JP2002105155A - Resin composition for frp molded material having gel coat and method for producing the same material having gel coat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an FRP molded material having a gel coat, capable of producing the molded product excellent in rigidity and adoptable for a wide fields easily and in a good working efficiency. SOLUTION: This resin composition for the FRP molded material contains (1) 100 pts.wt. unsaturated polyester resin obtained by dissolving an unsaturated polyester obtained by reacting (a) (a) mol polyethylene-2,6-naphthalate (provided that it is a number of moles of the 2,6-naphthalene dicarboxylic acid contained in its molecule), (b) (b) mol α,β-unsaturated dibasic acid, (c) (c) mol saturated polybasic acid and (d) (d) mol polyhydric alcohol so that a/(a+b+c) becomes (0.05/1)-(0.9/1) and (a+d)/(a+b+c) becomes (1/1)-(3/1), with a polymerizable monomer, (2) 3-30 pt.wt. polybutadiene having a polymerizable unsaturated bond at its terminal and (3) 0.3-2 pt.wt. curing agent for a middle temperature. The method for producing the FRP molded material having a gel coat by using the above resin composition is also provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a gel coat F
The present invention relates to a resin composition for an RP (fiber reinforced plastic) molded product and a method for producing an FRP molded product with a gel coat.

[0002]

2. Description of the Related Art FRP molded products with gel coat are known as FRP
There is a drawback that unevenness occurs on the surface of the gel coat due to the effect of the glass fiber of the layer. In order to solve this drawback, it is effective to use a low-shrinkable unsaturated polyester resin composition for the FRP layer. Unevenness may occur in the smoothness, and it is limited to application to some molded products.

[0003] A method using a tough vinyl ester resin has also been proposed. However, it has been improved only slightly, and a beautiful gel coat surface can be formed stably. The emergence of a production method suitable for the production of articles is desired.

[0004]

SUMMARY OF THE INVENTION The invention according to claim 1 is an FRP with a gel coat which is excellent in laminating workability and curability, has excellent rigidity and can produce a molded article applicable to a wide range of fields.
A resin composition for a molded article is provided. The invention according to claim 2 is an FRP with a gel coat that can easily produce a molded article having excellent rigidity and applicable to a wide range of fields with good workability.
A method for producing a molded article is provided.

[0005]

The present invention provides (1) (a)
A mole of polyethylene-2,6-naphthalate (provided that the number of moles of the 2,6-naphthalenedicarboxylic acid component contained in the molecule) and (b) α, β-unsaturated dibasic acid and / or an acid anhydride thereof b mol, (c) c mol of a saturated polybasic acid and / or an acid anhydride thereof, and (d) d mol of a polyhydric alcohol, a / (a + b + c) is 0.05 / 1 to
0.9 / 1, (a + d) / (a + b + c) is 1/1 to 3
/ 100 parts by weight of an unsaturated polyester resin obtained by dissolving an unsaturated polyester obtained by blending and reacting to a polymerizable monomer in a polymerizable monomer, and (2) polybutadiene having a polymerizable unsaturated bond at a terminal. 20 parts by weight and (3)
The present invention relates to a resin composition for gel-coated FRP molded articles, containing 0.3 to 3 parts by weight of a curing agent for medium-temperature molding.

The present invention is also directed to the production of a gel coat layer and a fiber reinforced plastic molded article with a gel coat in which a fiber reinforced material is present on the surface of the gel coat layer to cure a cured resin to form an intermediate layer and a reinforcing layer in order. In the method,
The intermediate layer is formed from the resin composition for an FRP molded article with a gel coat.
The present invention relates to a method for manufacturing an RP molded product.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The unsaturated polyester in (1) the unsaturated polyester resin in the resin composition for gel-coated FRP molded articles of the present invention is (a) polyethylene-2,
6 moles of 6-naphthalate (however, the number of moles of the 2,6-naphthalenedicarboxylic acid component contained in the molecule);
(B) b mol of α, β-unsaturated dibasic acid and / or acid anhydride thereof, (c) c mol of saturated polybasic acid and / or acid anhydride thereof, and (d) d mol of polyhydric alcohol. And a
/ (A + b + c) is 0.05 / 1 to 0.9 / 1, (a +
d) It is obtained by blending and reacting so that / (a + b + c) becomes 1/1 to 3/1.

[0008] In the above (a) polyethylene-2,6-naphthalate, (a + d) / (a + b + c) is 1/1 to 3 /
1.03 / 1 to 1.2
It is preferable to be blended so as to be in the range of / 1.
If (a + d) / (a + b + c) is less than 1/1, the depolymerization of polyethylene-2,6-naphthalate is unlikely to occur, and if it exceeds 3/1, the curability decreases.

A / (a + b + c) is 0.05 / 1
~ 0.9 / 1, 0.05 / 1 ~ 0.6
/ 1 is preferred. a / (a + b
When + c) is less than 0.05 / 1, the smoothness of the surface of the gel coat decreases, and when it exceeds 0.9 / 1, (1) the viscosity of the unsaturated polyester resin increases sharply, and the laminating workability is remarkably increased. Lower.

The (a) polyethylene-2,6-naphthalate (hereinafter abbreviated as PEN) may not be a polymer material before molding. For example, scraps generated during PEN production, PEN molded products such as film bottles, wastes such as defective scraps generated in the production process, discarded objects, collected used films and bottles can be used. . When a recovered product such as a film or a bottle is used, it is preferably crushed into 30 mm square or less, preferably 10 mm square or less, washed, and dried so that polyhydric alcohol decomposition proceeds promptly. One mole of PEN indicates a repeating unit and corresponds to a molecular weight of 242.

The above-mentioned (b) unsaturated dibasic acid and / or anhydride thereof includes, for example, maleic acid, fumaric acid,
Itaconic acid, citraconic acid, maleic anhydride and the like can be used. These are used alone or in combination of two or more.

The above-mentioned (b) unsaturated dibasic acid and / or acid anhydride thereof has b / (a + b + c) of 0.1 / 1 to 0.9.
It is preferably used in the range of 5/1,
More preferably, it is used in the range of 0.9 / 1. If the amount is too small, the smoothness of the gel coat surface tends to decrease, and if it exceeds 0.95 / 1, the effect of using PEN is lost, and the smoothness of the gel coat surface tends to decrease.

The above (c) saturated dibasic acid and / or acid anhydride thereof includes, for example, phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid-trimellitic acid, trimellitic anhydride, succinic acid, azelaic acid, adipine Acid, tetrahydro-phthalic acid, tetrahydro-phthalic anhydride,
Hexahydro-phthalic acid, hexahydro-phthalic anhydride, rosin-maleic anhydride adduct, chlorendic acid, chlorendic anhydride, tetrachlorophthalic acid, tetrachlorophthalic anhydride, tetrabromophthalic acid, tetrabromomo And phthalic anhydride. These are used alone or in combination of two or more.

(C) The saturated dibasic acid and / or its acid anhydride is c / (a + b +
c) is preferably used in the range of 0.05 / 1 to 0.85 / 1, and more preferably in the range of 0.05 / 1 to 0.65 / 1.

The polyhydric alcohol (d) includes, for example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol,
Examples thereof include 3-butanediol, 1,6-hexanediol, neopentyl glycol-triethylene glycol, isopentyl glycol-trimethylolpropane, and the like. These are used alone or in combination of two or more.

(D) The polyhydric alcohol must be used,
Regarding the amount used, the amount of the component (a) is (a +
d) / (a + b + c) is as described above.

The polymerizable monomer used for dissolving (1) the unsaturated polyester in the present invention includes, for example, styrene, vinyltoluene, p-methylstyrene,
Styrene derivatives such as α-methylstyrene, vinyltoluene, vinylbenzene, chlorostyrene and dichlorostyrene, monomethyl fumarate, dimethyl fumarate, monomethyl maleate, dimethyl maleate, monoethyl fumarate, diethyl fumarate, monoethyl maleate, maleate Alkyl esters of {,}-unsaturated dibasic acids such as diethyl acrylate, dibutyl fumarate, dibutyl maleate, etc., methyl acrylate, ethyl acrylate, hydroxyethyl acrylate, allyl acrylate, tris (2-hydro- (Xyethyl) isocyanuric acid acrylate, neopentyl glycol diacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, 1,9-nonanedi And acrylic acid derivatives such as tris (2-hydroxyethyl) isocyanuric acid acrylate, and methacrylic acid derivatives, acrylic acid, and methacrylic acid corresponding to these acrylic acid derivatives. You. These are used alone or in combination of two or more.

The amount of the polymerizable monomer is not particularly limited. However, in consideration of workability, sink marks, and appearance of molding such as glass grain, (1) the amount of the polymerizable monomer is preferably 30 to 30% based on the unsaturated polyester resin.
Preferably, it is 50% by weight.

When curing the unsaturated polyester resin (1) in the present invention, a room temperature curing agent may be used. Examples of the room-temperature curing agent include ketone peroxide-based curing agents such as methyl ethyl ketone peroxide and acetylacetone peroxide, and hydroperoxide. (1) The unsaturated polyester resin is heated at 5 to 40 ° C. in combination with a curing accelerator. A curable curing agent can be used. Examples of the curing accelerator include quaternary ammonium salts such as dimethylbenzylammonium chloride, β-diketones such as acetylacetone, dimethylaniline, and N-ethyl-.
Examples include amines such as metatoluidine-triethanolamine. As the curing agent, a ketone peroxide-based curing agent is preferable, and as the curing accelerator, metal soaps such as cobalt naphthenate and cobalt octenoate are more preferable.

The (1) unsaturated polyester resin in the present invention may contain, if necessary, a polymerization inhibitor such as hydroquinone, pyrocatechol, 2,6-di-tert-butylparacresol, a dye, a pigment, and an ultraviolet absorber. , Silica powder (commercially available under the trade name of Aerosil-200 from Nippon Aerosil Co., Ltd.), thixotropic agent such as hydrogenated castor oil, aliphatic amide, filler, stabilizer, defoamer, leveling agent And the like.

The (2) polybutadiene having a polymerizable unsaturated bond at the terminal in the present invention is a known compound, and examples thereof include an acrylic polybutadiene, a methacrylic polybutadiene, an allyl polybutadiene and a monomalate polybutadiene. Are used alone or in combination of two or more.

The (2) polybutadiene having a polymerizable unsaturated bond at a terminal in the present invention can be obtained by the following method or the like. For example, as a method of attaching a polymerizable unsaturated bond to a polybutadiene having a hydroxyl group at a terminal by an ester bond, a reaction with an acid halide having a polymerizable unsaturated bond, a transesterification reaction with methyl methacrylate or methyl acrylate, an anhydride reaction A ring opening monoesterification reaction with an acid anhydride having a polymerizable unsaturated bond such as maleic acid and the like can be mentioned.

Further, a polytadiene having a hydroxyl group at a terminal is reacted with a glycidyl compound having a polymerizable unsaturated bond, and an isocyanate compound having a polymerizable unsaturated bond with an ether bond or with the polybutadiene is reacted with the polybutadiene. The reaction is performed to obtain polybutadiene having a polymerizable unsaturated bond at each terminal via a urethane bond. Alternatively, a polybutadiene having a hydroxyl group at the end is reacted with a diisocyanate compound, first, a polybutadiene having an isocyanate group at the end is reacted with a compound having a polymerizable unsaturated unsaturated bond and a hydroxyl group, and a urethane bond is formed. Polybutadiene having a polymerizable unsaturated bond at a terminal is obtained.

On the other hand, a polybutadiene having a carboxyl group at a terminal is reacted with a glycidyl compound having a polymerizable unsaturated bond to obtain a polybutadiene having a polymerizable unsaturated bond at a terminal via an ester bond. The polybutadiene portion having a hydroxyl group or a carboxyl group at the terminal used herein has a fine structure of 1,4.
Any proportion of -cis, 1,4-trans and 1,2-vinyl can be used. Commercially available products include, for example, TE-20 manufactured by Nisso Chemicals, Inc.
And E-3000 (both are terminal methacrylate polybutadienes).

The compounding amount of (2) the polybutadiene having a polymerizable unsaturated bond at the terminal in the present invention is in the range of 3 to 20 parts by weight with respect to (1) 100 parts by weight of the unsaturated polyester resin. If the amount is less than 10 parts by weight, no improvement in the appearance of molding such as sink marks and glass eyes is observed, and if it exceeds 20 parts by weight, the mechanical strength decreases. In addition, when polybutadiene having no polymerizable unsaturated bond at the terminal is used, low shrinkage is obtained as in the case of thermoplastic resin, and molding appearance such as sink marks and glass eyes is improved, but mechanical strength is reduced. I do.

As the curing agent (3) in the present invention, for example, an organic peroxide having a temperature at which the amount of active oxygen decomposes to half in 10 hours (half-life temperature) is 30 to 80 ° C. is used. Is preferred.

Examples of such organic peroxides include, for example, t-hexylperoxyhexanate and t-butylperoxy-2-ethylhexanate (available from Nippon Oil & Fats Co., Ltd. under the trade name of Percure HO). Yes), 1,
Peroxyester organic peroxides such as 1,3,3-tetramethylbutylperoxy 2-ethylhexyl hexanate, bis (4-t-butylcyclo-hexyl) peroxydicarbonate, di-2-methoxybutyl peroxy Organic peroxides such as peroxydicarbonates such as oxydicarbonate and di (2-methyl-3-methoxybutyl) peroxydicarbonate; and diacyl peroxides such as 3,5,5-trimethylhexanoyl peroxide and octanoyl peroxide Oxide-based organic peroxides and the like.

The amount of the (3) curing agent for medium temperature molding added is in the range of 0.3 to 3.0 parts by weight based on 100 parts by weight of the unsaturated polyester resin (1). If the amount is less than 0.3 parts by weight, the curability deteriorates and the smoothness of the gel coat surface is reduced. If the amount is more than 3.0 parts by weight, sinks occur in the corner of the gel coat surface and the FRP with a beautiful gel coat is formed.
Molded products cannot be obtained.

The production of a gel-coated FRP molded product will be described below with reference to FIGS. FIG. 1 shows a mold 1. After a commercially available gel coat resin is applied to the surface of the mold 1 by a known method and cured to form a gel coat layer 2, the gel-coated FRP molded resin composition of the present invention and a fiber base material are further coated thereon by a known method. The intermediate layer 3 formed by lamination and gelation by a method is further formed, and a commercially available unsaturated polyester resin and a fiber base material are laminated thereon by a known method and cured to form a reinforcing layer 4, and the mold is removed. FRP with gel coat
A molded article can be obtained (FIG. 2).

There is no particular limitation on the fiber reinforcing material used here, and for example, glass fiber, carbon fiber, aramid fiber and the like can be used. There is no special restriction on the use form of these fibers, for example, in a chopped strand mat, a mat form such as a continuous mat, a cross continuous fiber form such as a glass roving cloth, and a roving form such as a glass roving. It is possible to use.

The ratio of the fiber reinforcing material in the mid layer 3 is 1
It is preferably from 5 to 50% by weight, more preferably from 20 to 40% by weight. And the thickness of this intermediate layer 3 is
0.3 to 3 mm is preferable, and 0.5 to 2.0 mm is more preferable. The ratio of the fiber reinforcing material in the reinforcing layer 4 is 15 to 6
0% by weight, preferably 20 to 50% by weight
Is good. The thickness of the reinforcing layer 4 is 0.5 to 10
mm is preferable, and 1.0 to 7.0 mm is particularly preferable.

As shown in FIG. 2, an example of a molded article obtained by using the resin composition for gel-coated FRP molded article of the present invention has a gel coat layer 2 as a surface and a fiber reinforcing material inside (lower layer). F with a three-layer gel coat F provided with a resin intermediate layer 3 and a reinforcing layer 4
It is an RP molded product.

[0033]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

(1) Preparation of unsaturated polyester resin A Propylene glycol 857 g (11.2 mol), neopentyl glycol 305 g (2.93 mol), PE
N355 g (1.47 mol, 2,6
-Naphthalenedicarboxylic acid conversion, the same applies hereinafter), 0.365 g of t-butyl titanate (0.1% of PEN weight),
487 g (2.93 mol) of isophthalic acid was added to 3,0
The mixture was charged in a 00 ml four-necked flask and heated to 210 ° C. over 5 hours while stirring under a nitrogen stream. When the contents became uniform, the temperature was lowered to 180 ° C. At this time, no remarkable reflux of glycol was observed. The number average molecular weight of this depolymer (measured in terms of standard polystyrene using gel permeation chromatography, the same applies hereinafter) was 680.

At 180 ° C., 1,006 g of maleic anhydride
(10.3 mol) and 0.3 g of hydroquinone,
The temperature was raised again to 215 ° C. in 3 hours, a dehydration condensation reaction was carried out by a conventional method. When the acid value reached 23 KOH mg / g, the reaction was stopped, and at 170 ° C., styrene 1 containing 0.4 g of hydroquinone was added. The resin was dissolved in 500 g to obtain an unsaturated polyester resin A. The number average molecular weight of the product was 2,100.

(2) Preparation of unsaturated polyester resin B 429 g (5.6 mol) of propylene glycol, 289 g (2.8 mol) of neopentyl glycol, PEN
1,009 g (4.2 mol), t-butyl titanate 1.01 g (0.1% of PEN weight), isophthalic acid 2
31 g (1.4 mol) was charged into a 3,000 ml four-necked flask equipped with a thermometer, a stirrer, an inert gas inlet tube, and a condenser, and stirred under a nitrogen stream for 5 hours while stirring. C., and when the contents became uniform, the temperature was lowered to 180.degree. At this time, no remarkable reflux of glycol was observed. The number average molecular weight of this depolymer was 690.

At 180 ° C., 817 g of maleic anhydride
(8.3 mol), 232 g of propylene glycol
(3.1 mol), 0.3 g of hydroquinone was added, the temperature was raised again to 215 ° C. in 3 hours, a dehydration condensation reaction was carried out by a conventional method, and the reaction was stopped when the acid value reached 22 KOHmg / g. The polymer was dissolved in 1,500 g of styrene to which 0.4 g of hydroquinone was added at 170 ° C. to obtain an unsaturated polyester resin B. The number average molecular weight of this product was 2,000.

(3) Preparation of Terminal Monomalate Polybutadiene G-1000 (manufactured by Nisso Chemical Co., Ltd., terminal hydroxy polybutadiene, supplied with a stirrer, condenser, nitrogen gas inlet tube and thermometer) Hydroxyl value 72.4 KOHmg / g) 800 g, maleic anhydride 96
g and hydroquinone 0.27 g, and reacted at 120 ° C. for 1.5 hours under a nitrogen stream, with a participation of 61.3 KOHmg /
g, a terminal monomalate polybutadiene (hereinafter abbreviated as PBMA) having a hydroxyl value of 4.3 KOH mg / g was obtained.

First, Polyset 682PH (trade name of unsaturated polyester resin composition manufactured by Hitachi Chemical Co., Ltd.)
Permec N (Nippon Oil & Fats Co., Ltd. 5
1 part by weight of methyl ethyl ketone peroxide (5% by weight) was added, and after mixing, the mixture was sprayed into a molding die (with a caliber of 2.
5 mm) to a thickness of 0.3 mm, and this was cured with a dryer at 50 ° C. for 50 minutes. After cooling, the glass content is reduced to 25% by weight using a resin composition for gel-coated FRP molded articles having the composition shown in Table 1 below and FEM-230 (glass chopped strand mat manufactured by Nitto Boseki Co., Ltd.). The layers were laminated by a hand lay-up molding method while adjusting as described above to obtain an intermediate layer (before curing).

After gelation of the intermediate layer, polyset 5595A
PT-M (trade name of unsaturated polyester resin composition manufactured by Hitachi Chemical Co., Ltd.) and FEM-450 (Nittobo Co., Ltd.
Using a glass chopped strand mat), the layers were laminated by a hand lay-up molding method while adjusting the glass content to 33% by weight, and immediately placed in a dryer at 50 ° C.
Immediately after curing for 0 minutes, the mold was released to obtain an FRP molded article with a gel coat. Tables 1 and 2 show the compositions and properties of the examples and comparative examples.

[0041]

[Table 1]

[0042]

[Table 2]

[Evaluation Method] (1) Sinking The presence or absence of sink marks was visually evaluated. (2) Ashland Indices X Ashland Chemical Co., Ltd.
Measured using A). (The smaller the numerical value, the less irregularities on the surface.) (3) Tensile strength Measured according to JIS K 7113.

[0044]

The resin composition for gel-coated FRP molded articles according to claim 1 is excellent in laminating workability and curability, is excellent in rigidity, and can produce molded articles applicable to a wide range of fields. The method for producing a gel-coated FRP molded product according to the second aspect is capable of easily producing a molded product having excellent rigidity and applicable to a wide range of fields with good workability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a mold that can be used in the present invention.

FIG. 2 is a cross-sectional view of an example of an FRP molded product with a gel coat according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold 2 Gel coat layer 3 Intermediate layer 4 Reinforcement layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 67:06 B29C 67/14 K F term (Reference) 4F072 AA04 AA08 AB06 AB09 AB10 AB28 AB29 AD04 AD05 AD39 AK13 AK14 AK20 AL09 4F205 AA41A AA46 AB03 AD16 AG07 HA03 HA04 HA22 HA33 HA35 HB01 HB13 HC16 HT04 4J027 AA04 AB02 AB05 AB06 AB07 AB08 AB15 AB16 AB17 AB18 AB19 AB23 AB24 AB25 BA04 BA05 BA07 BA08 BA19 BA23 BA28 CB04 CC02 CD02

Claims (2)

[Claims] (1) (1) (a) amol of polyethylene-2,6-naphthalate (provided that 2,6
-Mol number of naphthalenedicarboxylic acid component), and (b)
b mol of α, β-unsaturated dibasic acid and / or acid anhydride and (c) saturated polybasic acid and / or acid anhydride c
Mole and (d) d mole of polyhydric alcohol by a / (a
+ B + c) is 0.05 / 1 to 0.9 / 1, (a + d) /
100 parts by weight of an unsaturated polyester resin obtained by dissolving an unsaturated polyester obtained by blending and reacting (a + b + c) so as to be 1/1 to 3/1 in a polymerizable monomer,
(2) 3 to 20 parts by weight of polybutadiene having a polymerizable unsaturated bond at the terminal and (3) curing agent for medium-temperature molding
A resin composition for an FRP molded article with a gel coat, comprising 3 to 3 parts by weight. 2. A method for producing a gel-coated fiber-reinforced plastic molded article having a gel coat layer and an intermediate layer and a reinforcing layer formed in this order on the surface of the gel coat layer, wherein the intermediate layer is used for the gel-coated FRP molded article according to claim 1. A method for producing an FRP molded article with a gel coat, characterized by being formed using a resin composition.