferably between 21 ℃ and 75 ℃, even more preferably between 22 ℃ and 70 ℃, advantageously between 24 ℃ and 65 ℃ and more advantageously between 25 ℃ and 60 ℃.

The density of the wax compound (W) is smaller than the density of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1) together. The density of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1) together means a composition composed of the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1). One of the components alone may have a density lower than that of the wax compound (W), but the density of the composition of the two components together is higher than that of the wax compound (W).

More preferably, the density of the wax compound (W) is less than 1.1 g/cm³. More preferably, the density of the wax compound (W) is less than 1.05 g/cm³And still more preferably less than 1.02 g/cm³Even more preferably still less than 1.0 g/cm³Advantageously less than 0.99 g/cm³And more advantageously less than 0.98 g/cm³。

More preferably, the density of the wax compound (W) is higher than 0.7 g/cm³. Even more preferably, the density of the wax compound (W) is higher than 0.72 g/cm³Even more preferably still higher than 0.75 g/cm³Even more preferably still highAt 0.78 g/cm³Advantageously higher than 0.8 g/cm³And more advantageously higher than 0.85 g/cm³。

More preferably, the wax compound (W) has a density of 0.7 g/cm³And 1.1 g/cm³In the meantime. Even more preferably, the wax compound (W) has a density of 0.72 g/cm³And 1.05 g/cm³Between, even more preferably still 0.75 g/cm³And 1.02 g/cm³Between, even more preferably still 0.78 g/cm³And 1.0 g/cm³Between, advantageously 0.8 g/cm³And 0.99 g/cm³And more advantageously between 0.85 g/cm³And 0.98 g/cm³In the meantime.

As for the wax compound (W), it may be made of natural wax or synthetic wax or a mixture of both blended.

The wax compounds (Wl) may be made of natural wax or synthetic wax or a mixture of both blended, as long as they have the desired freezing point and density as defined above.

Useful natural waxes include vegetable waxes, animal waxes and mixtures thereof, and may also be mineral waxes such as petroleum or montan wax (lignite wax), peat or montan wax (montan wax).

Useful synthetic waxes include partially synthetic waxes, such as fatty acid amides and mixtures thereof, and may also be fully synthetic waxes, such as polyolefin waxes or fischer-tropsch waxes, or polar synthetic waxes.

Since the wax compound (W) may be a mixture, the melting point is not a single peak or point but may be a range. However, the melting range is below, above, or within a specified temperature.

Optionally, the liquid composition additionally comprises d) an initiator (Ini).

The amount of initiator (Ini) in the composition is at least 0.1 phr relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1). Preferably, the amount of initiator (Ini) in the composition is at least 0.2 phr, more preferably at least 0.5 phr, even more preferably at least 0.75 phr and advantageously at least 1 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

The amount of initiator (Ini) in the composition is at most 15 phr relative to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1). Preferably, the amount of initiator (Ini) in the composition is at most 12 phr, more preferably at most 10 phr, even more preferably at most 8 phr and advantageously at most 5 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

The amount of initiator (Ini) in the composition is between 0.1 phr and 15 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1). Preferably, the amount of initiator (Ini) in the composition is between 0.2 phr and 12 phr, more preferably between 0.5 phr and 10 phr, even more preferably between 0.75 phr and 8 phr and advantageously at most between 1 phr and 5 phr, with respect to the sum of (meth) acrylic monomer (M1) and (meth) acrylic polymer (P1).

With respect to the initiator (Ini), the initiator generates a free radical which initiates free radical polymerization of one or more monomers to initiate formation of a polymer chain by propagation.

Preferably, the initiator (Ini) is activated by heat.

The thermally activated initiator (Ini) is preferably a free radical initiator.

The radical initiator (Ini) may be selected from compounds comprising peroxy groups or compounds comprising azo groups, and is preferably selected from compounds comprising peroxy groups or mixtures thereof.

Preferably, the peroxy group-containing compound contains from 2 to 30 carbon atoms.

Preferably, the compound comprising a peroxy group is selected from diacyl peroxides, peroxyesters, peroxydicarbonates, dialkyl peroxides, peroxy acetals, hydroperoxides or peroxy ketals (peroxyketals).

More preferably, the initiator (Ini) is selected from diisobutyryl peroxide, cumyl peroxyneodecanoate, di (3-methoxybutyl) peroxydicarbonate, 1,3, 3-tetramethylbutyl peroxyneodecanoate, cumyl peroxyneoheptanoate, di-n-propyl peroxydicarbonate, tert-amyl peroxyneodecanoate, di-sec-butyl peroxydicarbonate, diisopropyl peroxydicarbonate, di (4-tert-butylcyclohexyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, tert-amyl peroxyneodecanoate, tert-butyl peroxyneodecanoate, di-n-butyl peroxydicarbonate, dihexadecyl peroxydicarbonate, dimyristyl peroxydicarbonate, 1,3, 3-tetramethylbutyl peroxypivalate, tert-butyl peroxyneoheptanoate, Tert-amyl peroxypivalate, tert-butyl peroxypivalate, bis- (3,5, 5-trimethylhexanoyl) peroxide, dilauroyl peroxide, didecanoyl peroxide, 2, 5-dimethyl-2, 5-bis (2-ethylhexanoylperoxide) -hexane, 1,3, 3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydiethylacetate, tert-butyl peroxyisobutyrate, 1-bis (tert-butylperoxy) -3,3, 5-trimethylcyclohexane, 1-bis (tert-amylperoxy) -cyclohexane, 1-bis (tert-butylperoxy) -cyclohexane, di (tert-butylperoxy) -cyclohexane, lauroyl peroxide, dilauroyl peroxide, didecanoyl peroxide, di (2-ethylhexanoyl peroxide), di (2-ethylhexoate-2, 5-ethylhexoate), di (tert-butylperoxy) -hexane, di (tert-butyl peroxy-2, 2-butyl-ethyl-2, 5-ethylhexoate), di (tert-butyl peroxy-butyl-ethyl-hexanoate), di (tert-butyl-peroxy-3, 3,3, 5-trimethylcyclohexane, di-tert-butyl-tert-butyl-peroxy-ethyl-peroxy-ethyl-2, di (di-tert-butyl-2-peroxy-butyl-ethyl-butyl-ethyl-peroxy-butyl-peroxy-cyclohexane, 1-di-tert-di-tert-butyl-tert-butyl-, T-amyl peroxy-2-ethylhexyl carbonate, t-amyl peroxyacetate, t-butyl peroxy-3, 5, 5-trimethylhexanoate, 2-di (t-butylperoxy) -butane, t-butyl peroxyisopropylcarbonate, t-butyl peroxy-2-ethylhexyl carbonate, t-amyl peroxybenzoate, t-butyl peroxyacetate, butyl 4, 4-di (t-butylperoxy) valerate, t-butyl peroxybenzoate, di-t-amyl peroxide, dicumyl peroxide, di (2-t-butyl-peroxyisopropyl) -benzene, 2, 5-dimethyl-2, 5-di (t-butylperoxy) -hexane, t-butylcumyl peroxide, 2, 5-dimethyl-2, 5-di (t-butylperoxy) hex-3-yne, di-tert-butyl peroxide, 3,6, 9-triethyl-3, 6, 9-trimethyl-1, 4, 7-triperoxonane (triperoxonane), 2 '-Azobisisobutyronitrile (AIBN), 2' -azobis- (2-methylbutyronitrile), azobisisobutyramide, 2 '-azobis (2, 4-dimethylvaleronitrile), 1' -azobis (hexahydrobenzonitrile) or 4,4'-azobis (4-cyanovaleric acid) (4, 4' -azobis (4-cyanovaleric)) and mixtures thereof.

In order to maintain the dynamic viscosity of the liquid composition LC1 or the (meth) acrylic syrup (which also allows good impregnation of the fibrous substrate if necessary), and to maintain the thermoplastic properties of the matrix obtained after polymerization of the fibrous substrate pre-impregnated with the syrup, the compounds of the syrup are incorporated in the following percentages by mass:

the (meth) acrylic monomer (Ml) or the (meth) acrylic monomer (Ml) in the liquid composition LCl or the (meth) acrylic syrup is present in a proportion of between 40% by weight and 90% by weight, and preferably between 45% by weight and 85% by weight, and more preferably between 50% by weight and 85% by weight, and still more preferably between 60% by weight and 85% by weight, and advantageously between 65% by weight and 85% by weight of the composition comprising the (meth) acrylic monomer (M1) or the (meth) acrylic monomer (M1) and the (meth) acrylic polymer (P1).

The (meth) acrylic polymer (P1) or the (meth) acrylic polymer(s) (P1) in the liquid composition LC1 or the (meth) acrylic syrup is present in a proportion of at least 1% by weight, preferably at least 5% by weight and advantageously at least 10% by weight of the composition comprising the (meth) acrylic monomer(s) (M1) and the (meth) acrylic polymer(s) (P1).

The (meth) acrylic polymer (P1) or the (meth) acrylic polymer(s) (P1) in the liquid composition LC1 or the liquid (meth) acrylic syrup is present in a proportion of not more than 50% by weight, preferably not more than 40% by weight, still more preferably not more than 35% by weight and advantageously not more than 30% by weight of the composition comprising the (meth) acrylic monomer (M1) or the (meth) acrylic monomer(s) (M1) and the (meth) acrylic polymer (P1).

Preferably, the (meth) acrylic polymer (P1) or the one or more (meth) acrylic polymers (P1) in the liquid composition LC1 or the liquid (meth) acrylic syrup are present in a proportion of between 10% and 60% by weight, and preferably between 15% and 55% by weight, and more preferably between 15% and 50% by weight, and still more preferably between 15% and 40% by weight and advantageously between 15% and 35% by weight of the composition comprising the (meth) acrylic monomer (M1) or the one or more (meth) acrylic monomers (M1) and the (meth) acrylic polymer (P1).

The composition comprising the (meth) acrylic monomer (M1) or one or more (meth) acrylic monomers (M1) and the (meth) acrylic polymer (P1) is also a liquid mixture prepared in each method of the present invention. In a composition comprising a (meth) acrylic monomer (M1) or one or more (meth) acrylic monomers (M1) and a (meth) acrylic polymer (P1), the two compounds add up to 100% by weight; this may be considered as 100 parts by weight, and the amounts of the wax compound (W) and other additives are calculated on this basis.

All optional additives and fillers are added to the liquid (meth) acrylic syrup prior to impregnation and or polymerization.

As for the method of producing the liquid composition LC1 or the (meth) acrylic syrup, the first step consists in preparing a first syrup comprising the (meth) acrylic monomer (Ml) or the (meth) acrylic monomer mixture and the (meth) acrylic polymer (P1).

The wax compound (W) is added to the composition prepared in the first step.

If desired, initiator (Ini) is then added to the slurry in the above proportions to maintain a dynamic viscosity of between 10 and 10000 mPa s at 25 ℃.

Preferably, the initiator (Ini) is at a temperature T lower than 50 ℃, more preferably lower than 40 ℃, advantageously lower than 30 ℃ and more advantageously lower than 25 ℃_addThe following is added.

The liquid composition according to the invention, as detailed in the preceding paragraph, can be used for impregnating fibers or fibrous substrates or for manufacturing thermoplastic parts or for manufacturing composite parts.

With respect to the method of impregnating a fiber or a fibrous substrate, it includes the step of impregnating a fibrous substrate with the liquid composition LCl or a (meth) acrylic syrup.

The impregnation step may be carried out in a mould or a tank.

If the viscosity of the liquid (meth) acrylic slurry at a given temperature is slightly too high for the impregnation process, the slurry can be heated to have a more fluid slurry for adequate wetting and proper and complete impregnation of the fibrous substrate.

As fibrous substrates there may be mentioned a plurality of fibers, unidirectional rovings or continuous filament mats, fabrics, felts or nonwovens, which may be in the form of strips, loops, braids, locks or sheets. The fibrous material can have various forms and dimensions, one, two, or three dimensions. The fibrous substrate comprises an assembly of one or more fibers. When the fibers are continuous, their assembly forms a fabric.

The one-dimensional form corresponds to linear long fibers. The fibers may be discontinuous or continuous. The fibers may be randomly arranged or arranged parallel to each other in the form of continuous filaments. Fibers are defined by their aspect ratio, which is the ratio between the length and diameter of the fiber. The fibers used in the present invention are long fibers or continuous fibers. The aspect ratio of the fibres is at least 1000, preferably at least 1500, more preferably at least 2000, advantageously at least 3000 and more advantageously at least 5000, even more advantageously at least 6000, still more advantageously at least 7500 and most advantageously at least 10000.

The two-dimensional form corresponds to a non-woven or woven fibre mat or reinforcement or fibre bundle, which may also be braided. Even if the two-dimensional form has a certain thickness and thus in principle a third dimension, it is considered to be two-dimensional according to the invention.

For example, the three-dimensional form corresponds to a non-woven fiber mat or reinforcement or a stack or folded fiber bundle or a mixture thereof, the assembly of the two-dimensional form in the third dimension.

The source of the fibrous material may be natural or synthetic. As natural materials, mention may be made of vegetable fibers, wood fibers, animal fibers or mineral fibers.

Natural fibers are, for example, sisal, jute, hemp, flax, cotton, coconut fibers and banana fibers. Animal fibres are for example wool or hair.

As synthetic material, mention may be made of polymer fibers selected from thermosetting polymer fibers, thermoplastic polymer fibers or mixtures thereof.

The polymer fibers may be composed of polyamides (aliphatic or aromatic), polyesters, polyvinyl alcohol, polyolefins, polyurethanes, polyvinyl chloride, polyethylene, unsaturated polyesters, epoxies, and vinyl esters.

The mineral fibres may also be selected from glass fibres, in particular of the E, R or S2 type, carbon fibres, boron fibres or silica fibres.

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

Preferably, the fibrous substrate is selected from mineral fibers.

The diameter of the fibres of the fibrous base material is between 0.005 μm and 100 μm, preferably between 1 μm and 50 μm, more preferably between 5 μm and 30 μm and advantageously between 10 μm and 25 μm.

Preferably, the fibers of the fibrous substrate of the present invention are selected from continuous fibers for the one-dimensional form (meaning that the aspect ratio is not necessarily applied for long fibers), or long fibers or continuous fibers for the two-dimensional or three-dimensional form of the fibrous substrate.

According to another additional aspect, the present invention relates to a polymer composite comprising a thermoplastic (meth) acrylic matrix and a fibrous substrate used as reinforcement, wherein the fibrous substrate consists of long fibers, said composite being characterized in that the thermoplastic (meth) acrylic matrix is obtained after polymerization of the fibrous substrate pre-impregnated with the liquid composition LC1 or (meth) acrylic syrup according to the present invention.

Another aspect of the invention is a method for manufacturing a mechanical or structural part or product, comprising the steps of:

i) the fibrous substrate is impregnated with a liquid composition LC1 or a (meth) acrylic slurry according to the invention,

ii) polymerizing the liquid composition LC1 or the (meth) acrylic syrup impregnating the fibrous base material.

In all embodiments or aspects of the invention, the polymerization of the liquid composition LC1 or the (meth) acrylic syrup, which has been impregnated with the fibrous substrate during the polymerization step in the process of manufacturing a mechanical or structural part or product, occurs at a temperature between 40 ℃ and 140 ℃.

According to another additional aspect, the present invention relates to the use of liquid composition LCl for the manufacture of thermoplastic parts or for the manufacture of composite parts.

According to another additional aspect, the present invention relates to the use of the liquid composition LCl prepared by the method of the present invention for the manufacture of thermoplastic parts or for the manufacture of composite parts.

According to another additional aspect, the invention relates to a method of manufacturing a thermoplastic part by a method comprising the steps of:

i) preparation of a liquid mixture of (meth) acrylic Polymer (P1) and (meth) acrylic monomer (M1)

ii) adding the wax compound (W) to the mixture prepared in the previous step.

iii) placing the liquid (meth) acrylic composition or liquid composition LC1 prepared in i) and ii) in a tool for polymerization, said composition being characterized in that it additionally comprises:

d) an initiator (Ini);

the liquid (meth) acrylic syrup or liquid composition LC1 according to any one of claims 1 to 10 having a dynamic viscosity at 25 ℃ of between 10 and 10000 mPas,

iv) polymerization.

According to another additional aspect, the invention relates to a method of manufacturing a composite part by a method comprising the steps of:

i) preparation of a mixture of (meth) acrylic Polymer (P1), (meth) acrylic monomer (M1) and wax Compound (W)

ii) adding the initiator (Ini) to the mixture prepared in the previous step.

iii) impregnating the fibre or fibrous substrate with the liquid composition or liquid composition LC1 prepared in i) and ii), said composition being characterized in that it comprises:

a) a (meth) acrylic polymer (P1),

b) a (meth) acrylic monomer (M1),

c) a wax compound (W) and

d) two initiators (Ini 1) and (Ini 2);

said liquid (meth) acrylic syrup or liquid composition LC1 having a dynamic viscosity at 25 ℃ of between 10 and 10000 mPas,

iv) polymerization.

According to a sixth aspect, with regard to the method of manufacturing a thermoplastic composite part, the method preferably comprises the step of adding an initiator (Ini) to the liquid composition LC1 before placing said liquid composition LC1 into the tool for polymerization.

With respect to the methods of making thermoplastic composite parts or composite parts, as well as parts or products of machinery or construction, various methods can be used to prepare these parts. Open molding (open molding), pultrusion, hand lay-up (hand lay-up) and filament winding may be mentioned.

A first preferred manufacturing method for manufacturing composite parts is a method according to which the liquid composition LC1 is transferred to the fibrous substrate by impregnating the fibrous substrate in an open mould.

A second preferred manufacturing process for manufacturing composite parts is the process according to which a liquid composition is used in the pultrusion process. The fibers are guided through a resin batch comprising the composition according to the invention. The fibers as the fibrous base material are for example in the form of unidirectional rovings or continuous filament mats. After impregnation in the resin tank, the wetted fibers are drawn through a heated die where polymerization occurs.

The third preferred method of manufacture is hand lay-up molding.

A fourth preferred manufacturing method is filament winding.

The method for manufacturing composite parts and parts or products of machines or structures may additionally comprise a post-forming step. Post-forming includes bending to change the form of the composite part. Preferably, the post-forming is carried out after the polymerization step.

The method for manufacturing composite parts as well as mechanical or structural parts or products may additionally comprise a step of welding or gluing or laminating. Preferably, the welding or gluing or laminating is performed after the polymerization step.

The thermoplastic composite parts obtained from the process according to the invention can be post-shaped after polymerization of the liquid composition LC1 according to the invention. Shaping includes bending to change the form of the composite material.

The thermoplastic parts or the manufactured composite parts obtained after polymerization of the liquid composition of the invention and/or obtained by the method according to the invention may be welded, glued or laminated.

According to another additional aspect, the present invention relates to a polymer composite comprising a thermoplastic (meth) acrylic matrix and a fibrous substrate used as reinforcement, wherein the fibrous substrate consists of long fibers, the composite being characterized by a thermoplastic (meth) acrylic matrix obtained after polymerization of the liquid composition LC1, the fibrous substrate having been pre-impregnated with the liquid composition LC 1.

According to yet another additional aspect, the invention relates to a mechanical part or structural element made of said polymer composite.

According to yet another additional aspect, the invention relates to a mechanical part or structural element made by any of the manufacturing methods of the invention.

As to the use of mechanical parts made of the composite material thus manufactured, mention may be made of automotive applications, transport applications such as buses or trucks, marine applications, railway applications, sports, aerospace and aeronautical (aeronautical and aeronautical) applications, photovoltaic applications, computer-related applications, construction and building applications, telecommunication applications and wind energy applications.

Mechanical parts made of composite materials are, in particular, motor vehicle parts, ship parts, bus parts, train parts, sporting goods, aircraft or helicopter parts, spacecraft or rocket parts, optoelectronic component parts, materials for construction or construction, such as composite material rebars, dowels and stirrups for civil engineering and high-rise buildings, wind turbine parts, such as caps for the girders of wind turbine blades, furniture parts, construction or building parts, telephone or cell phone parts, computer or television parts, or printer or copier parts.

[ method ]

Density of Compounds (having units of g/cm)³) It is simply calculated by measuring the mass and volume of the compound and then dividing the mass by the volume. Preferably, the density is measured with a pycnometer, and even more preferably at 25 ℃.

Freezing point was measured according to ASTM D938.

[ examples of embodiments]

A liquid composition was prepared by dissolving 25 wt.% of PMMA (BS 520, MMA copolymer comprising ethyl acrylate as comonomer) as (P1) in 75 wt.% of methyl methacrylate as (Ml), which is stable with HQME (hydroquinone monomethyl ether). As wax compound (W) Feruwax 13015 from the company PARAMELT BV was used. The congealing point of the wax was 52 ℃ to 54 ℃ according to ASTM D938. The wax compounds were dispersed in the liquid compositions in different proportions from 0.3 phr to 1 phr to prepare several liquid compositions LC1 according to the invention as shown in table 1. The dynamic viscosity of the composition at 25 ℃ was 500 mPa · s.

TABLE 1 compositions

	Wax Compound (W) in liquid composition LC1 [ phr]
		Comparative example 1= CoEX1	0
Example 1= EX1	0.3
		Example 2 = EX2	0.5
Example 3 = EX3	0.7
		Example 4 = EX4	1.0

Each composition was applied in a known amount to a previously weighed fabric and exposed to air at 23 ℃. The weight of both was measured together every two minutes.

The weight loss of Methyl Methacrylate (MMA) was followed gravimetrically at 23 ℃.

TABLE 2 evaluation of MMA evaporation

。

Table 2 shows that the evaporated MMA is decreasing over time for the examples where the wax compound is present. The evaporation was greatly reduced when 0.3 phr of wax compound was used, very low when 0.5 phr or more of wax compound was used, and little evaporation was observed when 0.7 phr and 1 phr of wax compound were used.