JPH02274737A - Production of molding and resin composition for polystyrene foam - Google Patents

Abstract

PURPOSE:To produce a molding which is insoluble in an unsaturated polyester and can be used as a core material or a base of a stiffener structure or a sandwich structure by coating a polystyrene foam with a resin containing an unsaturated ester obtained by reacting an epoxy resin with an unsaturated monobasic acid and a specified acrylic compound and curing the applied resin. CONSTITUTION:A molding is obtained by coating a polystyrene foam with a resin composition comprising 100 pts.wt. unsaturated ester obtained by reacting an epoxy resin with an unsaturated monobasic acid such as methacrylic acid and 5 to 150 pts.wt. hydroxyalkyl (meth)acrylate of formula I (wherein R<1> is H or CH3; and R<2> is a 2 to 12C alkylene or oxyalkylene) [e.g. dicyclopentenyloxyethyl (meth)acrylate] and 5 to 150 pts.wt. hydroxyalkyl (meth) acrylate of formula II (wherein R<1> and R<2> are as defined in formula I), and the applied composition is cured to obtain a molding.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for producing a molded article and a resin composition for polystyrene foam, and more specifically to a method for producing a molded article using polystyrene foam as a core or base material. The present invention relates to a resin composition for polystyrene foam.

[Conventional technology]

Unsaturated polyester resin is obtained by dissolving unsaturated polyester in styrene, etc., and the cured product has electrical properties,
Because it has well-balanced mechanical properties, thermal properties, workability, price, etc., it is used for many purposes such as FRP, casting, and painting.

In particular, FRP using unsaturated polynisder resin has excellent specific strength and is widely used as an alternative structural member to metal in fields such as fishing boats, boats, septic tanks, tanks, silos, automobiles, and aircraft. Since this is low, efforts have been made to increase the rigidity of structural members by adopting a stiffener structure or a sand inch structure. Currently, hard urethane foam is mainly used as the core material for the stiffener structure or the sandwich structure, but it has the disadvantage of poor workability.

On the other hand, there is polystyrene foam as a lightweight foam, which can be energized and easily cut with a red-hot nichrome wire, and can be easily shaved with a file, so it can be processed into complex shapes with high precision. is possible. However, when conventional unsaturated polyester resin is applied to this polystyrene foam as a core material or base material for a stiffener structure or a sandwich structure, the polystyrene foam dissolves, making it impossible to produce a molded product.

[Problem to be solved by the invention]

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide a method for manufacturing a molded article in which polystyrene foam can be used as a core material or base material, and a resin composition for polystyrene foam.

[Means to solve the problem]

The first aspect of the present invention is (a) 100 parts by weight of an unsaturated ester obtained by reacting an epoxy resin with an unsaturated basic acid;
b) - Formula (1) (wherein R1 is a hydrogen atom or a methyl group, R2 is an alkylene group of 2 to 12 carbon atoms or 4 to 12 carbon atoms and a group that connects distant segments of the alkylene group) 5 to 150 parts by weight of a compound having at least one oxygen atom (meaning an oxalkylene group in which this segment has at least two carbon atoms) and (C)-formula (II) Hz C=C-C-R2--OHCJ) (wherein, R1
and R2 are the same as in general formula (1)) Compound 5
The present invention relates to a method for producing a molded article, in which a resin composition containing 150 parts by weight is coated on polystyrene foam and cured.

In addition, the second aspect of the present invention includes 100 parts by weight of the unsaturated ester obtained by reacting the epoxy resin with the unsaturated basic acid (a), and the compound 5 to 1 of the compound represented by the formula (I) (b).
The present invention relates to a resin composition for polystyrene foam comprising 50 parts by weight and 5 to 150 parts by weight of the compound represented by (C)-formula (■).

There are no particular restrictions on the epoxy resin used in the present invention,
For example, one represented by the following formula (wherein X means an integer in the range of 0 to 15) is used. These commercially available products include Epikot 828 and Epicoat 10 manufactured by Shell Chemical Co., Ltd.
01, Epicote 1004, etc., product name A manufactured by Asahi Kasei Industries, Ltd.
ER-661H, AER331, AER-337, etc., product names manufactured by Dow Chemical Company, E, R, 300, D, 1E,
There are R, 660, D, E, R, 664, etc.

It is also possible to use an epoxy resin in which some of the hydrogen atoms are replaced with halogens such as bromine. These commercially available products include Meiko Bototo YDB manufactured by Tobu Kasei Co., Ltd.
-400 and YDB-340 epoxy resins can be used alone or in combination of two or more.

Unsaturated to be reacted with the epoxy resin used in the present invention
As basic acids, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, tricyclo(5,2°1.0"6]-4-
Partially esterified carboxylic acids containing decene-8 or 9 residues and unsaturated dibasic acid residues as constituent elements can be used. Examples of this partially esterified carboxylic acid include 8- or 9-hydroxytricyclodecene-4-(
5゜2, 1. 02・') 1.00 to 1.20 mol and 1 mol of an unsaturated dibasic acid such as maleic anhydride, itaconic acid, citraconic acid, etc. to 70 to 15 mol under an inert gas stream.
Unsaturated dibasic acid monoester obtained by heating at 0°C, tricyclodecadiene-4,8-(5°2.1.02
There are unsaturated dibasic acid monoesters obtained by adding unsaturated dibasic acids such as maleic acid, fumaric acid, and itaconic acid to 6] in the presence of a catalyst such as sulfuric acid and Lewis acid.

Tricyclodecadiene-48-[5,2,1°, etc.

Further - formula (III) -t (wherein R,, R2 and R3 are hydrogen atoms or alkyl groups, which may be the same or different,
X is an integer in the range of 0 to 15) can also be used. These commercially available products include the product name E manufactured by Dow Chemical Company.

N, 431, D, E, N, 438, etc., trade name Pico-1-152, Epicoat 154, manufactured by Shell Chemical Co., Ltd., and EPN1138, manufactured by Chiha Corporation.

Also, Union Carbide's product name ERL4221, Ciba Geigy's product names CY208, cy221, CY3
50, XB2615, CY192, CY184, etc. can also be used.

The reaction between 02゛6:l and maleic acid is represented by the following formula.

The unsaturated ester in the present invention is obtained by heating the epoxy resin and the unsaturated basic acid to 60 to 150°C, preferably 70 to 130°C, and reacting them. At this time, the amount of carboxyl groups is determined, and the acid value of the unsaturated ester obtained is preferably 50 or less, more preferably 15 or less.

A polybasic acid is used in the reaction as necessary. Examples of the polybasic acids include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, adipic acid, acelaic acid, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, and trimellitic anhydride. Examples include.

The proportion of the unsaturated basic acid and the polybasic acid used as necessary is preferably such that the carboxyl groups of these acid components and the epoxy groups of the epoxy resin are approximately equal in amount.

When reacting the unsaturated ester of the present invention, it is preferable to use a polymerization inhibitor such as hydroquinone, parahenzoquinone, p-tertiary butylcatechol, or hydroquinone monomethyl ether in order to prevent gelation due to polymerization. In addition, to shorten the reaction time, quaternary ammonium salts such as trimethylhensyl ammonium chloride and pyridinium chloride, tertiary amines such as triethylamine and dimethylaniline, ferric chloride, lithium hydroxide, lithium chloride, and ferric chloride. Esterification catalysts such as tin can be used.

The compound represented by the general formula (I) used in the present invention is a known compound, for example, in Japanese Patent Publication No. 61-43337.
It can be obtained by the manufacturing method shown in Japanese Patent Application Laid-Open No. 57-200331. In the former method, alkylene glycol monodicyclobentenyl ether or oxaalkylene glycol monodicyclobentenyl ether produced by addition reaction of alkylene glycol or oxaalkylene glycol to dicyclopentadiene is subjected to a condensation reaction with methacrylic acid. Alternatively, methyl methacrylate is obtained by transesterification, and in the latter method, alkylene glycol mono
(Meth)acrylate (indicates methacrylate or acrylate).

(below) is obtained by addition reaction with dicyclopentadiene.

Examples of the compound represented by the general formula (1) include dicyclopentenyloxyethyl (meth)acrylate and dicyclopentenyloxypropyl (meth)acrylate.

Compounds of general formula (If) used in the present invention include:
Examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxyethyloxyethyl (meth)acrylate.

The resin composition used in the present invention contains (b) - a compound represented by formula (1) and (C) - a compound represented by formula (■) based on 100 parts by weight of the unsaturated ester (a). It contains 5 to 150 parts by weight of each compound. If the amount of formula (I) and formula (If) used is less than 5 parts by weight, the viscosity of the resin composition will be too high, and if it exceeds 150 parts by weight, the hardness of the resin composition will be insufficient. In particular, if the amount of the compound represented by formula (■) exceeds 150 parts by weight, the water resistance of the cured product will deteriorate.

The method for manufacturing a molded article according to the present invention includes adding the resin composition to the resin composition.
This is done by adding an organic peroxide catalyst as a curing agent and a curing accelerator if necessary, applying it to polystyrene foam, and then curing at room temperature or under heating. Further, curing can also be performed by electron beam. As the organic peroxide catalyst, benzoyl peroxide, methyl ethyl ketone peroxide, tertiary butyl hydroperoxide, cumene hydroperoxide, dicumyl peroxide, etc. are used. Further, as the curing accelerator, metal soaps such as cobalt naphthenate and manganese naphthenate, amines such as lauryl mercaptan, β-diketones, dimethylaniline, and triethanolamine, and the like are used.

The polystyrene foam used in the present invention is obtained by foaming polystyrene to which a blowing agent and, if necessary, additives such as a flame retardant are added. The density LL' of the polystyrene foam is preferably in the range of 0.013 to 0.025 g/c+ff.

The general manufacturing method for polystyrene foam is to first foam the bead-shaped raw material by heating it in advance, then leave it for an appropriate period of time, cure it, dry it, and then process it to obtain a shape such as a plate or cylinder. There are two methods: filling it in a mold, reheating it to cause secondary foaming, and then fusing it, and heating and melting the raw material, continuously extruding it to foam it, and cutting it to obtain a plate shape. be. There are no particular limitations on the polystyrene frame used in the present invention.

To apply the resin composition onto the polystyrene foam, the same methods as for applying conventional paints can be used, such as spraying, brushing, flow coating, and dipping.

Further, in the present invention, the resin composition can be laminated on polystyrene foam together with various reinforcing materials and cured to form a molded product. As the reinforcing material, inorganic fibers or organic vA fibers such as glass fibers, carbon fibers, aramid fibers, polyester fibers, and rayon fibers are used, and the forms of these include woven fabrics, nonwoven fabrics, rovings, etc. Chopped strands are used. Alternatively, a fabric in which two or more of these types are woven simultaneously may be used. Furthermore, paper such as kraft paper can also be used.

The methods of laminating the resin composition together with various reinforcing materials on polystyrene foam are the same as those for normal FRP molding, such as the hand-rearing method, spray-up method, cold press method, filament winding method, back molding method, and Matsushi Tomekuru die method. A method can be used.

The resin composition of the present invention may also contain additives, such as antioxidants, accelerators, dyes, fillers, pigments, antistatic agents, flame retardants, thickeners, thixotropic agents, and surfactants. , a viscosity modifier, a plasticizer, a thermoplastic resin, etc. can be contained.

〔Example〕

Example 1 1) Synthesis of unsaturated ester 172 parts by weight of methacrylic acid, Ebibis type epoxy resin (trade name Epicoat 82 manufactured by Yuka Shell Epoxy Co., Ltd.)
8. Epoxy equivalent: 190) 380 parts by weight, 0.07 parts by weight of hydroquinone, and 7.0 parts by weight of trimethylbenzylammonium chloride were heated at 90°C for 8 hours to obtain an unsaturated ester with an acid value of 15.

2) Synthesis of dicyclopentenyloxyethyl acrylate 660 parts by weight of dicyclopentadiene, 160 parts by weight of ethylene glycol, and 4 parts by weight of para-toluenesulfonic acid were added to 1 part by weight.
After reacting at 20°C for 4 hours, the temperature was lowered to 80°C, 360 parts by weight of acrylic acid and 4 parts by weight of para-toluenesulfonic acid were added, and the reaction was carried out at 100°C for 5 hours while distilling water. The reaction product obtained was neutralized with magnesium oxide. After washing the reaction product with water, it was purified by vacuum distillation.

3) Preparation of resin composition The unsaturated ester and dicyclopentenyloxyethyl acrylate obtained above and 2-hydroxyethyl methacrylate were mixed and dissolved in the amounts shown in Table 1. Its properties are shown in Table 1.

4) Coating on polystyrene foam To 100 parts by weight of the obtained resin composition, 2.0 parts by weight of cobalt naphthenate (metal content: 6% by weight), 0.04 parts by weight of dimethylaniline, and 1.0 parts by weight of 55% by weight methyl ethyl ketone peroxide. Add 0 parts by weight and stir well to make a thickness of 2.
It was applied with a brush to a polystyrene foam shaped into 30 cm long and 30 cm wide. The polystyrene foam did not melt, and after 24 hours, a polystyrene foam coated with a non-sticky coating was obtained.

5) Lamination of FRP on polystyrene foam The same resin composition 10 as above was placed on the same polystyrene foam as above.
Using 0 parts by weight, two sheets of glass mats each weighing 450 g per 1M were laminated as reinforcing materials and allowed to stand at room temperature to harden. The polystyrene foam did not dissolve and an FRP layer was formed.

Comparative Example 1 The unsaturated ester obtained in 1) of Example 1 and styrene were mixed and dissolved in the proportions shown in Table 1, and the properties of the resulting resin composition are shown in Table 1. Further, when this resin composition was applied to polystyrene foam in the same manner as in Example 1, 4), the polystyrene foam instantly dissolved. Furthermore, using this resin composition, 5) of Example 1
I layered FRP on polystyrene foam in the same way as above, but the polystyrene foam melted instantly.
FRP could not be laminated.

Table 1 [Effects of the Invention] According to the present invention, it is possible to obtain a molded article using polystyrene foam as a core material or base material without dissolving polystyrene foam, having excellent workability, and having good dimensional accuracy.

■

Claims (1)

[Claims] 1. (a) 100 parts by weight of an unsaturated ester obtained by reacting an epoxy resin with an unsaturated basic acid, (b) general formula (
I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1 is a hydrogen atom or a methyl group, and R^2 is an alkylene group with 2 to 12 carbon atoms or an alkylene group with 4 to 12 carbon atoms. and an oxaalkylene group having at least one oxygen atom connecting distant segments of the alkylene group, and in which this segment has at least two carbon atoms. 15
0 parts by weight and (c) General formula (II) ▲Mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, R^1 and R^2 are the same as general formula (I))
A method for producing a molded article, which comprises applying a resin composition containing 5 to 150 parts by weight of the compound represented by the formula above onto a polystyrene foam and curing it. 2. A method for producing a molded article, which comprises laminating the resin composition according to claim 1 together with a reinforcing material on a polystyrene foam and curing the resin composition. 3. (a) 100 parts by weight of an unsaturated ester obtained by reacting an epoxy resin with an unsaturated basic acid, (b) General formula (
I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1 is a hydrogen atom or a methyl group, and R^2 is an alkylene group with 2 to 12 carbon atoms or an alkylene group with 4 to 12 carbon atoms. and an oxaalkylene group having at least one oxygen atom connecting distant segments of the alkylene group, and in which this segment has at least two carbon atoms. 15
0 parts by weight and (c) General formula (II) ▲Mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, R^1 and R^2 are the same as general formula (I))
A resin composition for polystyrene foam comprising 5 to 150 parts by weight of a compound represented by: