JPH0455415A - Resin composition for molding fiber reinforced plastic with gel coat, production of molded article and molded article - Google Patents

Abstract

PURPOSE:To obtain the title composition not causing phase separation by variation with time, not leading to reduction in strength, improving occurrence of sink mark and GARASUME (glass eye), comprising a specific unsaturated polyester resin and a terminal polymerizable unsaturated bond-containing polybutadiene in a specific ratio. CONSTITUTION:The objective composition comprising (A) 100 pts. wt. unsaturated polyester resin prepared by reacting an acid component containing 50-100 mol % tricyclo[5,2,1,0<2.6>] deca-3-en-8-yl-maleate or tricyclo[5,2,1,0<2.6>] deca-3-en-9- yl-maleate with a glycol component containing 30-80 mol % neopentyl glycol to give an unsaturated polyester and dissolving the unsaturated polyester in a polymerizable monomer (e.g. styrene or (meth) acrylic acid] and (B) 3-20 pts. wt. terminal polymerizable unsaturated bond-containing polybutadiene.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a resin composition for molding fiber-reinforced plastics with a gel coat, a method for producing a molded article using the same, and a molded article using the same.

[Conventional technology] Conventionally, gel coated fiber reinforced plastic molded products are
Because the gel coat can be colored and patterned to further enhance its beauty, it is widely used in ships, automobile parts, leisure ports, bathtubs, bathroom units, tanks, etc.
It is manufactured as follows.

First, apply gel coat resin to the surface of the mold by 0.1~0°5 [
The coating is applied to a thickness of about ln using a spray gun, brush, etc., and cured to produce a gel coat. Curing can be done naturally or forcibly in a hardening furnace, and the method is selected depending on the size of each molded product and equipment capacity. A fiber-reinforced plastic (hereinafter abbreviated as FRP) layer made of an unsaturated polyester resin composition and a fiber base material is applied on top of this gel coat using a spray-up method, an and-lay-up method, a resin injection method, a pressure back method, a vacuum back method, etc. After being cured naturally or using a curing furnace, the molded product is removed from the mold to obtain a gel coated FRP molded product.

Such gel-coated FRP molded products have a large degree of freedom in design, so they have the advantage of being able to produce complex and large molded products in a short time. There are problems such as damage to the appearance due to shrinkage.

For example, when FRP layers are laminated and placed in a curing furnace, the phenomenon of natural mold release (sink) before demolding, which often occurs in some corners, and the embossment of the fiber base material that occurs as the FRP on the back side shrinks. A defective phenomenon called glassy eyes) occurs.

Such defects may require polishing or repair to restore and maintain the aesthetic appearance, which increases the number of man-hours and causes an increase in price. In order to prevent these defects, conventional methods have been to reduce shrinkage by adding thermoplastic resins such as polystyrene, polyvinyl acetate, and saturated polyester as low-shrinkage agents, or to slow curing to minimize internal stress. However, these methods have advantages and disadvantages. In the former method, variations in the low shrinkage effect may occur due to uneven thickness or variations in temperature control, resulting in local waviness or glass grains, and if you try to obtain a sufficient low shrinkage effect, the molded product may Often causes a decrease in strength. On the other hand, in the latter method, although the resultant gel-coated FRP molded product has fewer defects, the molding operation time is long, so it is not suitable for the current situation where short-time molding is required.

[Problems to be Solved by the Invention] The present inventors have previously developed a composition of a specific unsaturated polyester resin obtained using an α,β-unsaturated polybasic acid and a polybutadiene containing a terminal polymerizable unsaturated bond. proposed a molded product made of FRP and a fiber base material.

The present invention further improves this, and is a gel-coated FRP molded product using an unsaturated polyester resin composition that does not generate whiskers or glass grains, has sufficient mechanical strength, and has excellent storage stability. An object of the present invention is to provide a resin composition, a method for producing a molded article, and a molded article.

Means for Solving Problem C] The present invention provides (A) tricyclo[5.2,1,02=')
an acid component containing 50 to 100 mol% of dec-3-en-8-yl-maleate or tricyclo[5,2,1,0''.6]dec-3-en-9-yl-maleate;
100 parts by weight of an unsaturated polyester resin obtained by dissolving an unsaturated polyester obtained by reacting a glycol component containing 30 to 80 mol% of neopentyl glycol in a polymerizable monomer, and (B') a terminal polymerizable monomer. The present invention relates to a gel-coated FRP resin composition containing 3 to 20 parts by weight of saturated bond-containing polybutadiene, a method for producing a gel-coated FRP molded article using the same, and a gel-coated FRP molded article using the same.

The unsaturated polyester used in the present invention is tricyclo[5.2,1,O"')dec-3-ene 8 or 9-
It can be synthesized by a known method using an acid component containing 50 to 100 mol % of yl-hydrogen-maleate and a glycol component containing 30 to 80 mol % of neopentyl glycol.

Tricyclo[5,2,1,02"6]deca- in the acid component
If the amount of 3-en-8 or 9-yl-hydrogen maleate is outside the range of 50 to 100 mol%, phase separation of component (B) is likely to occur. This compound is a reaction between maleic acid and dicyclopentadiene, maleic anhydride and 5- or 6-hydroxy-3a.

It can be obtained by reaction with 4.5,6,7.7a-hexahydro-4,7-methanoindene, etc.

Other acid components include unsaturated dibasic acids such as maleic acid, fumaric acid, itaconic acid, and citraconic acid, or their acid anhydrides, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, succinic acid, azelaic acid, Saturated polybasic acids such as adipic acid, tetrahydrophthalic acid, hexahydrophthalic acid, endomethylenetetrahydrophthalic acid, and het's acid, or their acid anhydrides, are used, and two or more of these may be used in combination.

The amount of neopentyl glycol in the glycol component is 30
Outside the range of 80 mol %, phase separation of component (B) is likely to occur.

Other glycol components used include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 23-butanediol, 1.5-bentanediol, 1.6-hexanediol, etc. Two or more types may be used in combination. Furthermore, it is also possible to use trihydric alcohols such as glycerintrimethylolpropane and tetrahydric alcohols such as pentalit.

The reaction between the acid component and the glycol component is mainly carried out by proceeding with a condensation reaction, and the reaction proceeds by distilling water produced when both components react out of the system.

The polymerizable monomers used in the present invention include styrene,
Styrene derivatives such as p-methylstyrene, α-methylstyrene, vinyltoluene, divinylbenzene, chlorostyrene, dichlorostyrene, bromostyrene, dipromostyrene, monomethyl fumarate, dimethyl fumarate,
Alkyl esters of α,β-unsaturated dibasic acids such as monomethyl maleate, dimethyl maleate, monoethyl fumarate, diethyl fumarate, monoethyl maleate, diethyl maleate, dibutyl fumarate, dibutyl maleate, (meth)acrylic acid (meaning methacrylic acid or acrylic acid, the same hereinafter), methyl (meth)acrylate, ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, allyl (meth)acrylate, trimethylolpropane, tri( meth) acrylate (meaning methacrylate or acrylate, the same hereinafter),
Ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1゜6-hexanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, di Cyclopentadiene (meth)
Examples include (meth)acrylic acid or its derivatives such as acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol penta(meth)acrylate, and two or more of these may be used in combination. Good too.

The unsaturated polyester resin used in the present invention is obtained by dissolving a polymerizable monomer in the unsaturated polyester described above.

Although there is no particular restriction on the amount of the polymerizable monomer, it is preferably 30 to 50% by weight based on the unsaturated polyester resin from the viewpoint of workability and molded appearance due to occurrence of sink marks, glass marks, etc.

The unsaturated polyester resin containing components (A) and (B) of the present invention may optionally contain a polymerization inhibitor such as hydroquinone, pyrocatechol, or 2,6-ditertiarybutylvalacresol, cobalt naphthenate, Metal soaps such as cobalt octenoate, quaternary ammonium salts such as dimethylbenzylammonium chloride, β-diketones such as acetylacetone, dimethylaniline, N-
Curing accelerators such as amines such as ethyl metatoluidine and triethanolamine, dyes, pigments, ultraviolet absorbers, thixotropic agents such as silica powder, hydrogenated castor oil, fatty acid amide, fillers, stabilizers, antifoaming agents , various additives such as leveling agents may be used.

The unsaturated polyester resin composition used in the present invention is
It contains 100 parts by weight of the unsaturated polyester resin and 3 to 20 parts by weight of polybutadiene containing terminal polymerizable unsaturated bonds. If the amount of the terminal polymerizable unsaturated bond-containing polybutadiene is less than 3 parts by weight, the molded appearance cannot be improved due to the occurrence of sink marks, glass grains, etc., and if it exceeds 20 parts by weight, the mechanical strength will decrease. Furthermore, when using polybutadienes that do not contain terminal polymerizable unsaturated bonds, low shrinkage properties are obtained similar to thermoplastic resins, and the appearance of molding is improved without the occurrence of sink marks or glass marks, but mechanical strength is reduced. .

Terminal polymerizable unsaturated bond-containing polybutadiene is already a known compound, including terminal methacrylic polybutadiene, terminal acrylic polybutadiene, terminal allyl polybutadiene,
Examples include terminal monomaleate polybutadiene, and two or more of these may be used in combination.

The terminal polymerizable unsaturated bond-containing polybutadiene can be obtained by the method shown below. For example, methods for attaching polymerizable unsaturated bonds to polybutadiene having a hydroxyl group at the terminals by ester bonds include (1) reaction with an acid halide having a polymerizable unsaturated bond; (2) reaction with methyl methacrylate or methyl acrylate; and (3) ring-opening monoesterification reaction with an acid anhydride having a polymerizable unsaturated bond such as maleic anhydride. Alternatively, a polybutadiene having a hydroxyl group at the end is reacted with a glycidyl compound having a polymerizable unsaturated bond, and the polybutadiene is reacted with an isocyanate compound having a polymerizable unsaturated bond, and the polybutadiene is reacted with an isocyanate compound having a polymerizable unsaturated bond, and the polybutadiene is reacted with a glycidyl compound having a polymerizable unsaturated bond. Polybutadiene containing terminal polymerizable unsaturated bonds is obtained in each case. Alternatively, polybutadiene having a hydroxyl group at the end is reacted with a diisocyanate compound to first form a polybutadiene having an isocyanate group at the end, and then a polymerizable unsaturated bond and a compound having a hydroxyl group are reacted to form a terminal polymerizable compound via a urethane bond. A polybutadiene containing saturated bonds is obtained. On the other hand, a polybutadiene having a terminal carboxyl group is reacted with a glycidyl compound having a polymerizable unsaturated bond to obtain a polybutadiene having a terminal polymerizable unsaturated bond via an ester bond.

The fine structure of the polybutadiene moiety of the polybutadiene having a hydroxyl group or a carboxyl group at the terminal used herein is used regardless of the ratio of 1.4-cis, 1.4-)lance, and 1.2-vinyl. It is possible.

As a product name, for example, TE-2000 manufactured by Sunkasei Co., Ltd.
TE-3000 (both terminal methacrylate polybutadiene).

The fiber base materials used in the present invention include glass fibers such as glass chopped strand cloak, glass cloth, glass roving, and glass surface mat, and carbon fibers such as carbon filament chopped strand mat, carbon filament cloth, and carbon filament roving. Examples include organic fibers such as fibers, nonwoven fabrics, nylon fibers, and Tetron fibers, and two or more of these may be used in combination.

The gel coated FRP molded product of the present invention is produced by applying a commercially available gel coat resin to the surface of a mold by a known method and curing it, and then applying the above-mentioned polybutadiene-containing resin composition and fiber base material thereon. It is obtained by laminating FRP layers by a known method, curing them, and demolding them.

For curing of the molding resin composition, organic peroxide catalysts such as methyl ethyl ketone peroxide, benzoyl peroxide, cumene hydroperoxide, and lauroyl peroxide, diphenyl disulfide, hengeine, benzoin methyl ether, hengeine ethyl ether, and benzoin isopropylene are used. Photopolymerization initiators such as building ether and dimethylbenzylkecoel are used. These photopolymerization initiators and organic peroxides may be used in combination.

[Example] Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, in the examples, "parts" indicate parts by weight.

(1) Synthesis of unsaturated polyester resin (A) 21 equipped with a stirrer, condenser, nitrogen gas introduction pipe and temperature needle
738 parts of maleic acid and 720 parts of dicyclopentadiene were placed in a 4-hole flask and reacted for 2 hours at 130°C under a nitrogen stream.

The acid value of this product was 282. After cooling, 149 parts of endomethylenetetrahydrophthalic anhydride, 260 parts of neopentyl glycol, 185 parts of propylene glycol, and 0.42 parts of hydroquinone were charged, and a mantle heater was used to slowly flow nitrogen gas to heat the mixture for 1 hour.
The temperature was raised to 0'C and then further raised to 210C over 4 hours. The mixture was kept at that temperature for 6 hours to obtain an unsaturated polyester having an acid value of 29. 75 parts of the obtained unsaturated polyester was dissolved in 25 parts of styrene in which 5 parts of hydroquinone O, OO had been dissolved in advance to form an unsaturated polyester resin (A
) was obtained.

(2) Synthesis of unsaturated polyester resin (B) 21 equipped with a stirrer, condenser, nitrogen gas introduction pipe and thermometer
04th flask, 836 parts of propylene glycol,
740 parts of phthalic anhydride and 490 parts of maleic anhydride were charged, and the temperature was raised to 150°C in 1 hour using a mantle heater while slowly flowing nitrogen gas, and then to 210°C over a further 4 hours. The mixture was kept at that temperature for 7 hours to obtain an unsaturated polyester having an acid value of 32. 70 parts of the obtained unsaturated polyester was mixed with 0.0 parts of hydroquinone in advance.
An unsaturated polyester resin (B) was obtained by dissolving 2 parts in 30 parts of styrene.

(3) Synthesis of monomaleated polybutadiene G-1000 (manufactured by Suna Kasei Co., Ltd., terminal hydroxy polybutadiene, Hydroxyl value 72.
4KOHmg/g), 96g of maleic anhydride, and 0.27g of hydroquinone, and heated under a nitrogen stream for 1 hour.
The reaction was carried out at 20'C for 1.5 hours to obtain terminal monomaleate polybutadiene (hereinafter abbreviated as PBMA) having an acid value of 61.3 KOH/g/g and a hydroxyl value of 4.3 KOH/g.

Examples 1 to 4 and Comparative Examples 1 to 4 Polycera l-682PH (manufactured by Hitachi Chemical Co., Ltd., trade name,
Add 1 part of Permec N (manufactured by NOF Corporation, 55% methyl ethyl ketone peroxide) to 100 parts of unsaturated polyester resin), mix, and then spray this into the stainless steel mold shown in Figure 1 with a spray gun (caliber 2.5). 5 mm) to a thickness of 0.3 mm, and
A gel coat layer was prepared by curing in a constant temperature bath at 0°C for 50 minutes.

After cooling, the glass content becomes 33% by weight using each unsaturated polyester resin composition having the formulation shown in Table 1 and FEM-450 (manufactured by Fuji Fiberglass Co., Ltd., glass chopped strand mat). It was laminated on the above gel coat layer by hand lay-up molding while making the following adjustments, immediately placed in a constant temperature bath at 50°C, cured for 50 minutes, and immediately demolded to obtain a gel coated FRP molded product.

The length of the beard at a part of the corner of this gel-coated FRP molded product was measured using a caliper, and the presence or absence of glass was visually observed. In addition, tensile strength and impact strength were measured according to JIS K6911 using specimens cut from this gel coated FRP molded product, and each unsaturated polyester resin composition with the formulation shown in Table 1 was 1
Pour into a 6mm test tube to a height of 1Qcm and seal it for 25 minutes.
The sample was left at 1 day at °C, and the thickness of the phase-separated upper layer of the polybutadiene containing terminal polymerizable unsaturated bonds was measured using a caliper. These results are shown in Table 1.

From Table 1 below, it can be seen that the molded products of Examples have less sink marks than Comparative Examples, no glass grains or layer separation (and have excellent mechanical properties). .

[Effects of the Invention] According to the resin composition for FRP molding with a gel coat according to the present invention, it does not cause phase separation due to changes over time, does not cause a decrease in mechanical strength or increase in working time, and is superior to conventional molded products. , the occurrence of whiskers and glass grains can be significantly improved, and even when manufacturing molded products that require aesthetic appearance, the number of reworks due to polishing and repair can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a mold for a gel coated FRP molded product.

Claims (1)

[Claims] 1. (A) Tricyclo (5.2.1.0^2^,^6]
deca-3-en-8-yl-malayate or tricyclo[5.2.1.0^2^,^6]dec-3-ene-
An unsaturated polyester obtained by reacting an acid component containing 50 to 100 mol% of 9-yl maleate with a glycol component containing 30 to 80 mol% of neopentyl glycol is dissolved in a polymerizable monomer. 100 parts by weight of unsaturated polyester resin and (B) 3 to 2 parts of terminal polymerizable unsaturated bond-containing polybutadiene
A gel coated fiber reinforced plastic molding resin composition containing 0 parts by weight. 2. After applying a gel coat resin to the surface of the mold and curing, a fiber reinforced plastic layer is laminated thereon using the gel coated fiber reinforced plastic molding resin composition according to claim 1 and a fiber base material and cured. , a method for manufacturing fiber-reinforced plastic molded products with a gel coat that is demolded. 3. A fiber-reinforced plastic molded product with a gel coat, comprising a fiber-reinforced plastic layer containing the resin composition for molding fiber-reinforced plastic with a gel coat according to claim 1 and a fiber base material on the back side of the gel coat.