Hot-curable compositions containing substituted bicyclo[2,2,1]hept-5-ene-2,3 imides of dicarboxylic acids and polymalein imide.

0001EP-A-105 024 describes allyl- or methallyl-substituted bicyclo [2.2.1] hept-5-ene-2,3-dicarboximides and their use for the production of polymers by heating the imides to temperatures of 180 to 300 ° C. It is also known that polymaleimides can be converted to crosslinked products with or without the addition of crosslinking reagents such as diamines or alkenylphenols (for example US 3,562,223, 3,658,764, 3,380,964, 4,038,251 and 4,100,140).

0002When using carboximide-containing systems, such as for example in the production of composite materials and prepregs, it is desirable that the systems can be cured sufficiently quickly, are not brittle and are sufficiently sticky, have good suppleness properties in the form of thin films, a suitable gel time and have good strength and stability. The previously known systems generally do not sufficiently meet at least one of these important requirements.

0003It has now been found that significantly improved properties can be achieved if mixtures of the dicarboximides, polymaleimides, alkenylphenols or alkenylphenol ethers and triallyl isocyanurate used. These mixtures exhibit rapid curing in the presence of a curing catalyst, satisfactory flexibility, stickiness, and suppleness and gelling time, as well as good mechanical, thermal and electrical properties. The hardened systems are therefore well suited for use as high-performance composites and similar applications. These composites also form an important part of the present invention.

0004The present invention relates to heat-curable mixtures of substances<ul id="ul0001" list-style="none"><li>a) at least one compound of formula 1<chemistry id="chem0001" num="0001"><img file="EP0235084A2_D0001.tif" /></chemistry></li><li>b) at least one compound of formula II<chemistry id="chem0002" num="0002"><img file="EP0235084A2_D0002.tif" /></chemistry></li><li>c) at least one alkenylphenol or an alkenylphenol ether and</li><li>d) triallyl isocyanurate,</li></ul>where in formulas I and II n is 1 or 2 and m is 2 or 3, R, when n is 1, hydrogen, C₁-C₁₂-Alkyl, C₃-C₆Alkenyl, Cs-Cs-cycloalkyl, C₆-C_lo-aryl or benzyl, or when n is 2, -C_pH_2p-, where p is an integer from 2 to 20, or C₆-C₁₀Arylene or a group of formula III<chemistry id="chem0003" num="0003"><img file="EP0235084A2_D0003.tif" /></chemistry>where T is methylene, isopropylidene, -CO-, -0-, -S- or -SO₂- means R 'is an m-valent organic radical with 2 to 30 carbon atoms and R_i, R₂ and R₃ are independently a hydrogen atom or a methyl group.

0005Preferably R_i and R₂ one hydrogen atom each.

0006R can be a straight-chain or branched C₁-C₁₂Alkyl group, such as methyl, ethyl, isopropyl, n-butyl, isopentyl, n-hexyl, 2-ethylhexyl, n-decyl and n-dodecyl, but preferably a C.₁-C₈-Alkyl group. If RC₃-C₆-Alkenyl, this radical can also be straight-chain or branched, and is, for example, allyl, methallyl, 2-butenyl or 3-hexenyl, allyl being preferred. When R is a cycloalkyl group it can mean cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl, with cyclohexyl being preferred.

0007When R represents an aryl group, it can represent an unsubstituted or a phenyl group substituted by one or two methyl groups, such as tolyl or xylyl, or can mean naphthyl. R is preferably phenyl. If R is a -C_pH_2pGroup, it can be straight-chain or branched, for example ethylene, propylene, trimethylene, tetramethylene, hexamethylene, octamethylene and dodecamethylene. R is preferably a - (CH₂)_pGroup, with p equal to 2 to 12. If R is a group of the formula III, this is preferably bonded in the 4,4'-position to the nitrogen atoms.

0008If R is a C₆-C_lrepresents o-arylene group, it can be a 1,3-naphthylene, 1,4-naphthylene, 1,5-naphthylene or 2,6-naphthylene or preferably an m-phenylene or p-phenylene group .

0009When R represents a group of formula III, T is preferably a methylene group, -0- or -SO_e.g.-.

0010Compounds of the formula I in which R₁ and R₂ are each a hydrogen atom and R, when n is 1, hydrogen, C₁-C₈Alkyl, allyl, cyclohexyl, phenyl or benzyl, or when n is 2, R - (CHz) - with p = 2 to 12, m- or p-phenylene, or a group of the formula III in which T is a methylene group, Is -0- or -SOz-.

0011Particularly preferred compounds of the formula I are those in which R₁ and R_e.g. are each a hydrogen atom and R, when n is 1, allyl, or when n is 2, - (CH_e.g.)₆- or<chemistry id="chem0004" num="0004"><img file="EP0235084A2_D0004.tif" /></chemistry>means.

0012Most preferred are mixtures according to the invention which contain as component (a) N-allyl-allylbicyclo [2.2.1] hept-5-en-2,3-dicarboximide, bis [4- (allylbicyclo) [2.2.1] hept -5-en-2,3-dicarboximidophenyl} methane and N, N'-hexamethylene-bis (allylbicyclo) [2.2.1] hept-5-en-2,3-dicarboximide or mixtures of these compounds.

0013Examples of specific compounds of the formula I are:<ul id="ul0002" list-style="none"><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-methylimide,</li><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-allylimide,</li><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid N- (2-ethylhexyl) imide,</li><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-cyclohexylimide,</li><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-phenylimide,</li><li>Allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-benzylimide,</li><li>N, N'-ethylene-bis- (allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid imide),</li><li>N, N'-hexamethylene-bis- (allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),</li><li>N, N^I-Dodecamethylene-bis- (allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),</li><li>Bis- [4- (allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] methane,</li><li>Bis [4- (methallyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] methane,</li><li>N, N'-p-phenylene-bis (allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide,</li><li>Bis [4- (allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] ether,</li><li>Bis [4- (allyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] sulfone,</li><li>Allyl-methyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-allylimide, allyl-methyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N- (2-ethylhexyl) imide,</li><li>Allyl-methyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboxylic acid-N-phenylimide, N, N'-hexamethylene-bis- (allyl-methyl-bicyclo [2.2.1] hept-5- en-2,3-dicarboximide),</li><li>Bis [4- (allyl-methyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] methane and</li><li>Bis [4-methallyl-methyl-bicyclo [2.2.1] hept-5-en-2,3-dicarboximidophenyl)] sulfone.</li></ul>

0014The imides of the formula I can be prepared in a manner known per se, for example analogously to the process described in EP-A-105 024, by reacting an anhydride of the formula IV<chemistry id="chem0005" num="0005"><img file="EP0235084A2_D0005.tif" /></chemistry>with a compound of formula V<chemistry id="chem0006" num="0006"><img file="EP0235084A2_D0006.tif" /></chemistry>where R, R₁, Rz and n have the meaning given under formula I, are produced at elevated temperature and with distillation of the water formed in the reaction. If the compounds of the formula V are ammonia or low-boiling monoamines, an excess of these reactants is recommended. Diamines are advantageously used in a stoichiometric ratio. The reaction can be carried out without a solvent or in the presence of an inert solvent which can be used for the azeotropic removal of the water (entrainer). The temperature of the reaction can be between 100 and 250 ° C. The imides of the formula I are preferably produced in the melt at a pressure of at most 4500 Pa at temperatures between 130 and 220 ° C., in particular 180 and 220 ° C.

0015Possible organic radicals R 'when m = 2 are, for example: -C_pH_2p- with p = 2-20, especially - (CH₂)_p- with p = 2-12, -CH₂CH₂SCH₂CH₂-, Arylene with 6-10 C atoms, xylylene, cyclopentylene, cyclohexylene, 1,4-bis (methylene) cyclohexylene, the rest of the bicyclohexylmethane or residues of the formulas VI or VII<chemistry id="chem0007" num="0007"><img file="EP0235084A2_D0007.tif" /></chemistry>

0016If m represents the number 3, R 'means, for example, a radical of the formula VIII<chemistry id="chem0008" num="0008"><img file="EP0235084A2_D0008.tif" /></chemistry>the N, N ', N "trismaleinimide of tris (4-aminophenyl) phosphite and the N, N', N" trismaleinimide of tris (4-aminophenyl) thiophosphate.

0017Preferred compounds of the formula II are those in which m is the number 2, R₃ a hydrogen atom and R '- (CHz) - with p = 2-12, m- or p-phenylene, m- or p-xylylene, 1,4-cyclohexylene, 1,4-bis (methylene) -cyclohexylene, the rest of 4,4'-biscyclohexylmethane and especially a radical of the formula VII which is bonded in the 4,4'-position, in which Qi and Q₂ one hydrogen atom each and T₁ 0, CH₂ or so₂ represent. N, N ', 4,4'-diphenylmethane bismaleimide is very particularly preferred.

0018According to the invention, allylphenols and methallylphenols or their ethers are preferably used as alkenylphenols or alkenylphenol ethers. Mono- or polynuclear, preferably binuclear, alkenylphenols and alkenylphenol ethers can be used. At least one core preferably contains both an alkenyl group and an optionally etherified phenolic OH group.

0019As is known, alkenylphenols can be prepared by rearrangement of the corresponding alkenyl ethers of the phenols (for example the allyl ether of the phenol) by heating (Claisen rearrangement). The alkenyl ethers are also prepared in a known manner by reacting the phenols with, for example, allyl chloride in the presence of an alkali metal hydroxide in solvents.

0020Typical examples are compounds of the formulas IX-XII:<ul id="ul0003" list-style="none"><li>Compounds of formula IX<chemistry id="chem0009" num="0009"><img file="EP0235084A2_D0009.tif" /></chemistry>In the above formulas VI to VIII, T means₁ Methylene, isopropylidene, CO, 0, S, SO₂, -P = O (Q₃), -NQ₃- (Q₃ = C₁-C₄-Alkyl), -NN-, -CONH-, -COO-, -NQ₃-CO-X-CO-NQ₃-, -O-CO-X-CO-O-,<chemistry id="chem0010" num="0010"><img file="EP0235084A2_D0010.tif" /></chemistry></li><li>q is 0 or 1,</li><li>Z represents O or S,</li><li>Q₁ and Q₂ independently of one another represent a halogen atom, especially chlorine or bromine, methyl or ethyl and in particular a hydrogen atom,</li><li>_X is the direct bond, _-CtH2t- with t = ₁-₁₂, Arylene with 6-10 C atoms, xylylene, cyclopentylene or cyclohexylene and R₃ has the meaning given above.</li></ul>

0021The following may be mentioned as specific examples of maleimides of the formula II which may be present in the mixtures according to the invention:<ul id="ul0004" list-style="none"><li>N, N'-ethylene-bis-maleimide,</li><li>N, N'-hexamethylene-bis-maleimide,</li><li>N, N'-m-phenylene-bis-maleimide,</li><li>N, N'-p-phenylene-bis-maleimide,</li><li>N, N'-4,4'-diphenylmethane-bis-maleimide,</li><li>N, N'-4.4^t-3,3'-dichloro-diphenylmethane-bis-maleimide,</li><li>N, N'-4,4'-diphenylether-bis-maleimide,</li><li>N, N'-4,4'-diphenylsulfone-bis-maleimide,</li><li>N, N'-m-xylylene-bis-maleimide,</li><li>N, N'-p-xylylene-bis-maleimide,</li><li>N, N'-4,4'-2,2-diphenylpropane bis-maleimide,</li><li>the N, N'-bis-maleimide of 4,4'-diamino-triphenylphosphate,</li><li>the N, N'-bis-maleimide of 4,4'-diamino-triphenylphosphite,</li><li>the N, N'-bis-maleimide of 4,4'-diamino-triphenylthiophospha_ts,</li><li>the N, N ', N "trismaleinimide of tris (4-aminophenyl) phosphate,</li></ul>

0022where T is the direct bond, methylene, isopropylidene, 0, S, SO or SO₂ means.

0023Propenyl substituted phenols of formula X<chemistry id="chem0011" num="0011"><img file="EP0235084A2_D0011.tif" /></chemistry>where R₄, Rs and R₆ independently represent a hydrogen atom, an allyl or propenyl group, at least one of R₄ to R₆ represents an alkenyl group, preferably the propenyl group.

0024Compounds of formula XI<chemistry id="chem0012" num="0012"><img file="EP0235084A2_D0012.tif" /></chemistry>where R₄, R₅, R₆ and R₇ independently of one another a hydrogen atom, or a C₃-C₄-Alkenyl, preferably an allyl or propenyl group, at least one of R₄ to R₇ stands for the propenyl group and T is the direct bond, methylene, isopropylidene, -0-, -S-, -SO- or -SO₂- means.

0025Compounds of formula XII<chemistry id="chem0013" num="0013"><img file="EP0235084A2_D0013.tif" /></chemistry>

0026wherein Re, R₉, Rio, R₁₁, R₁₂ and R₁₃ independently of one another denote a hydrogen atom, alkyl with 1-4 C atoms, alkenyl with 3-4 C atoms, preferably allyl or propenyl, where at least one of R_s to R₁₃ represents an alkenyl, preferably allyl or propenyl group and a represents a value from 0 to 10. Ethers of the compounds of the formulas IX, X, XI and XII, which have at least one -OR₃-Rest included, are used, where R₃ C.₁-C₁₀-Alkyl, C₆-C₁₀-Aryl or C₃-C₆-Alkenyl, preferably allyl or methallyl. Compounds of the formula XI in which R₄ and R₆ one propenyl group each and Rs and R₇ each represent a hydrogen atom and T represents methylene, isopropylidene or 0.

0027According to the invention, it is also possible to use isomer mixtures of propenyl- and allyl-substituted mono- and polyhydric phenols. Mixtures of propenyl- and allyl-substituted phenols of the formula IX are preferably used, in particular those of the formula IXa<chemistry id="chem0014" num="0014"><img file="EP0235084A2_D0014.tif" /></chemistry>where T is methylene, isopropylidene or 0.

0028Good results are also achieved with mixtures of polynuclear alkenylphenols and / or alkenylphenol ethers with mononuclear alkenylphenols and / or alkenylphenol ethers.

0029Mixtures of compounds which contain only one OH group and only one alkenyl group per aromatic ring, with compounds which have several OH groups and / or several alkenyl groups per aromatic ring, or mixtures of the corresponding phenyl ethers of these compounds can also be used.

0030Such alkenyl-substituted phenols and polyols are described, for example, in US 4,100,140 and US 4,371,719.

0031Typical connections include, for example o, o'-Diallylbisphenol A, 4,4'-dihydroxy-3,3'-diallylbiphenyl, bis (4-hydroxy-3-allylphenyl) methane, 2,2-bis (4-hydroxy-3,5- diallylphenyl) propane, eugenol (4-allyl-2-methoxyphenol), o, o'-dimethallylbisphenol A, 4,4'-di-hydroxy-3,3'-dimethallylbiphenyl, bis (4-hydroxy-3-methallylphenyl) - methane, 2,2-bis (4-hydroxy-3,5-dimethallylphenyl) propane, 4-methallyl-2-methoxyphenol, 2,2-bis (4-methoxy-3-allylphenyl) propane, 2,2-bis ( 4-methoxy-3-methallylphenyl) propane, 4,4'-dimethoxy-3,3'-diallylbiphenyl, 4,4'-dimethoxy-3,3'-dimethallylbiphenyl, bis (4-methoxy-3-allylphenyl) methane, bis (4-methoxy-3-methallylphenyl) methane, 2,2-bis (4-methoxy-3 , 5-diallylphenyl) propane, 2,2-bis (4-methoxy-3,5-dimethallylphenyl) propane, 4-allylveratrol (4-allyl-1,2-dimethoxybenzene) and 4-methallylveratrol (4-methallyl-1, 2-dimethoxybenzene). O, o'-Diallylbisphenol A is particularly preferred.

0032The amount of component (a) is preferably 30 to 45% by weight, component (b) 20 to 40% by weight, component (c) 11 to 22% by weight and component (d) 12 to 16% by weight. % based on the total weight of the mixture. Particularly preferred concentrations are 30 to 32% by weight (a), 36 to 39% by weight (b), 12 to 14% by weight (c) and 13 to 15% by weight (d). When the three preferred dicarboximides mentioned above are used, they are used in a weight ratio of 3: 2: 1 and in particular 2.7: 1.7: 1.

0033The mixtures of substances according to the invention can be produced in a manner known per se by grinding and blending or by melting the components. This typically happens at temperatures from 90 to 140 ° C.

0034The mixtures of substances can be cured or processed in an inert organic solvent, but preferably from the melt. The substance mixtures can be hardened as such. However, the mechanical properties of the cured products are improved if the curing takes place in the presence of a curing catalyst. Suitable inert organic solvents are, for example N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, toluene, xylenes, methyl ethyl ketone and ethylene glycol monoalkyl or dialkyl ether with 1-4 C atoms in the alkyl groups. Depending on the type of component c) used and the intended use, suitable curing catalysts are, for example, organic peroxides, such as di-tert-butyl peroxide, dicumyl peroxide or tert-butyl perbenzoate, or basic catalysts, especially primary, secondary and tertiary amines, such as, for example Diethylamine, tributylamine, triethylamine, benzylamine, N, N, N ', N'-tetramethyl-4,4'-diaminodiphenylmethane, N, N-diisobutylaminoacetonitrile, and heterocyclic bases such as quinoline, N-methylpyrrolidine and imidazole. Basic catalysts of the type mentioned are preferred. Hardening is generally carried out at temperatures between 150 and 350 ° C., especially 180 and 300 ° C.

0035The mixtures of substances according to the invention are low-melting solid resins or liquid resins and are distinguished by high reactivity and good thermal and mechanical properties of the products hardened therewith, such as good flexural, shear and interlaminar shear strength. Products obtained in this way have good mechanical, thermal and electrical properties and high glass transition temperatures and are not very brittle. The mixtures of substances according to the invention can also be easily applied from the melt, especially without the addition of low-volatility solvents, for example for impregnation.

0036A network with a high crosslink density is formed during curing at elevated temperature. The term hardening used here therefore means the conversion of mixtures into insoluble and non-meltable cross-linked products, with simultaneous shaping into shaped articles such as castings, pressed bodies, laminates, or to two-dimensional structures, such as coatings, enamels and adhesive bonds. The coatings produced with the modified systems stand out, for example characterized by increased toughness. The substance mixtures according to the invention can be mixed with the customary modifiers, such as extenders, fillers and reinforcing agents, pigments, dyes, organic solvents, plasticizers, agents for improving the dry tackiness (tackifiers), rubbers, accelerators, thinners etc. in every processing phase before curing. Extenders, reinforcing agents, fillers and pigments come, for example in question: coal tar, bitumen, glass fibers, boron fibers, carbon fibers, cellulose, polyethylene powder, polypropylene powder, mica, asbestos, quartz powder, gypsum, antimony trioxide, bentone, silicon dioxide airgel ("Aerosil"), lithopone, barite, titanium dioxide, carbon black, graphite, iron oxide or Metal powder such as aluminum powder or iron powder. The curable mixtures of substances can also contain other conventional additives, such as, for example Flame retardants, thixotropy agents, leveling agents, such as silicones, cellulose acetate butyrate, polyvinyl butyrate, waxes, stearates and the like (which are also used in part as mold release agents) are added.

0037If the compositions according to the invention are used, for example, as adhesive formulations, carboxyl-terminated acrylonitrile-butadiene rubber, modification resins such as triglycidyl-p-aminophenol and accelerators such as boron trifluoride-monoethylamine complexes or imidazole complexes can also be added.

0038The present invention therefore also relates to products obtainable by curing the compositions according to the invention and laminates obtainable by heating a material impregnated with the composition according to the invention.

0039The compositions according to the invention described can be used in various fields, such as, for example, in composites, printed circuit boards, castings, moldings, adhesives and coatings. Of particular interest is their application for the production of high-performance composites, which are very important, for example, in the aviation industry. The modified resins can thus be used for the pre-impregnation of various fibrous material which is used as a top layer for honeycomb structures or as structural parts. Methods for producing prepregs are known to the person skilled in the art. For example, graphite, glass or Kevlar can be used as fibrous materials. Processes for the production of laminates are also known. Laminates of various thicknesses can, for example can be produced by press molding or autoclave molding. The compositions according to the invention can also be used successfully as hat-imparting substances.

0040The following examples describe some preferred embodiments of the present invention.

0041Example 1: A typical mixture of substances according to the invention is obtained by mixing together 25 g of N, N'-hexamethylene-bis (al) ylbicyclo [2.2.1.] - hept-5-ene-2,3-dicarboximide), 40 g of triallyl isocyanurate, 35 g of 2,2'-bis (4-hydroxy-3-allylphenyl) propane and 15 g of N-allyl-allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide in an aluminum can. The mixture is heated to 95 ° C on a hot plate and mixed with an air powered propeller stirrer. 100 g Crushed bismaleimide (eutectic bismaleimide mixture from technochemistry, sold under the name "C-353") are added to the mixture in small portions. The mixture of substances is kept at 95 ° C. for 20 minutes and stirred continuously. The temperature is raised to 135 ° C. and 40 g of powdered N, N'-4,4'-diphenylmethane-bis (allyl-bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide are dissolved in small amounts Portions added. The mixture is then stirred for a further 15 minutes at the stated temperature, cooled to 115 ° C. and filtered through a two-layer tricot filter. The resulting mixture is a homogeneous, high-flow liquid at 115 ° C.

0042Examples 2 and 3: Example 1 is repeated using the following components:<tables id="tabl0001" num="0001"><img file="EP0235084A2_D0015.tif" /></tables>

0043The mixtures obtained are homogeneous, highly flowing, amber-colored liquids at 115 ° C.

Example 4: Production of the laminates

0044A unidirectional graphite prepreg is made from the Thornel T-500 graphite fiber (Union Carbide) using pressure and heat on a UD machine. This results in a prepreg with acceptable flexibility and stickiness. The prepreg is cut, layered on top of each other to form the laminate, cured in an autoclave using the vacuum bag method and then cured in the oven. The laminate in the vacuum bag is placed in an autoclave under vacuum at room temperature. A pressure of 0.6 MPa (85 psi) is applied to the sack and the autoclave is equilibrated for 15 minutes at room temperature. Then heating is carried out at a speed of 1.7 ° C./min until the temperature of 80 ° C. is reached. The vacuum is vented and the autoclave is kept under pressure at 80 ° C. for 2 hours. At the end of the second hour, the mixture is heated again to 175 ° C. at 1.7 ° C./min and this temperature is maintained for 4 hours. The autoclave is allowed to cool for 1 1/2 hours, the pressure is released and the laminates are removed from the autoclave and from the vacuum bag.

0045The post-curing of the laminates takes place free-standing in an oven for 4 hours at 245 ° C with a heating rate of about 3 ° C / min. The post-cured laminates are cut into test specimens and tested. The resin content of the laminates is 27 to 28 Gew.X.

Test methods

0046The hardened substance mixtures are tested with thermomechanical analysis (TMA) (penetration method, heating rate 10 ° C / min, test specimen 0.86 x 1.24 mm). The glass transition temperature Tg can be seen from the table.

0047With each of the systems described above, 15 layers of the prepreg are used to produce 0 ° laminate panels. Test specimens for the shear strength in the short bending test and 0 ° and 90 ° bending test specimens are produced from these laminates. The short bending test is carried out according to ASTM D-2344 at room temperature and at 175 ° C. The 0 ° and 90 ° bending properties are tested according to ASTM D-790 at room temperature and at 175 ° C. The results are shown in the table.

0048In addition, the fracture toughness [according to the Journal of Material Science Letters, 511-515 (1982)] and the edge delamination are tested. The G1C test is measured with test specimens measuring 76 x 38 mm. The 0 ° laminate board for this test has 12 layers. The edge delamination test is carried out with laminate panels with the following sequence when layering prepregs [(± 25)₂/ 90) s. The results are as follows:

0049<tables id="tabl0002" num="0002"><img file="EP0235084A2_D0016.tif" /></tables>

0050The results show the improved performance properties of the substance mixtures according to the invention.