JPH10292096A - Resin composition for prepreg - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin compsn. which is excellent in storage stability and can give a fiber-reinforced composite material excellent in mechanical properties and corrosion resistance by compounding a (meth)acrylic acid-adduct of an epoxy resin with a peroxide as the essential ingredients. SOLUTION: A vinyl ester resin and an epoxy acrylate resin are examples of a (meth)acrylic acid-adduct of an epoxy resin. Such a resin is usually obtd. by reacting an epoxy resin with (meth)acrylic acid at 30-150 deg.C in the presence of a catalyst and an antioxidant and in the absence or presence of a solvent. The amt. of (meth)acrylic acid reacted is usually 1-5 equivalents based on 1 equivalent of epoxy group. Pref., thus obtd. resin has a number average mol.wt. of 400-5,000. The amt. of the peroxide compounded is usually 1-10 wt.% of this resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for prepreg, and more particularly, to a fiber-reinforced composite material obtained by combining the resin composition with a reinforcing fiber while maintaining storage stability. The present invention relates to a prepreg resin composition capable of obtaining a composite material having excellent mechanical properties and corrosion resistance.

[0002]

2. Description of the Related Art Composite materials comprising a reinforcing fiber and a matrix resin are widely used in sports equipment, aerospace, and general industrial applications because of their light weight and excellent mechanical properties. Various methods are used for producing a fiber-reinforced composite material, and a method using a prepreg, which is a sheet-like intermediate substrate in which a reinforcing fiber is impregnated with a matrix resin, is widely known. In this method, after laminating a plurality of prepregs, the formed laminate is heated to obtain a composite material molded product.

As the matrix resin used for the prepreg, both thermosetting resins and thermoplastic resins are used. In most cases, a thermosetting resin excellent in handleability, particularly an epoxy resin, is used. Although the thermosetting resin is also used as a matrix resin, such as a combination of a maleimide resin, a cyanate resin, etc., it has excellent storage stability, and furthermore, when combined with a reinforcing fiber to form a fiber-reinforced composite material, A prepreg resin composition capable of obtaining a composite material having sufficiently excellent mechanical properties and corrosion resistance has not been obtained so far.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a prepreg having excellent storage stability and a fiber reinforced composite material obtained by laminating and curing the prepreg to obtain mechanical properties. An object of the present invention is to provide a prepreg resin composition which is excellent in corrosion resistance.

[0005]

As a result of studying the above problems, the present inventor has found that the use of a resin composition containing a resin in which a specific acid is added to an epoxy resin and a peroxide has led to these problems. And found that the present invention was completed.

That is, the present invention relates to a resin composition for prepreg containing (A) a resin obtained by adding acrylic acid and / or methacrylic acid to an epoxy resin and (B) a peroxide as an essential component.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Resins obtained by adding acrylic acid and / or methacrylic acid to an epoxy resin used as the component (A) of the present invention generally include vinyl ester resins and epoxy acrylate resins. Can be obtained by reacting an epoxy resin with acrylic acid and / or methacrylic acid.

The number average molecular weight of a resin obtained by adding acrylic acid and / or methacrylic acid to an epoxy resin is 40
It can be 0 to 5000. Number average molecular weight is 40
If it is less than 0, the resin composition for prepreg containing the resin drips, and it is difficult to set Vf (fiber volume content) and Vm (matrix resin volume content) to desired values.
On the other hand, when the number average molecular weight exceeds 5000, it is difficult to impregnate the reinforcing fiber with the resin composition for prepreg containing the resin, and the handleability is poor.

In this case, the epoxy resin is usually added with an antioxidant in the presence of a catalyst, and in the presence or absence of a solvent, usually at 30 to 150 ° C., preferably 30 to 150 ° C.
Acrylic acid and / or methacrylic acid are reacted with epoxy resin in a temperature range of 0 ° C., and vinyl ester resin,
An epoxy acrylate resin or the like can be obtained.

The amount of the acrylic acid and / or methacrylic acid to be added can be generally 1 to 5 chemical equivalents with respect to 1 chemical equivalent of the epoxide group of the epoxy resin, preferably the acrylic acid and / or methacrylic acid is added. The addition of methacrylic acid can be performed until the acid value becomes 1 mg / KOH or less, and it is preferable that all the epoxide groups in the epoxy resin react with the acrylic acid and / or methacrylic acid.

The epoxy resin used in the reaction includes bisphenol A type epoxy resin; bisphenol F type epoxy resin; bisphenol S type epoxy resin;
Bisphenol B type epoxy resin; naphthalene type epoxy resin; novolak type epoxy resin; epoxy resin having a fluorene skeleton; epoxy resin made from a copolymer of phenol compound and dicyclopentadiene; diglycidyl resorcinol, tetrakis (glycidyloxyphenyl) Glucidyl ether type epoxy resins such as ethane and tris (glycidyloxyphenyl) methane; glycidylamine type epoxy resins such as tetraglycidyldiaminodiphenylmethane, triglycidylaminophenol, triglycidylaminocresol and tetraglycidylxylenediamine, and mixtures thereof And the like.

Examples of the catalyst used in the reaction include amines, amine salts, inorganic hydroxides, organic metals, and organic phosphorus compounds. Tertiary amines having an alkyl group having 3 to 10 carbon atoms and salts thereof. And the like are preferably used. Specific examples of the catalyst include triethylamine, benzyldimethylamine, N, N-dimethylbenzylamine,
Examples include dimethylaniline, methyltriethylammonium chloride, triethylbenzylammonium chloride, benzyltrimethylammonium hydroxide, triphenylstibine, triphenylphosphine, potassium hydroxide and the like. The addition amount of the catalyst can be usually 0.1 to 10 parts by weight based on 100 parts by weight of the epoxy resin and acrylic acid and / or methacrylic acid.

Examples of the antioxidant used in the above reaction include a phenolic antioxidant, a sulfuric antioxidant, and a phosphorus-based antioxidant, and a phenolic antioxidant is preferred. Di-t-butyl-p-cresol, hydroquinone, methoquinone, butylated hydroxyanisole and the like can be used.

The solvent used in the reaction can be appropriately selected depending on the reaction temperature, and specifically, ethyl cellosolve,
Butyl cellosolve acetate, ethyl cellosolve acetate, methyl ethyl ketone, carbitol acetate,
Organic solvents such as isopropyl cellosolve acetate, diethylene glycol dimethyl ether, and solvent naphtha or styrene, vinyl acetate, N-vinylpyrrolidone, butyl acrylate, carbitol methacrylate, carbitol acrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, and tripropylene glycol diacrylate 1,6-hexane dimethacrylate, tripropylene glycol dimethacrylate, 1,6-hexane diacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate, tri Methylol propane triacrylate, trimethylol B pan trimethacrylate, tris (hydroxyethyl) isocyanurate trimethacrylate, dipentaerythritol hexa methacrylate, tris (hydroxyethyl) isocyanurate triacrylate, or the like can be used dipentaerythritol hexaacrylate.

Specific examples of the resin obtained by adding acrylic acid to an epoxy resin include VR-60 and VR-90 (both are trade names, manufactured by Showa Kogyo Co., Ltd.) and YDV-1128N (trade name, manufactured by Toto Kasei Co., Ltd.) ) Are commercially available. The peroxide of the component (B) used in the present invention includes:
It can be used in an amount of 1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the component (A).

Examples of the peroxide include organic peroxides and inorganic peroxides. Examples of the organic peroxide include ketone peroxides, diacyl peroxides, hydroperoxides, dialkyl peroxides, and the like. Examples include peroxyketals, alkyl peresters, peroxycarbonates, succinic peroxide and mixtures thereof, and examples of inorganic peroxides include potassium persulfate and ammonium persulfate.

Examples of the ketone peroxides include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, and mixtures thereof. Examples of diacyl peroxides include isobutyl peroxide, 3,5,5, -trimethylhexanoyl peroxide, lauroyl peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and acetylcyclohexanesulfonyl. Peroxides and mixtures thereof.

Hydroperoxides include t-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-
-Methane hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 1,1,3,
Examples include 3-tetramethylbutyl hydroperoxide and a mixture thereof.

As the dialkyl peroxides, di-
t-butyl peroxide, t-butyl-α-cumyl peroxide, di-α-cumyl peroxide, 1,4
-Bis (t-butyloxy) isopropylbenzene,
1,3-bis (t-butyloxy) isopropylbenzene, 2,5-dimethyl-2,5-bis (t-butyl
Oxy) hexane, 2,5-dimethyl-2,5-bis (t-butylperoxy) -3-hexyne and mixtures thereof.

The peroxyketals include 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (t-butylperoxy) valerate, , 2-bis (t-butylperoxy) butane and mixtures thereof.

Examples of the alkyl peresters include t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxy piotoate, t-butyl peroxy pivalate, and t-butyl peroxy neodecanoate. , T-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane And mixtures thereof.

As the peroxycarbonates, bis-
(2-ethylhexyl) peroxycarbonate, diisopropylperoxydicarbonate, di-sec-butylperoxydicarbonate, di-n-propylperoxydicarbonate, bis-3-methoxybutyl) peroxydicarbonate, bis (2-ethoxy) Ethyl) peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, OO-t-butyl-O-isopropylperoxycarbonate, and mixtures thereof.

In the resin composition for prepreg of the present invention, a thermoplastic resin can be used in combination. Examples of the thermoplastic resin include phenoxy resin, polyvinyl formal resin, polyvinyl butyral resin, polysulfone, polyether sulfone, and polyetherimide. , Aromatic polyesters, polyamides, various elastomers, and mixtures thereof.

The amount of the thermoplastic resin to be added is generally 5 to 25 parts by weight, preferably 10 to 20 parts by weight, per 100 parts by weight of the components (A) and (B). In the resin composition for prepreg of the present invention, a compound having an unsaturated double bond having radical polymerizability can be added to the composition for adjusting the viscosity of the composition.

Specific examples of the compound include acrylic acid,
Examples include methacrylic acid, acrylates, methacrylates, styrene, vinyltoluene, divinylbenzene, and mixtures thereof.

The amount of the compound is not particularly limited.
It can be added so that the viscosity of the resin composition of the present invention at 25 ° C. is usually in the range of 20,000 to 200,000 P. The resin composition of the present invention can be impregnated into reinforcing fibers to form a prepreg. As the reinforcing fiber, glass fiber, carbon fiber, aramid fiber, boron fiber, alumina fiber, silicon carbide fiber and the like can be used, and carbon fiber is particularly preferably used. Examples of the form of the reinforcing fiber include a long fiber sheet, a tow, a woven fabric, a mat, a knit, a braid, and the like aligned in one direction.

[0027]

Example 1 30 parts by weight of YDV-1128N (trade name, vinyl ester resin manufactured by Toto Kasei Co., Ltd.), 70 parts by weight of VR90 (trade name, vinyl ester resin manufactured by Showa Polymer Co., Ltd.) and di-α
-3 parts by weight of cumyl peroxide were mixed at 70 ° C to obtain a resin composition for prepreg. The composition was allowed to stand at room temperature (20 ° C.) for one month in order to examine the storage stability, but was not cured and was stable.

This resin composition was treated with PAN-based carbon fiber T80.
0H (trade name, manufactured by Toray Industries, Inc.) to obtain a unidirectional prepreg. Sixteen layers of this prepreg are laminated to form a laminate, and the laminate is hermetically sealed and degassed, and is cured in an autoclave at 100 ° C. for 2 hours and further at 180 ° C. for 2 hours, and is reinforced with unidirectional carbon fiber. A resin (UD-CFRP) plate (thickness: 2 mm, Vf: 60%) was obtained. The bending test of this CFRP plate was performed according to ASTM D790. The value obtained is that the bending strength in the fiber direction (0 ° direction) is 160 kg.
/ Mm ² and the flexural modulus was 15 × 10 ³ kg / mm ² .

The CFRP board was immersed in 2.5% sodium hypochlorite for 10 months, and the CFRP board was taken out and subjected to a bending test again. There was no change in the weight of the board. Separately, the CFRP plate is placed in 5% ammonia water for 10 minutes.
When the CFRP plate was immersed for a few months, the CFRP plate was taken out and subjected to a bending test again. As a result, there was no change in the flexural modulus and no change in the weight of the CFRP plate after the immersion test.

Example 2 80 parts by weight of VR60 (trade name, manufactured by Showa Kogaku KK, vinyl ester resin), and VR90 (trade name, manufactured by Showa Kogaku KK)
20 parts by weight of a vinyl ester resin) and 5 parts by weight of t-butyl peroxybenzoate were mixed at 80 ° C. to obtain a resin composition for prepreg. The composition was allowed to stand at room temperature (20 ° C.) for one month in order to examine the storage stability, but was not cured and was stable.

This resin composition was used as a PAN-based carbon fiber M40.
J (trade name, manufactured by Toray Industries, Inc.) to obtain a unidirectional prepreg. The prepreg is laminated 16 layers to form a laminate, and the laminate is sealed and degassed, and cured in an autoclave at 100 ° C. for 3 hours and further at 150 ° C. for 2 hours, and a UD-CFRP plate ( (Thickness: 2 mm, Vf: 60%)
I got

The bending test of this CFRP plate was performed according to ASTM D
790. The value obtained is the fiber direction (0 °
Direction), the bending strength was 115 kg / mm ² , and the flexural modulus was 19.5 × 10 ³ kg / mm ² .

When this CFRP plate was immersed in 2.5% sodium hypochlorite for one year, the CFRP plate was taken out and subjected to a bending test again. There was no change in the weight of the board.

Separately, the CFRP board was immersed in 5% aqueous ammonia for one year, and the CFRP board was taken out and subjected to a bending test again. There was no change in the weight of the CFRP plate after the test.

Comparative Example 1 As an epoxy resin, 13 parts by weight of Epicoat 828 (trade name, manufactured by Yuka Shell Epoxy), 30 parts by weight of YD-011 (trade name, manufactured by Toto Kasei), YDF170 (trade name, manufactured by Toto Kasei) 15 parts by weight, 40 parts by weight of YDCN701 (trade name, manufactured by Toto Kasei Co., Ltd.), 4 parts by weight of dicyandiamide, and 3 parts by weight of dichlorophenyldimethylurea.
C. to obtain a resin composition for prepreg. The composition was allowed to stand at room temperature (20 ° C.) for one month in order to examine the storage stability, but was not cured and was stable.

The same carbon fibers as in Example 1 were impregnated with the resin composition to obtain a unidirectional prepreg. This prepreg is 1
A laminate is formed by laminating six layers, and the laminate is sealed and degassed, and cured in an autoclave at 130 ° C. for 1 hour to obtain a CFRP plate (thickness: 2 mm, Vf: 60%). Was.

When a bending test was performed on this CFRP plate in the same manner as in Example 1, the bending strength was 160 kg / mm.
^{2. The} flexural modulus was 15 × 10 ³ kg / mm ² .
This CFRP plate was immersed in 2.5% sodium hypochlorite for 10 months, and the CFRP plate was taken out and subjected to a bending test again. As a result, the flexural modulus was reduced to 70% and the weight was 8%.
Diminished.

Separately, the CFRP plate was immersed in 5% ammonia water for 10 months, and the CFRP plate was taken out and subjected to a bending test again. The change in weight of the board was reduced by 10%.

[0039]

As described above, the resin composition for a prepreg containing a resin obtained by adding acrylic acid and / or methacrylic acid to an epoxy resin and a peroxide, while maintaining excellent storage stability, The fiber reinforced composite material obtained by combining the resin composition for prepreg of the present invention and the reinforcing fiber, compared with the fiber reinforced composite material obtained by using the conventional resin composition for prepreg, mechanical properties and resistance. Excellent corrosiveness.

Claims (1)

[Claims] 1. A resin obtained by adding acrylic acid and / or methacrylic acid to an epoxy resin, and (B)
A prepreg resin composition containing a peroxide as an essential component.