TWO-STEPS LIGHT AND HEAT CURABLE RESIN COMPOSITION

Abstract

The present invention relates to the field of a protection system based on composite material used in ballistics. The application relates to a two-steps light and heat curable resin composition, a process of forming in a first step a prepreg using said resin and in a second step a protection system comprising the laminated composite of the invention.

Claims

1. A two-steps light and heat curable resin composition comprising: from 0.01 to 11% of a photoinitiating system, from 5 to 50% of a polymerisable resin, and from 40% to 85% of a thermoplastic resin, the percentage being weight % with regards to the total mass of the composition.

2. The composition of claim 1, wherein the polymerisable resin is an ethylenically unsaturated monomer, the polymerization of which may be effected by free radical polymerization.

3. The composition of claim 1, wherein the polymerisable resin is an cyclic ether-containing monomer, the polymerization of which may be effected by cationic polymerization.

4. The composition of claim 1, wherein the polymerisable resin is an ethylenically unsaturated monomer, the polymerization of which may be effected by free radical polymerizations, or an cyclic ether-containing monomer, the polymerization of which may be effected by cationic polymerization.

5. The composition of claim 1, further comprising one or more additive(s).

6. The composition of claim 1, wherein the photoinitiating system is a cationic photoinitiating system and/or a radical photoinitiating system.

7. The composition of claim 1, wherein the photoinitiating system comprises isopropylthioxanthone, 1-Chloro-4-propoxythioxanthone, 2,4-diethylthioxanthone, an anthracene, or mixtures thereof.

8. The composition of claim 1, wherein the thermoplastic resin is ethylenevinyl acetate, polyvinyl alcohol, polyvinyl butyral or mixtures thereof.

9. The composition of claim 5, wherein the organic solvent comprises ketones, 1-methoxy-2-propanol or (2-methoxy-méthylethoxy)-propanol).

10. A process for preparing a prepreg and a laminated composite comprising the steps of: 1) coating a first support with the composition according to claim 1; 2) partially photocuring the composition on the first support, by subjecting said composition to a light emission source until a 20 to 90% conversion rate of the reactive functions of the polymerisable resin is reached; 3) optionally transferring the composition obtained in step 2) from the first support onto a second support; and obtaining the prepreg.

11. The process of claim 10, further comprising a step 4) of preparing a laminated composite, said step 4) comprising a thermocuring of the prepreg obtained in step 2) or in step 3); and obtaining the laminated composite.

12. The process according to claim 11, further comprising a step 3a) of superimposing at least 2 prepreg layers obtained in step 2) or in step 3), before carrying out step 4) and obtaining laminated composite.

13. The process of claim 10, wherein the first support and/or the second support comprise(s) a plurality of fibers.

14. The process of claim 10, wherein the first support and the second support are identical or different.

15. The process of claim 14, wherein the first support and the second support are different and the first support comprises polyethylene terephtalate film.

16. A laminated composite obtained by the process according to claim 11.

17. A laminated composite comprising one or more prepreg layer(s), each prepreg comprising a cured composition according to claim 1, and a support comprising a plurality of fibers.

18. (canceled)

19. The composition of claim 5, wherein the one or more additive(s) is an organic solvent, a filler, a dye, mixed elastomer epoxy resin, rubber or mixtures thereof.

20. The composition of claim 1, wherein the photoinitiating system comprises onium salts, phosphine oxides, ferrocenes and thianthrenium salts or mixtures thereof.

21. The process of claim 11, wherein the thermocuring is performed at a temperature from 100 to 200° C., under a pressure from 0.5 to 5 MPa.

22. The process of claim 13, wherein the fibers comprise aromatic polyamide fibers, natural fibers, basalt fibers, carbon fibers, glass fibers, or hybrids thereof.

23. The laminated composite of claim 17, wherein the fibers comprise aromatic polyamide fibers, natural fibers, basalt fibers, carbon fibers, glass fibers, or hybrids thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0035] Applicants surprisingly found a new light (preferably visible-UV) and heat curable resin composition that solves the main issues exposed above. In particular, the composition according to the invention requires no phenolic resin. The amount of resin necessary is usually lower than in the known technologies and the composition may be used in a process of manufacture of laminated composite that fulfil the requirements of ballistics use.

[0036] On a first aspect, the invention relates to a two-steps light and heat curable resin composition comprising a photoinitiating system, a polymerisable resin and a thermoplastic resin.

[0037] Advantageously, the composition according to the invention comprises: [0038] from 0.01 to 11% of a photoinitiating system, preferably cationic photoinitiating system and/or a radical photoinitiating system, and more preferably a photoinitiating system comprising one or more compounds chosen from the group comprising iodonium, ferrocene, thianthrenium and sulfonium based compounds, phosphine oxides, hydroxyacetophenones, alkylaminoacetophenones and benzoin ethers, [0039] from 5 to 50% of a polymerisable resin, preferably chosen in the group comprising cyclic ether, epoxy, acrylate, epoxy-acrylate, methacrylate, styrene, ethylene, propylene, N-vinyl acrylamide, N-vinylpyrolidone resins, elastomer-epoxy and a mixture thereof, [0040] from 40% to 70% of a thermoplastic resin, preferably chosen in the group comprising polyvinyl butyral (PVB), polyvinyl alcohol (PVA) and ethylene-vinyl acetate (EVA).

[0041] The percentage are weight % with regards to the total mass of the composition.

[0042] In the present disclosure, it is meant by “two-steps curable” when referred to the compositions described herein, to a composition whose polymerization can be triggered by two different ways, preferably light and heat.

[0043] It is meant by “light curable” (preferably “visible-UV curable”), when refered to the compositions described herein, to a composition whose polymerization can be triggered by light emissions, preferably visible-UV.

[0044] It is meant by “heat curable”, when refered to the compositions described herein, to a composition whose polymerization can be triggered by heat exposure, preferably temperature above 100° C.

[0045] Therefore, a two-steps light and heat curable composition may be understood as a composition that is able to cure in two steps, first activated by light irradiation followed by a thermal reaction.

[0046] In the present disclosure, “initiator” or “initiating” means a chemical compound or combination of compounds that initiates a polymerization reaction.

[0047] It is therefore meant by “photoinitiating system”, a compound or a combination of compounds that, under the light radiation (preferably UV-visible), generates chemical active species (such as radicals or cations for example) which will be responsible for the initiation of the photopolymerization reaction, and therefore makes it possible to increase the efficiency of the photopolymerization reaction. The photoinitiating system may be chosen as a function of the light source used, according to its ability to effectively absorb the selected radiation. It will for example be possible to choose the suitable photoinitiating system using its UV-visible absorption spectrum. The photoinitiating system may comprise a “photoinitiator”. The photoinitiating system may also act as a “photosensitizer”, a compound that absorbs the energy radiation where the photoinitiator doesn't absorb and transfers it to the aforesaid photoiniator. The photosensitizer generally increases the efficiency of the photopolymerisation reaction or to enhance the photopolymerisation reaction when the photoiniator was not sufficient alone. Depending on the condition of radiation and type of resin a compound may act as a photoinitiator and/or as a photosensitizer.

[0048] Advantageously, the photoiniating system is suitable for working with irradiation sources that emit in the near-visible range.

[0049] Advantageously, the photoinitiating system may comprise a cationic photoinitiator and/or a radical photoinitiator.

[0050] Advantageously, the photoinitiating system may comprise one or more compounds selected from the group comprising onium salts, organometallic complexes, and non-ionic photoacids.

[0051] Advantageously, the onium salts may be selected from diaryliodonium salts and derivatives thereof, triarylsulfonium salts and derivatives thereof, and mixtures thereof. Said onium salts have preferably hexafluoroantimonate, hexafluorophosphate or tetrafluoroborate anions. Preferably the onium salts may be selected from of (4-methylphenyl)[4-(2-methylpropyl)phenyl]iodonium hexafluorophosphate, Bis-(4-methyl-phenyl)iodonium hexafluorophosphate), Bis(dodecyl phenyl) iodonium hexafluorophosphate, 9-(4-hydroxyethoxyphenyl) thianthrenium hexafluorophosphate, diphenyl iodonium triflate, and mixtures thereof.

[0052] Advantageously, the organometallic complexes may be selected from metallocenium salts, preferably from among ferrocenium salts such as cyclopentadienylcumen-iron hexafluorophosphate.

[0053] Advantageously, the non-ionic photoacids may be selected from alkyl/aryl sulfonic acid, fluorinated sulfonic acids, sulfonimides, tetra-aryl boronic acids, and mixtures thereof.

[0054] Advantageously, the photoinitiating system may comprise one or more compounds chosen in the group comprising: [0055] acetophenones, alkoxyacetophenones and derivatives, such as 2,2-dimethoxy-2-phenyleacetophenone and 2,2-diethyl-2-phenylacetophenone; [0056] hydroxyacetophenones and derivatives, such as 2,2-dimethyl-2-hydroxyacetophenone, 1-hydroxycyclohexylehenyle cetone, 2-hydroxy-4′-(2-hydroxyethoxy)-2-methyl-propriophenone and 2-hydroxy-4′-(2-hydroxypropoxy)-2-methyl-propriophenone; [0057] alkylaminoacetophenones and derivatives, such as 2-methyl-4′-(methylthio)-2-morpholino-propriophenone, 2-benzyl-2-(dimethylamino)-4-morpholino-butyrophenone and 2-(4-(methylbenzyl)-2-(dimethylamino)-4-morpholino-butyrophenone; [0058] benzoin ethers and derivatives, such as benzoin benzyl-, methyl- and isopropyl-ethers; [0059] phosphine oxides and derivatives, such as diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), ethyl-(2,4,6-trimethylbenzoyl)phenylphosphine oxide (TPO-L) and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylphenyle phosphine oxide (BAPO); [0060] benzophenones and derivatives, such as 4-phenylbenzophenone, 4-(4′methylphenylthio)benzophenone, 1-[4-[(4-benzoylphenyl)thio]phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]-1-propanone; [0061] thioxanthones and derivatives, such as isopropylthioxanthone (ITX), 1-Chloro-4-propoxythioxanthone (CPTX) 2,4-diethylthioxanthone (DETX), 2,4-dimethylthioxantone, 2-chlorothioxanthone and 1-chloro-4-isopropylthioxanthone; [0062] anthracene and derivatives, such as 9.10-diethoxy-anthracene, 9,10-Diethoxyanthracene, Alpha-Methyl-9-anthracenemethanol, 9-Hydroxymethylanthracene, Acide 9-anthracenecarboxylique, 9-Vinylanthracene, 9,10-Anthracene-dicarbonitrile, 9-Methylanthracene, 2-Ethyl-9,10-dimethoxyanthracene, 1,2,3,4-Dibenzanthracene, 9,10-Dicyanoanthracene, 9-Cyanoanthracene; [0063] quinones and derivatives, such as antraquinones including 2-ethylantraquinone and camphroquinones; [0064] benzoyl formate esters and derivatives, such as methylbenzoylformate; [0065] metallocenes and derivatives, such as ferrocene, titanium bis(eta 5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro)-3-(1H-pyrrol-1-yl)-phenyl) and iron (cumene)cyclopentadienyl hexafluorophosphate; [0066] dibenzylidene ketones and derivatives, such as p-dimethylaminoketone; [0067] coumarines and derivatives, such as 5-methoxy coumarine, 7-methoxy coumarine, 7-diethylamino coumarine and N-phenyleglycin coumarine; and [0068] dyes such as triazines and derivatives, fluorones and derivatives, cyanines and derivatives, safranines and derivatives, 4,5,6,7-tetrachloro-3′,6′-dihydroxy-2′,4′,5′,7′-tetraiodo-3H-spiro[isobenzofuran-1,9′-xanthen]-3-one, pyrylium or thiopyrylium and derivatives, thiazines and derivatives, flavines and derivatives, pyronines and derivatives, oxazines and derivatives, rhodamines and derivatives.

[0069] Preferably the photoinitating system may comprise a compound selected among onium salts (such as iodonium and sulfonium), phosphine oxides (such as TPO, BAPO), a ferrocene or a thianthrenium salt.

[0070] Advantageously, the photoinitiating system may further comprise isopropylthioxanthone (ITX), 1-Chloro-4-propoxythioxanthone (CPTX), 2,4-diethylthioxanthone (DETX), an anthracene or mixtures thereof.

[0071] It is meant by “polymerisable resin”, a resin which may consist only of monomers, prepolymers or a mixture of monomers and prepolymers.

[0072] Advantageously, the polymerisable resin may be selected from the group comprising: [0073] (i) an ethylenically unsaturated monomer and/or prepolymer, the polymerization of which may be effected by free radical polymerization, preferably acrylate monomer and/or prepolymer; and/or [0074] (ii) an cyclic ether-containing monomer and/or prepolymer; the polymerization of which may be effected by cationic polymerization, preferably epoxy-containing monomer and/or prepolymer.

[0075] Advantageously, the polymerizable resin may be an ethylenically unsaturated monomer and/or prepolymer, the polymerization of which may be effected by free radical polymerization. As used herein, the term “ethylenically unsaturated monomer” refers to a monomer that contains at least one carbon-carbon double bond. Preferably, ethylenically unsaturated monomers whose polymerization may be effected by free radical polymerization, contains at least one carbon-carbon double bond that is conjugated with an aryl moiety (e.g., phenyl), a carboxyl (C═O) group, or another double bond. Such monomers in this category include for example acrylates —[(ROCO)CHCH2]- (acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, etc . . . ), methacrylates —[(ROCO)C(Me)CH2]- (methacrylic acid, methyl methacrylic acid, etc . . . ), styrene, ethylene, propylene, N-vinyl acrylamide, N-vinylpyrolidone.

[0076] Advantageously, the polymerizable resin may be an cyclic ether-containing monomer and/or prepolymer whose polymerization may be effected by cationic polymerization. Examples of these monomers include vinyl ethers —[ROCHCH2]- such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; oxetane and and epoxy monomers. As used herein, the term “epoxy monomer” refers to a moiety comprising an oxirane moiety having the structure:

##STR00001##

wherein “*” denotes the point of attachment of the oxirane moiety to the rest of the monomer. For example, the polymerizable component may be the epoxide monomer (EPOX) having the following structure:

##STR00002##

[0077] Advantageously, the polymerizable component may be a mixture of two or more components which are polymerizable via different polymerization mechanisms: free radical polymerization or cationic polymerization, respectively. For example, the polymerizable component may be a mixture of TMPTA and EPOX. Other examples include mixtures vinylether/acrylate and vinylether/epoxy.

[0078] Preferably, the polymerisable resin may be chosen from the group comprising cyclic ether, epoxy, acrylate, epoxy-acrylate and mixtures thereof. For example, the polymerisable resin may be chosen from the group comprising DER 331 (CAS NO. 25085-99-8), DGEBA (CAS NO. 1675-54-3), SR238 (6-prop-2-enoyloxyhexyl prop-2-enoate, CAS NO. 88250-32-2), SR508 (dipropylene glycol diacrylate, CAS NO. 57472-68-1) and mixtures thereof.

[0079] Advantageously, the composition according to the invention does not comprise any phenol or phenolic derivatives such as phenolic resin, phenoplast (formaldehyde-phenol resin) or cresol resins.

[0080] It is meant by “thermoplastic resin”, a resin that repeatedly softens when heated above a certain temperature. This thermokinetic behavior will therefore result in the presence of a melting peak. On the other hand, the thermoplastic resin will become hard again below this temperature.

[0081] Advantageously, the thermoplastic resin is chosen from the group comprising polyvinyl butyral (PVB), polyvinyl alcohol (PVA), ethylene-vinyl acetate (EVA) and mixtures thereof.

[0082] Usually, acetals are formed by the well-known reaction between aldehydes and alcohols. The polyninyl butyral refers to any products of acetalation of polyvinyl alcohol with one or more aliphatic aldehydes. The ethylene-vinyl acetate consists of copolymer of ethylene and vinyl acetate.

[0083] Advantageously, the thermoplastic resin may be chosen from the group comprising polyvinyl butyral having an average molecular weight of from 10000 g/mol to 110000 g/mol, preferably from 50000 g/mol to 100000 g/mol. Polyvinyl butyral may be of formula I:

##STR00003##

wherein the arrangement of the acetal, acetyl and hydroxyl groups are not to be regarded as fixed, n, p and r are integers and the polyvinyl butyral has an average molecular weight of from 10000 g/mol to 110000 g/mol, preferably from 50000 g/mol to 100000 g/mol.

[0084] Advantageously, the thermoplastic resin may be chosen from the group comprising polyvinyl alcohol having an average molecular weight of from 9000 g/mol to 190000 g/mol. Polyvinyl alcohol may be of formula II:

##STR00004##

wherein n is an integer and the polyvinyl alcohol has an average molecular weight of from 9000 g/mol to 190000 g/mol. Preferably, the polyvinyl alcohol is chosen from the groupe comprising the following ultra low, low, medium, high viscosity Selvol™ PVA, and mixtures thereof:

TABLE-US-00002 TABLE 2 Selvol ™ PVA. Viscosity Degree of Weight Average Molecular Viscosity Type Polymerization Weight Range 3-4 cps Ultra Low 150-300 13,000-23,000 5-6 cps Low 350-650 31,000-50,000 22-30 cps Medium 1000-1500  85,000-124,000 45-72 cps High 1600-2200 146,000-186,000

[0085] Advantageously, the thermoplastic resin may be chosen from the group comprising ethylene-vinyl acetate of formula III:

##STR00005##

wherein n and m are integers and the ethylene-vinyl acetate has content of vinyl acetate from 15 to 50 wt-%, preferably from 14 to 32 wt-% or from 17 to 42 wt-%.

[0086] Advantageously, the two-steps curable composition according to the invention, may further comprise one or more additive(s), preferably chosen in the group comprising an organic solvent, a filler, a dye, mixed elastomer epoxy resin, rubber and mixtures thereof.

[0087] Advantageously, the organic solvent may be chosen from the group comprising alcohols such as ethanol, isopropanol, n-propanol, isobutyl alcohol and n-butyl alcohol, methoxypropanol, methoxyethanol, aromatic solvents, such as benzene, toluene or xylene, ketones such as acetone or methyl ethyl ketone, ethereal solvents, such as diethyl ether compounds or an ester such as ethyl acetate, n-butyl acetate or ethyl propionate. Solvents may be used alone or in combination.

[0088] Advantageously, the filler may be any fine inert mineral powder, at least 85% of the elements of which have a dimension of less than 0.08 mm, such as an additives in certain cements or to improve the workability and compactness of mortars and concretes. Suitable fillers may be chosen from the group comprising calcium carbonate, kaolin, talc, wollasonite, mica, silica, carbon black, dolomite, barium sulfate, ATH, MDH, diatomaceous earth, magnetite, hematite, halloysite, zinc oxide, titanium dioxide, metal oxides, ceramics (such as SiO.sub.2, Al.sub.2O.sub.3) and mixtures thereof.

[0089] Advantageously, the dye may be chosen in the group comprising flavine, cyanine, xanthenic dyes, thiazines (methylene blue), acridines, N-methylacridone, phenosafranines, thiopyronines, riboflavines, phenoxazines, pyrromethenes, polymethines, fluorones, squarylium, julolidine dyes, phenoxazones, quinolinones, phtalocyanines, benzopyranones, rhodanines, crystal violet, benzofuranone derivatives, dimethyl aminostyryl benzothiazolinium iodides and mixtures thereof.

[0090] On another aspect, the invention relates to a process for preparing a prepreg comprising the steps of: [0091] 1) coating a first support with the two-steps light and heat curable composition according to the invention; [0092] 2) partially photocuring the composition on the first support, by subjecting said composition to a light emission source until a 20 to 90% conversion rate of the reactive functions of the polymerisable resin is reached; [0093] 3) optionally transferring the composition obtained in step 2) from the first support onto a second support;
and obtaining the prepreg.

[0094] Advantageously, the process according to the invention further comprises a step 4) of preparing a laminated composite, said step 4) comprising a thermocuring of the prepreg obtained in step 2) or in step 3), preferably at a temperature from 100 to 200° C., under a pressure from 0.5 to 5 MPa;

and obtaining the laminated composite.

[0095] Advantageously, the process according to the invention comprises the steps of: [0096] 1) coating a first support with the two-steps light and heat curable composition according to the invention; [0097] 2) partially photocuring the composition on the first support, by subjecting said composition to a light emission source until a 20 to 90% conversion rate of the reactive functions of the polymerisable resin is reached; [0098] 3) optionally transferring the composition obtained in step 2) from the first support onto a second support;
and obtaining the prepreg; [0099] 4) thermocuring the prepreg obtained in step 2) or in step 3), preferably at a temperature from 100 to 200° C., under a pressure from 0.5 to 5 MPa;
and obtaining the laminated composite.

[0100] It is meant herein by “prepreg” or “prepreg layer”, a pre-impregnated support with a partially photocured composition according to the invention (as obtained in step 2) or 3) of the process).

[0101] It is meant herein by “laminated composite”, an assembly of one or more thermocured prepreg(s) according to the invention (as obtained in step 4) of the process).

[0102] It is meant herein by “conversion rate”, the % of reactive functions of the polymerisable resin that have reacted, with respect to the quantity of reactive functions introduced in the composition, in the polymerisation process activated by the photoinitiating system in step 2) of the process according to the invention. Depending of the polymerisable resin, the reactive functions may be cyclic ether and/or unsaturated ethylene functions, preferably chosen in the group comprising cyclic ether, epoxy, acrylate, methacrylate, styrene, ethylene, propylene, N-vinyl acrylamide, N-vinylpyrolidone and epoxy-acrylate functions.

[0103] Advantageously, a partial photocuring according to step 2) of the process of the invention has a conversion rate from 20 to 90%, preferably from 30 to 70%, more preferably from 35 to 65%, and even more preferably from 40 to 60%. For example, when the reactive functions are epoxy, a partial photocuring according to step 2) of the process of the invention may have a conversion rate from 25 to 75%, preferably from 40 to 60%, For example, when the reactive functions are acrylate, a partial photocuring according to step 2) of the process of the invention may have a conversion rate from 20 to 90%, preferably from 40 to 80%, and even more preferably from 50 to 70%.

[0104] Advantageously, in step 2) of the process according to the invention, the light emission source may be any source that can irradiate in the wavelength range where the photoinitiating system is active. The light emission source wavelength may vary from ultraviolet to visible (i.e. from 250 to 800 nm), preferably from 300 to 500.

[0105] Advantageously, in step 2) of the process according to the invention, the light emission source may be any system emitting in the wavelength ranges mentioned above. For example, the light emission source may be a conventional UV arc lamp or microwave lamp based on mercury or mercury doped with elements such as iron or gallium or a LED source emitting a smaller wavelength spectrum, or a laser diode assembly.

[0106] Advantageously, in step 4) of the process according to the invention, the temperature of the thermocuring may be over 100° C., preferably from 100 to 200° C., and more preferably from 150 to 190° C.

[0107] Advantageously, in step 4) of the process according to the invention, the prepreg layers obtained in step 2) or in step 3) may be subjected to a pressure, preferably from 0.5 to 5 MPa, preferably from 2.5 to 3.5 MPa.

[0108] Advantageously, in step 4) of the process according to the invention the pressure and heat may be applied by continuous hot calendering systems or with a semi-continous heating-press.

[0109] Advantageously, the first support and/or the second support comprise(s) a plurality of fibers, said fibers preferably being chosen in the group comprising aromatic polyamide fibers, natural fibers, basalt fibers, carbon fibers, glass fibers, and hybrids thereof. Preferably the first support and/or the second support is made of aromatic polyamide fibers.

[0110] Advantageously, the first support and the second support may be identical or different.

[0111] Advantageously, the process according to the invention may comprise a step 3) of transferring the composition obtained in step 2) from the first support onto a second support, the first and second support being preferably different.

[0112] Advantageously, the process may not comprise any step 3).

[0113] Adavantageously, the first support and the second support may be different and the first support may comprise a polyethylene terephtalate film. In a variant of the process according to the invention, the first support may be a polyethylene terephtalate film and the second support may comprise a plurality of fibers as described above. Preferably, the first support may be a polyethylene terephtalate film and the second support may be made of aromatic polyamide fibers. In that variant of the process, the partially cured composition is transferred from the first to the second support in step 3) to obtain the prepreg.

[0114] Advantageously, the laminated composite obtained according to the process of the invention comprises one or more prepreg layers.

[0115] Advantageously, the process according to the invention may further comprise a step 3a) of superimposing at least 2 prepregs obtained in step 2) or in step 3) before carrying out step 4). In that variant, after carrying out step 4) of the process of the invention, one may obtain a multilayer laminated composite. Preferably in step 3a), from 2 to 50, more preferably from 10 to 30, prepreg obtained in step 2) or in step 3) may be superimposed.

[0116] The invention also relates to a prepreg or laminated composite obtained by the process according to the invention. The laminated composite may be composed of one or more prepregs.

[0117] The invention also encompasses a laminated composite comprising one or more prepreg layer(s), the laminated composite comprising a cured composition according to the invention and at least one support comprising a plurality of fibers, said fibers preferably being chosen in the group comprising aromatic polyamide fibers, natural fibers, basalt fibers, carbon fibers, glass fibers, and hybrids thereof.

[0118] It is mean by “cured composition” according to the invention, a two-steps light and heat curable composition that may have been polymerized in the process according to the invention.

[0119] The invention thus also include a use of a two-steps light and heat curing composition according to the invention to prepare a prepreg and a mono- or multilayer laminated composite. The invention thus also include a prepreg and a mono- or multilayer laminated composite manufacturing method comprising a step of using a two-steps curing composition of the invention.

EXAMPLES

[0120] The prepreg and laminated composite of this invention and their preparation can be understood further by the examples that illustrate some of the processes by which these materials are prepared or used. It will be appreciated, however, that these examples do not limit the invention. Variations of the invention, now known or further developed, are considered to fall within the scope of the present invention as described herein and as hereinafter claimed.

Example 1: Formulation of Ethylenically Unsaturated Based Resin

[0121] The PVB used is Mowital B 60H (Non-volatile content: ≥97,5 wt-%; content of polyvinyl alcohol, hydroxyl groups in terms of polyvinyl alcohol, 18-21 wt-%; content of polyvinyl acetate, acetyl groups in terms of polyvinyl acetate 1-4 wt-%; dynamic viscosity according to DIN 53015, at 20° C., 10% solution in ethanolcontaining 5% water: 160-260 mPa.Math.s) or B 75H (Non-volatile content: ≥97.5 wt-%; content of polyvinyl alcohol, hydroxyl groups in terms of polyvinyl alcohol, 18-21 wt-%; content of polyvinyl acetate, acetyl groups in terms of polyvinyl acetate 0-4 wt-%; dynamic viscosity according to DIN 53015, at 20° C., 10% solution in ethanolcontaining 5% water: 60-100 mPa.Math.s) from Kuraray and the acrylate resins is SR238 (6-prop-2-enoyloxyhexyl prop-2-enoate, CAS NO. 88250-32-2), SR508 (dipropylene glycol diacrylate, CAS NO. 57472-68-1) from Sartomer. Photoinitiating system used is Omnirad TPO-I from IGM (Ethyl(2,4,6-Trimethylbenzoyl)-phenyl phosphinate, CAS NO. 84434-11-7) or BAPO from Merck (Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, CAS NO. 162881-26-7).

[0122] The thermoplastic resin with solvent was added to the ethyleniccaly resin and mixed vigorously in a ultrasound bath during 2 hours and then by a stirring plate the night.

[0123] The photoinitiating system was added to the mixture and vigorously mixed.

TABLE-US-00003 TABLE 3 Sample 1 to 9. Sample reference 1 2 3 4 5 6 7 8 9 PVB 60H 66.9 66.5 47.4 66.5 56.7 66.5 75H 66.5 66.9 47.5 Acrylate SR238 28.4 29.0 47.4 47.5 28.4 37.9 28,4 Photoinitiating system SR508 29 28.4 TPO-I 5.1 4.1 4.1 5.1 5.2 5.1 5.1 4.4 BAPO 5.1

[0124] After a given reaction time, the mixture was spread onto Mylar™ film (for a thickness: 35 μm). The resin composition on the Mylar™ samples were cured using a Phoseon LED395-16W at 1000 mW/cm.sup.2 during 1 to 2 minutes. The formed film onto Mylar™ was transfered onto aramid support (Twaron™ CT736, Twaron™ T750) to obtain the prepreg. The prepreg layers were placed on top of each other and then heat-pressed at 4 MPa at 190° C. during 20 minutes.

Example 2: Formulation of Cyclic Ether Based Resin

[0125] The PVB used is Mowital B 75H or B 60H from Kuraray and epoxyde resins are DER 331 (CAS NO. 25085-99-8) or DGEBA (CAS NO. 1675-54-3) from DOW, an epoxy additive Kane Ace MX150 (KA, Bis A Epoxy, ref=MX 150, dispersed CSR type=Polybutadiene Rubber, %CSR=40+/−1 wt-%, nominal viscosity 16,000 cps@50° C., nominal EEW 310 g/eq) from Kaneka is further added. The photoinitiating system is Speedcure 938 (S938, CAS NO. 61358-25-6, Bis-(4-t-butylphenyl)-Iodonium hexafluorophosphate) from Lambson in combination wirh Isopropylthioxanthone (ITX, CAS NO. 83846-86-0) from Lamberti.

[0126] The thermoplastic resin with solvent was added to the photoinitiating system and mixed vigorously in a ultrasound bath during 2 hours and then by a stirring plate the night.

[0127] The cyclic ether resin was added to the mixture and vigorously.

TABLE-US-00004 TABLE 4 Samples 10 to 12. Sample reference 10 11 12 PVB 60 H 77.1 75 H 67.8 67.9 Epoxy DGEBA 19.87 19.3 17.6 Kane Ace 9.9 10.0 Photoinitiating S938 2.4 6.2 4.0 system ITX 0.3 1.1 1.0

[0128] After a given reaction time, the mixture was spread onto Mylar™ film (for a thickness: 50 μm). The resin composition on the Mylar™ samples were cured using a Phoseon LED395-16W at 1000 mW/cm.sup.2 during 14 minutes. The formed film onto Mylar™ was transfered onto aramid support (Twaron™ CT736, Twaron™ T750) to obtain the prepreg. The prepreg layers were placed on top of each other and then heat-pressed at 2 MPa, at 200° C. during 20 minutes.

Example 3: Measured Parameters

[0129]

TABLE-US-00005 TABLE 5 parameters. Cyclic ether based Acrylate based formulations (10-12) formulations (1-6) % Conversion On BaF2, IR tablet, On PP sheet, RT-FTIR point by point as a in Rapid Scan mode for function of irradiation time. kinetics monitoring, LED 395, 16 W, irradiation duration 120 s, 1000-1100 mW/cm.sup.2, UVW LEDave phoseon LED. 395 nm, 900 mW/cm.sup.2. Resin % and adhesion force Adhesion force measured by peeling on Instron 250 kN traction machine. 4 folds of 5.5 × 25 cm of which 10 cm between two folds are not glued to have a grip by the jaws on 5 cm. Machine parameters: 1 mm/min to 5N then 2 mm/min. The 5N are to be added to the final value. Measurement of the % resin on these folds in order to have a resin/adhesion relationship. Tg DSC Q200 TA, 10° C./min, range −10° C. to 200-250.sup.o C. Penetrated capsule. These values are those measured on polymerized film on GF when there is GF. Otherwise they are parts of polymerized films during transfer/ adhesion tests on a surface of 10 × 12 cm.

TABLE-US-00006 TABLE 6 results (good: adhesion force > 30N). Sample Conversion % Resin Adhesion Tg reference rate (%) (%) force (N) (° C.)  1 80 20 50 70.8  2 80 18 46 70  3 54 12 66 71  4 70 11 good 70  5 88 8.8 20 70  6 88 8.8 40 70  8 52 65  9 12 52 64 10 30 7.7 65 48 11 48 10 40 46

Example 4: Ballistic Tests

[0130] The impact resistance of a .22 caliber projectile and a 1.102 g mass have been tested according to Stanag 2920 standard. The result for a Twaron CT736 reinforcement gives an average V50 speed between 620 and 660 m/s for a laminate with a surface mass of 8-9 kg/m.sup.2.

TABLE-US-00007 TABLE 7 ballistic results on samples 1, 4, 7, 8, 9, 10 and 11 comprising 18 layers. Sample reference V50 (m/s)  1 638  4 636  7 641.6  8 643  9 633 10 621 11 620

LIST OF REFERENCES

[0131] [1] Jay, M. L. “A call to arms” Composites Manufacturing, January-February 2017, 16-21.

[0132] [2] Dung, J. D., Comparisons of Epoxy Technology for Protective Coatings and Linings in Wastewater Facilities, The Industrial Protective Coatings Conference and Exhibit Proceedings, SSPC 99-14, pp. 31-37.

[0133] [3] Nayak et al., Polym. Composites, 2012, 443; Gopinath et al. Composites Structures, 2012, 94, 2690; Cheeseman et al. Composite Structures, 2003, 61, 161.

[0134] [4] WO 2013/124147A1.