JPS634563B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a resin composition suitable for an unsaturated epoxy ester resin molding material having good heat and pressure moldability, and more specifically, to an unsaturated epoxy ester resin having free epoxy groups, an amino compound, and a polymerization initiator. It relates to a resin composition containing it as an essential component. Unsaturated epoxy ester resin (hereinafter referred to as epoxy acrylate resin) is a resin obtained by reacting an epoxy resin with acrylic acid or methacrylic acid, and has excellent corrosion resistance, so it is used in various corrosion-resistant devices, Used for corrosion-resistant linings, etc. Furthermore, due to its excellent mechanical properties and fatigue properties, it has recently been used as a structural resin for automobile parts and the like. In this way, epoxy acrylate resin is used for various purposes by taking advantage of its properties, but these mainly involve direct epoxy acrylate resin in the liquid resin state, such as hand lay-up, spray-up, and filament winding methods. In most cases, it is used in a molding process. On the other hand, recently, attempts have been made to manufacture and mold epoxy acrylate resin prepregs in order to improve productivity and work environment. Regarding the production of prepreg using epoxy acrylate resin, a method using a resin composition in which polyisocyanate is blended with epoxy acrylate resin,
A known method is to use a resin composition in which an acid anhydride (for example, maleic anhydride) is added to an epoxy acrylate resin to introduce an acid group, and magnesium oxide is blended into the resin. In the method using polyisocyanate, moisture or carboxyl groups remaining in the resin cause foaming during prepreg production and voids are generated in the prepreg, making it difficult to produce a good prepreg. In order to avoid this kind of phenomenon, the acid value of the epoxy acrylate resin must be reduced as much as possible to make it a low-acid-value resin, and furthermore, it is necessary to remove as much water as possible, which is a complicated process. The prepreg obtained in this manner has poor flow during hot-pressure molding, and is also difficult in terms of molding processing. In addition, in the method of introducing acid groups into epoxy acrylate resin and using magnesium oxide, it is extremely susceptible to the influence of moisture during prepreg production, and even moisture in the air can significantly affect the rate of viscosity increase. Sufficient water absorption control is required, and when molding using heat and pressure, the flow of the resin is too good, causing an imbalance in the amount of resin attached to the glass fibers, making it difficult to obtain uniform molded products. be. Furthermore, this method uses a resin with a high acid value as the epoxy acrylate resin and a strong basic compound such as magnesium oxide, which significantly reduces the corrosion resistance of the molded product and impairs the excellent properties of the epoxy acrylate resin. There are some disadvantages. In order to eliminate the various drawbacks described above, the present inventors have conducted repeated research on epoxy acrylate resin molding materials (prepreg), and as a result, they have used a resin having free epoxy groups as the epoxy acrylate resin, and added an amino compound to this resin. and a resin composition containing a polymerization initiator as an essential component,
It has been found that by impregnating or applying this onto a base material and aging it, an excellent molding material (prepreg) suitable for heat and pressure molding that eliminates the above-mentioned drawbacks can be obtained. That is, the present invention reduces free epoxy groups to 1×10 ^-5
The present invention relates to a resin composition containing as essential components an unsaturated epoxy ester resin having an equivalent/g to 2.4×10 ^-3 equivalent/g, an amino compound having at least two or more active hydrogen atoms in one molecule, and a polymerization initiator. The resin composition of the present invention generally maintains a viscosity suitable for manufacturing prepreg for 5 to 6 hours without causing a sudden change in viscosity at room temperature, and generally maintains a viscosity suitable for manufacturing prepreg for several hours by aging at a temperature of about 40°C. loses its fluidity in 3 to 4 hours, and the surface becomes non-sticky after about 1 day. In addition, it is not affected by moisture during prepreg production,
Good prepreg can be manufactured. As described above, the resin composition of the present invention is a resin composition containing as essential components an epoxy acrylate resin having a free epoxy group, an amino compound having at least two or more active hydrogen atoms in one molecule, and a polymerization initiator. It is. In the resin composition, the above-mentioned amino compound is used in an amount of 1 to 10 times, preferably 2 equivalents, based on the total oxirane oxygen of the free epoxy group.
The polymerization initiator is blended in a range of 6 to 6 times the equivalent amount, and the polymerization initiator is the above-mentioned free epoxy group-containing epoxy acrylate resin.
It is blended in a range of 0.1 to 5.0 parts by weight per 100 parts by weight. 1×10 ⁻⁵ equivalent/g in the resin composition of the present invention
Epoxy acrylate resins containing 2.4 x 10 ^-3 equivalents/g of free epoxy groups are prepared by combining the epoxy resin with acrylic acid or methacrylic acid, or replacing a portion of these unsaturated acids with a saturated acid, such as phthalic anhydride, tetrahydrocarbon It is obtained by reacting an acid component substituted with phthalic anhydride, isophthalic acid, maleic acid, maleic anhydride, fumaric acid, citraconic acid, etc. at a ratio of 0.5 to 1 equivalent of the acid component to the oxirane oxygen in the epoxy resin. It will be done.
In addition, the epoxy acrylate resin in the present invention also includes a resin obtained by further blending an appropriate epoxy resin with the above reaction product. Incidentally, when synthesizing the above-mentioned epoxy acrylate resin, an amine catalyst such as benzyldimethylamine is usually used. In addition, in order to facilitate the reaction during the synthesis of the epoxy acrylate resin, vinyl monomers that are added to the resin composition of the present invention, such as styrene and (meth)acrylic acid ester, and that can be polymerized during heat and pressure molding are added. It is preferable to synthesize it by The above-mentioned epoxy resins are those known per se, such as epichlorohydrin,
An average of 2 or more 2 in one molecule obtained by reacting an epihalohydrin such as methyl epichlorohydrin with a phenol compound such as bisphenol A, halogen-substituted bisphenol A, hydrogenated bisphenol A, bisphenol F, or phenol novolak. , 3-epoxypropyl group, and 2-methyl-2,3-epoxypropyl group, and a specific example is an epoxy resin commercially available from Ciel Chemical Co., Ltd. under the trade name Epicote. . The amino compound in the resin composition of the present invention is
A compound having at least two or more active hydrogens in one molecule, specifically polyalkylene polyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, bishexamethylenetriamine, diethylene glycol, bispropylamine, etc. polyether polyamine, dimethylaminopropylamine,
Aliphatic amines such as dialkylaminoalkylamines such as diethylaminopropylamine; aromatic nucleus-containing aliphatic amines such as benzylamine, xylylene diamine, etc.; 1,3-bisaminomethylcyclohexane, 1-amino-3-aminomethyl, Alicyclic amines such as 3,5,5-trimethylcyclohexane; 3,9-bis(3-aminopropyl)2,4,8,10-tetraoxa represented by N-aminoethylpiperazine, trade name Epomate; Amines containing a heterocycle such as spiro[5.5]undecane; and polyamides obtained by reacting the above-mentioned amines with polybasic acids. The polybasic acids mentioned here include, for example, dimers of monobasic acids obtained by the Diels-Alder reaction of dehydrated castor oil fatty acids, aromatic dibasic acids represented by phthalic acid, isophthalic acid, pyromellitic anhydride, etc. , aliphatic dibasic acids represented by adipic acid, succinic acid, etc., and unsaturated dibasic acids represented by fumaric acid, citraconic acid, itaconic acid, etc. As the polymerization initiator in the resin composition of the present invention, an organic peroxide is used which allows the resin composition to have a pot life of one day or more without gelation at a temperature of about room temperature even in the presence of an amino compound. Ru. Such organic peroxides are, for example,
Hydroperoxides such as quine hydroperoxide, dialkyl peroxides such as di-tertiary butyl peroxide, peroxy esters such as tertiary-butyl peroxybenzoate, 1,1-bis-tertiary butyl peroxy-3,3,5 -Alkylidene peroxides such as trimethylcyclohexane are exemplified. A polymerizable vinyl monomer, a thermoplastic resin, a filler, a reinforcing agent, a mold release agent, a coloring agent, etc. can be added to the resin composition of the present invention as desired. This polymerizable vinyl monomer is a monomer that can copolymerize the epoxy acrylate resin with the organic peracid, such as acrylic ester, methacrylic ester, styrene, vinyltoluene, α-methylstyrene, chlorostyrene, divinylbenzene, acetic acid. Vinyl, etc. are exemplified, and these are used singly or as a mixture of two or more. Thermoplastic resins are mainly used to suppress the shrinkage of molded products, such as:
Polymers or copolymers of styrene, acrylic esters, methacrylic esters, vinyltoluene, chlorostyrene, vinyl acetate, ethylene, propylene, butadiene, vinyl chloride, and these monomers with maleic anhydride, itaconic acid, acrylic acid, Examples include copolymers with unsaturated acids such as methacrylic acid. The amount of this thermoplastic resin to be added is determined depending on the purpose, but is generally about 5 to 15 parts by weight. As the filler, powders such as calcium carbonate, mica, and silica sand are used. As reinforcing agents, organic fibers such as vinylon and polyester, short fibers such as glass fibers, carbon fibers, boron fibers, metal fibers such as stainless steel, rovings, roving cloths, and mats are used. As the mold release agent, those generally used in sheet molding compounds and bulk molding compounds can be used. For example, higher fatty acids such as stearic acid and higher fatty acid metal salts such as zinc stearate are used. The resin composition of the present invention is blended with a filler, etc. as desired, and applied or impregnated onto a reinforcing agent (substrate) such as glass woven fabric or glass mat, and then heated to a predetermined temperature after defoaming according to a conventional method. By aging with
A prepreg that does not lose its fluidity within a few hours and that is easy to handle and has a semi-cured surface with no tackiness after several hours to more than ten hours is obtained. The obtained prepreg hardly changes even if it is left at room temperature for one month. Furthermore, this prepreg exhibits appropriate fluidity during hot-pressure molding, and the molded product is excellent without any loss in the inherent properties of the epoxy acrylate resin, such as corrosion resistance. Next, examples of the present invention will be shown. Example 1 (A) Synthesis of epoxy acrylate resin A bisphenol epoxy resin (Epicote #836 Ciel Chemical) with an epoxy equivalent of 300 was placed in a three-necked flask equipped with a stirrer, a reflux condenser, and a thermometer.
Add 900g of methacrylic acid, 206g of methacrylic acid, 596g of styrene monomer, 3.4g of dimethylbenzylamine, and 0.85g of hydroquinone and react at 120°C for 2 hours and 30 minutes with stirring. After cooling to room temperature, add bisphenol having an epoxy equivalent of 300. 90 g of epoxy resin (Epicoat #836 Ciel Chemical) was added and mixed well to obtain an epoxy acrylate resin having an acid value of 3.0 and an epoxy group content of 5.01×10 ⁻⁴ equivalent/g. To 100 parts by weight of the resin, 1 part by weight of tert-butyl perbenzoate as a polymerization initiator, 15 parts by weight of polyamide (trade name: Tomide 225, manufactured by Fuji Kasei Co., Ltd.) and 2 parts by weight of zinc stearate were added and mixed well. A resin composition having a viscosity of 50 poise at 25°C was obtained (referred to as resin composition (A-1)). The resin composition had a viscosity of 55 poise after being left at 25°C for 2 hours. (B) Evaluation of resin A #450 glass mat was impregnated with the resin composition (A-1), both sides were covered with polyethylene film, and after defoaming, it was wound up into a roll and aged in a thermostatic chamber at 50°C. Ta. After 2 hours, the fluidity disappeared, and after 18 hours, a prepreg (B-1) having a glass content of 30% and showing no surface tackiness at room temperature was obtained.
The prepreg (B-1) was pressure-molded at 150° C. for 3 minutes to obtain a molded product, which was then subjected to a corrosion resistance test. Corrosion resistance and physical properties are shown in Table 1. Comparative Example 1 (A) Synthesis of epoxy acrylate resin A bisphenol epoxy resin (Epicoat #836
Ciel Chemical) 900g, methacrylic acid 258g,
Add 623 g of styrene monomer, 3.6 g of dimethylbenzylamine, and 1.25 g of hydroquinone, and react with stirring at 130°C for 4 hours and 30 minutes, with an acid value of 4.0.
An epoxy acrylate resin was obtained. The resin 100
To parts by weight, 1 part by weight of tert-butyl perbenzoate as a polymerization initiator, polyisocyanate A resin composition was obtained by mixing 18 parts by weight of a glycol-modified product of MDI (represented by the following formula) and 2 parts by weight of zinc stearate (referred to as resin composition (A-2)). A #450 glass mat was impregnated with the resin composition (A-2), both sides of which were covered with polyethylene film, defoamed, and then wound into a roll. When aged at 20°C, the resin flowed out due to foaming after 1 hour, making it impossible to produce a good prepreg. Comparative Example 2 (A) Synthesis of epoxy acrylate resin A bisphenol epoxy resin (Epicoat #836
Ciel Chemical) 900g, methacrylic acid 258g,
After adding 623 g of styrene monomer, 3.6 g of dimethylbenzylamine, and 1.25 g of hydroquinone and reacting at 130°C with stirring for 4 hours, the temperature was increased to 100°C.
After cooling to 100℃, add 250g of phthalic anhydride.
The mixture was allowed to react for 3 hours. The acid value of the obtained resin is 51mg
It was KOH/g. 100 parts by weight of the resin, 1 part by weight of tertiary butyl perbenzoate, and zinc stearate.
2 parts by weight and 2 parts by weight of MgO were added and mixed well to obtain a resin composition (referred to as resin composition (A-3)). (B) Evaluation of resin A #450 glass mat was impregnated with the above resin composition (A-3), both sides were covered with polyethylene film, and after defoaming, it was wound into a roll and kept in a constant temperature room at 40°C.
After aging for 48 hours, a prepreg (B-2) with a glass content of 30% was obtained. This prepreg (B-2) was molded under the same conditions as in Example 1 to obtain a molded product, and the corrosion resistance and physical properties of the molded product were examined. The results are shown in Table 1.

[Table] Example 2 (A) Production of epoxy acrylate resin A bisphenol-based epoxy resin with an epoxy equivalent of 187 (Epicoat #828
Ciel Chemical) 1122g, acrylic acid 302g,
2.8 g of dimethylbenzylamine and 0.71 g of hydroquinone were added and reacted at 120° C. for 2 hours with stirring to obtain an epoxy acrylate resin with an acid value of 5.0 and an epoxy group content of 1.26×10 ⁻³ equivalent/g. To 100 parts by weight of the resin, 1 part by weight of bis(4-tert-butylcyclohexyl) peroxydicarbonate and 25 parts by weight of polyamide (Thomide 225, similar to that used in Example 1) were added, mixed well, and heated at room temperature (25°C). ) to obtain a resin composition (A-2) with a viscosity of 250 poise. (B) Evaluation of resin A glass mat similar to that used in Example 1 was impregnated with the resin composition (A-2), both sides were covered with polyethylene film, and after defoaming, the resin composition (A-2) was soaked in a constant temperature room at 30°C for 24 hours.
After aging, a prepreg (B-3) with a glass content of 20% and a surface showing almost no tackiness was obtained.
Even when this prepreg was left at 20°C for one month, there was almost no change other than a slight hardening. This prepreg was sandwiched between sanded unsaturated polyester resin FRPs in an L shape, pressed together with a force of 0.5 kg/cm ² , and cured at 70° C. for 30 minutes. As a result of measuring the adhesive strength of the cured product, all of the 10 measurements resulted in material failure, but the parts bonded with prepreg did not break. Example 3 (A) Production of epoxy acrylate resin A bisphenol epoxy resin (Epicoat #1001 with an epoxy equivalent of 450) was placed in the same equipment as in Example 1.
After adding 900 g of methacrylic acid, 155 g of methacrylic acid, 703 g of styrene monomer, 3.6 g of dimethylbenzylamine, and 0.88 g of hydroquinone and reacting at 125°C for 3 hours and 20 minutes with stirring, the mixture was cooled to room temperature. Add 120g of phenol-based epoxy resin (Epicote #828 Ciel Chemical), acid value 7.0, epoxy group content
An epoxy acrylate resin of 4.5×10 ⁻⁴ equivalent/g was obtained. To 100 parts by weight of the resin, 150 parts by weight of mica powder,
Add 3 parts by weight of zinc stearate, 1.5 parts by weight of tert-butyl perbenzoate, 30 parts by weight of polystyrene (30% styrene solution) and 3 parts by weight of triethylenetetramine and mix well to obtain a resin with a viscosity of 35 poise at room temperature (25°C). Composition (A-3)
was prepared. (B) Evaluation of resin After impregnating the resin composition (A-3) into a glass mat similar to that used in Example 1, both sides were covered with polyethylene film and after degassing, the resin composition (A-3) was kept in a constant temperature room at 70°C for 3 hours. A sheet molding compound (B-4) having a glass content of 15% and having no surface tackiness at room temperature was obtained by aging. 150% of this sheet molding compound
The cured product that was pressure molded for 3 minutes at 100°C was placed in water at 100°C for 3 minutes.
No change in appearance was observed even after soaking for several months. Example 4 (A) Production of epoxy acrylate resin Into the same apparatus as in Example 1, 900 g of novolak epoxy resin (Epicote #154 Ciel Chemical) with an epoxy equivalent of 180, methacrylic acid, 323 g, styrene monomer 524 g, and dimethylbenzylamine were added.
Add 3.5g and 1.0g of hydroquinone and react at 120℃ for 2 hours, acid value 11.0, epoxy group content 7.2
An epoxy acrylate resin of x10 ^-4 equivalent/g was obtained. To 100 parts by weight of the resin, 2 parts by weight of zinc stearate, 1,1-bis(tert-butylperoxy)3,3,5-trimethylcyclohexane
1 part by weight and 5 parts by weight of metaxylylene diamine were added and mixed well to form a viscous resin composition (A-
5) was obtained. This resin composition exhibits only a slight change in viscosity even after being left at room temperature for 8 hours, and is suitable as a resin composition for prepregs. (B) Evaluation of resin The resin composition (A-5) was impregnated into #800 pin cloth, both sides were covered with polyethylene film, and after defoaming, it was wound up into a roll and left in a constant temperature room at 50°C for 6 hours. Glass content without surface stickiness at room temperature
A 50% prepreg (B-5) was obtained. The cured product obtained by pressure molding this prepreg at 130℃ for 5 minutes has a heat distortion temperature of 150℃ and a tensile strength of
It was 25.0Kg/ ^mm2 . Example 5 (A) Production of epoxy acrylate resin A bisphenol epoxy resin with an epoxy equivalent of 187 (Epicoat #838
Ciel Chemical) 561g, methacrylic acid 344g, adipic acid 146g, styrene monomer 827g, dimethylbenzylamine 3g and hydroquinone
Add 0.75g of epoxy and react with stirring at 120℃ for 2 hours, cool to room temperature, and add epoxy equivalent
Add 187g of biphenol-based epoxy resin (Epicote #828 Ciel Chemical) and mix well to obtain an acid value of 7.5 and an epoxy group content of 6.2×10 ^-4 equivalent/
g of epoxy acrylate resin was obtained. The resin
100 parts by weight, 1,1-bis(tert-butylperoxy)-3,3,5 as a polymerization initiator
- Trimethylcyclohexane 1 part by weight, polyamide [trade name Tomide 225, Fuji Kasei Co., Ltd.] 20
parts by weight and 2 parts by weight of zinc stearate,
After thorough mixing, a resin composition (A-6) having a viscosity of 65 poise at 25°C was obtained. (B) Wet value of resin After impregnating the resin composition (A-6) into a glass mat similar to that used in Example 1, both sides were covered with polyethylene film, defoamed, and rolled into a roll. Rolled up and aged in a constant temperature room at 50℃ for 12 hours, glass content 25% slightly sticky at room temperature
prepreg was obtained. The cured product formed by pressurizing this prepreg at 130℃ for 4 minutes has a tensile modulus of elasticity of
The weight was 210Kg/mm ² and the tensile elongation was 6.8%.

Claims (1)

[Scope of Claims] 1. A reaction product obtained by reacting an epoxy resin with acrylic acid or methacrylic acid, or a composition in which an epoxy resin is blended with the reaction product, wherein the free epoxy group is 1×10 ^{- 5} equivalents/g to 2.4×10 ^-3 equivalents/g selected from the group consisting of unsaturated epoxy ester resins, aliphatic amines, alicyclic amines, amines containing heterocycles, aliphatic amines containing aromatic nuclei, and polyamides. at least one kind of amino compound and hydroperoxide having at least two active hydrogens in one molecule;
A resin composition containing as an essential component at least one polymerization initiator selected from the group consisting of dialkyl peroxide, peroxy ester, and alkylidene peroxide. 2. The resin composition according to claim 1, wherein a reaction product obtained by reacting an acid component in which a part of acrylic acid or methacrylic acid is replaced with a saturated acid with an epoxy resin is used as the unsaturated epoxy ester resin. 3. The resin composition according to claim 1, wherein the amino compound is contained in an amount of 1 to 10 times equivalent to the total oxirane oxygen of free epoxy groups in the unsaturated epoxy ester resin. 4. The resin composition according to claim 1, which contains the polymerization initiator in a proportion of 0.1 to 5 parts by weight based on 100 parts by weight of the unsaturated epoxy ester resin.