JPH07691B2 - Resin composition for molding material - Google Patents

Description

TECHNICAL FIELD The present invention relates to an unsaturated polyester resin for a molding material for producing an FRP molded article.

The resin composition of the present invention, for example, an SMC or BMC molding material obtained by impregnating a fiber reinforcing material such as glass fiber has excellent thickening properties, excellent impact resistance, and obtains a FRP molded product having a beautiful surface. be able to.

[Prior Art] As a means for imparting viscosity to a molding material, for example, a method using an oxide of an alkaline earth metal such as magnesium oxide or a method using a polyisocyanate compound such as MDI is known. Of these, when a polyisocyanate compound is used as a thickener, compared to the case where an oxide of an alkaline earth metal is used as a thickener, the viscosity is excellent during SMC production and the chemical resistance of the molded product is also excellent. It is said to be good. However, when such a polyisocyanate compound is used as a thickener, there is a drawback that foaming occurs in a molding material obtained from a resin composition in which glass fibers are impregnated with a normal unsaturated polyester, It is said that an FRP molded article made of such a molding material generally has an unsatisfactory surface, and a product having sufficient mechanical strength cannot be obtained.

[Problems to be Solved by the Invention] The present invention is a polyisocyanate-based molding material, which suppresses foaming during polyisocyanate mixing, has a beautiful surface, and has excellent mechanical strength, particularly impact resistance It is intended to provide a composition.

[Means for Solving the Problems]

The present inventors dilute the reaction product obtained by reacting the unsaturated polyester with a glycidyl compound of a saturated fatty acid or a saturated alcohol with an unsaturated monomer such as styrene,
A resin composition obtained by impregnating this with a polyisocyanate compound such as MDI together with other compounding agents into a fiber reinforcing material,
Compared with ordinary unsaturated polyester resin, it has excellent viscosity increase, that is, the amount of polyisocyanate compound required for viscosity increase is small, and it has the effect of suppressing foaming during viscosity increase, and the obtained molding material is excellent in the mold. It has excellent fluidity, does not have the yellowish brown spots and pinholes seen on molded products, and has excellent mechanical properties, especially impact resistance, of the FRP product itself obtained from such molded materials. I found that. The present invention has been made based on these findings.

That is, the present invention is a resin composition for a molding material comprising (a) a reaction product of an unsaturated polyester and a glycidyl compound of a saturated fatty acid or a saturated alcohol, (b) an unsaturated monomer and (c) a polyisocyanate compound. .

First, the component (a) in the present invention will be described.

The unsaturated polyester used as the raw material of the component (a) is obtained by reacting an α, β-unsaturated dibasic acid or its anhydride with glycols by a conventional method, and has a molecular weight of 1,000 to 4,000, preferably 1,500 to 2,5
00. 15 to 50 mg of these unsaturated polyesters
It has an acid value of KOH / g. Examples of the α, β-unsaturated dibasic acid or anhydride thereof include unsaturated dicarboxylic acids such as maleic acid, fumaric acid and maleic anhydride, and anhydrides thereof, and glycols include, for example, ethylene. Glycol, propylene glycol, butanediol, neopentyl glycol,
1,6 hexanediol, diethylene glycol, dipropylene glycol, hydrogenated bisphenol A, 2,2 '
-Di (4-hydroxypropoxyphenyl) propane,
Mention may be made of diols such as 2,2'-di (4-hydroxyethoxyphenyl) propane. In addition to these components, if necessary, a saturated dicarboxylic acid such as orthophthalic acid, an anhydride thereof, isophthalic acid, terephthalic acid, adipic acid, succinic acid, tetrachlorophthalic anhydride, or hettic acid can be appropriately used. .

As the glycidyl compound of a saturated fatty acid or a saturated alcohol which is another raw material for producing the component (a), a saturated fatty acid or a glycidyl compound of a saturated alcohol having 2 to 18 carbon atoms, preferably 4 to 12 carbon atoms is suitable. Specific examples thereof include versatic acid glycidyl ester, n-butyl glycidyl ether, and 2-ethylhexyl glycidyl ether. If the carbon number exceeds 18, the mechanical strength of the FRP molded product tends to decrease.

The acid value of the reaction product can be adjusted by increasing or decreasing the amount of the glycidyl compound of the saturated fatty acid or the saturated alcohol. Other glycidyl compounds such as phenyl glycidyl ether and glycidyl methacrylate can also be used as raw materials, but FRP from a molding material obtained using a resin composition using phenyl glycidyl ether
Molded products have the drawbacks that their mechanical strength, particularly impact resistance, is insufficient, and that the molding material obtained using a resin composition containing glycidyl methacrylate has poor storage stability.

In order to obtain the component (a) by reacting the above-mentioned two raw materials, the unsaturated polyester is almost
The reaction is performed while gradually adding 0.8 to 1.5 epoxy equivalents of a glycidyl compound of a saturated fatty acid or a saturated alcohol. This reaction is carried out at about 70 to 130 ° C., and organic amines such as triethylamine, and salts of basic metals such as lithium chloride are usually used as a reaction catalyst. Further, polyhydric phenols such as hydroquinone may be added as a polymerization inhibitor. Reaction is usually 30 minutes ~
It will be finished in about 3 hours. The reaction product (a) thus obtained usually has an acid value of 3 mgKOH / g or less, and an unsaturated polyester resin can be obtained by diluting it with the component (b) as it is.

The component (b) used in the present invention is a monomer copolymerizable with the above component (a).
For example, styrene, vinyltoluene, chlorostyrene,
Examples thereof include divinylbenzene, diallyl phthalate, triallyl cyanurate, acrylic acid ester, and methacrylic acid ester. The component (b) is blended in such a proportion that it accounts for approximately 20 to 60% by weight of the total amount of the component (a).

Examples of the component (c) used in the present invention include hexamethylene diisocyanate, tetramethylene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, 4,4 ′ -Diphenylmethane diisocyanate, diisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and naphthalene diisocyanate, polyfunctional isocyanates such as polymethylene polyphenyl isocyanate, and terminal hydroxyls of polyester polyols or polyether polyols. Molecular weight of 500- with isocyanate group added to the end by reacting the group with a diisocyanate compound
5,000 isocyanate prepolymers can be mentioned. In the component (c), the number of amine equivalents of the component (c) is about 0.
The amount is 2 to 1.2, preferably 0.4 to 0.8.

The resin composition of the present invention can be obtained by mixing the above components (a), (b) and (c). The resin composition of the present invention can contain various compounding materials commonly used for molding materials such as SMC and BMC. Examples of such compounding agents include inorganic fillers such as calcium carbonate, aluminum hydroxide and barium sulfate, organic peroxides such as methyl ethyl ketone peroxide and t-butyl-peroxybenzoate, such as polyethylene, polystyrene and polyvinyl acetate. , Thermoplastic resins such as polymethylmethacrylate, internal release agents such as calcium stearate and zinc stearate, urethanization catalysts such as dibutyltin dilaurate, dibutyltin diacetate and stannas octoate, and toners. Can be mentioned.

A conventional method can be used for producing a molding material such as SMC or BMC from the resin composition of the present invention. For example
The SMC can be produced by adding the component (c) to a resin mixture obtained by mixing the component (a), the component (b) and various conventional compounding materials and impregnating the glass fiber.

〔Example〕

Hereinafter, for better understanding of the method for carrying out the present invention,
The following examples are presented for purposes of illustration and not limitation. However, all parts are parts by weight.

Reference Example 1 Production of Unsaturated Polyester Resin (A) Isophthalic acid 415 parts, propylene glycol 837 parts, and hydroquinone 0.21 parts were reacted at 190 ° C., and when the acid value of the reaction product reached 10 mgKOH / g, fumaric acid 871 was further added. Parts,
The reaction was continued at 210 ° C. The reaction was terminated when the acid value reached 30 mgKOH / g to obtain an unsaturated polyester. This unsaturated polyester is cooled to 100 ° C and triethylamine 2
After the addition of 211 parts, 211 parts of versatic acid glycidyl ester (Cajura E10 made by Shell Chemical Co., Ltd.) was gradually added dropwise, and the reaction was continued at 100 ° C. for 60 minutes until the acid value reached 2.6 mg KOH / g.
Hydroquinone (0.21 part) and styrene (1175) were added to the reaction product.
A styrene solution dissolved in 1 part was added to obtain an unsaturated polyester resin (A).

Production of unsaturated polyester resin (A ') Isophthalic acid 415 parts, propylene glycol 837 parts, hydroquinone 0.21 parts were reacted at 190 ° C, and when the acid value of the reaction product reached 10 mgKOH / g, fumaric acid 871 parts was further added. In addition,
The reaction was continued at 210 ° C. When the acid value reached 30 mgKOH / g, the reaction was terminated and a styrene solution prepared by dissolving 0.21 part of hydroquinone in 1175 parts of styrene was added to obtain an unsaturated polyester resin (A ').

Manufacture of unsaturated polyester resin (B) Neopentyl glycol 492 parts, propylene glycol 4
40 parts, 1161 parts fumaric acid, 0.20 parts hydroquinone at 200 ° C
And the reaction was terminated when the acid value of the reaction product reached 42 mgKOH / g to obtain an unsaturated polyester. This unsaturated polyester was cooled to 100 ° C., 2 parts of triethylamine was added thereto, and then 161 parts of n-butylglycidyl ester (Kurdura E10 manufactured by Shell Chemical Co., Ltd.) was gradually added dropwise until the acid value reached 2.5 mgKOH / g. The reaction was continued at 100 ° C for 50 minutes. 0.21 parts of hydroquinone was added to styrene in this reaction product.
A styrene solution dissolved in 1155 parts was added to obtain an unsaturated polyester (B).

Manufacture of unsaturated polyester (B ') Neopentyl glycol 492 parts, propylene glycol 4
40 parts, 1161 parts fumaric acid, 0.20 parts hydroquinone at 200 ° C
The reaction was terminated when the acid value of the reaction product reached 40 mgKOH / g and 0.20 parts of hydroquinone was added to styrene 1155
An unsaturated polyester (B ') was obtained by adding a styrene solution dissolved in the above parts.

Examples 1 and 2 and Comparative Examples 1 and 2 The resin compositions of the present invention shown in Table 1 were mixed and impregnated into glass fibers to produce SMC. After leaving this SMC at room temperature for 24 hours, after peeling off the polyethylene sheet and confirming that there is no adhesiveness, after checking the foaming state of SMC, this is heated and compression molded with a mold, and FRP molding A plate was manufactured, and the presence or absence of pinholes on the surface and the presence or absence of discoloration were observed to measure the mechanical strength (in accordance with JIS K6911). The obtained results are shown in Table 2.

From the results shown in Table 2, the SMCs produced from the resin compositions of Examples 1 and 2 of the present invention had no foaming and the FRP molded plate obtained by warm compression molding had no pinholes or discoloration, and had no mechanical properties. It was found that the physical properties, especially the impact resistance, were excellent.

Examples 3 and 4 and Comparative Examples 3 and 4 The resin compositions of the present invention shown in Table 3 were mixed and impregnated into glass fibers to produce high-strength SMCs. The SMCs were left at room temperature for 24 hours, and then the polyethylenes After peeling the sheet and confirming that there is no adhesiveness, check the foaming state of SMC, heat and compression mold this with a mold to manufacture an FRP molded plate, and check for pinholes on the surface and for discoloration. It was observed and the mechanical strength was measured (in accordance with JIS K6911). The results obtained are shown in Table 4.

From the results shown in Table 4, the high-strength SMCs produced from the resin compositions of Examples 3 and 4 of the present invention had no foaming, and the FRP molded plate obtained by warm compression molding had no discoloration and mechanical properties. ,
In particular, it was recognized that the impact resistance was excellent.

〔The invention's effect〕

The resin composition of the present invention has excellent thickening properties, and the FRP molded products derived from BMC and SMC of the present invention have a beautiful molded product surface and excellent mechanical properties, particularly impact resistance. . Therefore, it is useful as an automobile part such as an underbody panel, engine hood, and bumper.

Claims (1)

[Claims] 1. A resin composition for a molding material comprising (a) a reaction product of an unsaturated polyester and a glycidyl compound of a saturated fatty acid or a saturated alcohol, (b) an unsaturated monomer and (c) a polyisocyanate compound.