JP3071585B2 - Unsaturated polyester resin composition, molding material and molded product - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a high-surface-quality, fast-curing unsaturated polyester resin composition having excellent storage stability useful as an outer panel for automobiles, exterior parts, etc. The present invention relates to a sheet-like or bulk-like molding material impregnated with fibers and a molded product obtained by curing the molding material.

[0002]

2. Description of the Related Art A fiber reinforced plastic (FRP) using an unsaturated polyester resin composition has excellent mechanical strength, heat resistance, water resistance, chemical resistance and high productivity. Widely used for tank panels, wash bowls, etc. 2. Description of the Related Art In recent years, unsaturated polyester sheet molding compounds (SMC) or bulk molding compounds (BMC) have been spotlighted as plastic materials for automobile outer panels, for example, spoilers in addition to main outer panels such as engine hoods, roofs and trunk lids. , Air intakes, rocker panels, and other exterior parts.

[0003] SMC or BMC used for automobile outer panels
In particular, high surface quality, rapid curing, and high productivity are required. If the curing speed of SMC and BMC can be increased even in seconds, productivity is remarkably improved. Therefore, various proposals have been made on a fast-curing catalyst (for example, US Pat.
P4278558). However, in general, SMC, B
If the curability of MC is accelerated, its surface smoothness and storage stability tend to be impaired. Regarding the surface smoothness of SMC and BMC, the surface smoothness can be improved by blending a thermoplastic resin such as polymethyl methacrylate, polyvinyl acetate, styrene butadiene block copolymer or the like as a low shrinkage agent. It has been reported that when the curing speed is increased, the surface smoothness can be improved by blending an alkane polyol polyacrylate or an alkane polyol polymethacrylate (JP-A-01-315458). . On the other hand, the storage stability is significantly impaired as the curing speed is increased, and PBQ
The addition of a large amount of a polymerization inhibitor such as (parabenzoquinone) enhances the storage stability, but significantly delays the start of the curing reaction, reversely inhibits rapid curing, and significantly deteriorates the surface smoothness. Invite. Ensuring storage stability as described above is one of the major barriers to the development of a molding material having both fast curing properties and high surface quality.

[0004]

The problem to be solved by the present invention is to provide a molding material with high surface quality, quick curing and excellent storage stability.

[0005]

Means for Solving the Problems The present invention has the following aspects.
Unsaturated polyester resin, vinyl monomer, BHT (di-tert-butylhydroxytoluene), thermoplastic resin, at least one organic peroxide as a reaction initiator, and a compound having a polymerization inhibiting action at a temperature of 100 ° C. or higher 2) a molding material obtained by impregnating glass fiber with the unsaturated polyester resin composition; and 3) a molding obtained by curing the molding material.

The above unsaturated polyester resin composition 1)
Has excellent mechanical strength, heat resistance, water resistance, and chemical resistance, and has high surface quality (surface smoothness, paintability) and rapid curing (production ) And very good storage stability. Also, 100 parts by weight of the unsaturated polyester resin composition and 100 to 250 parts by weight of a filler (for example, calcium carbonate) are mixed with glass fiber (for example, having a length of 1/2 to 4 inches) in an amount of 10 to 40% by weight based on the total composition. The sheet-like or bulk-like molding material 2) obtained by impregnating the glass fiber so as to satisfy the following condition is useful as a molding material for producing automobile outer panels and exterior parts. Further, this molding material has a fast curing property, a very good storage stability, and a molded article having extremely excellent surface smoothness (extremely few sinks or undulations of ribs and bosses). .

The unsaturated polyester resin used in the present invention is synthesized by condensation of an α, β-olefinic unsaturated dicarboxylic acid and a divalent glycol, and has been widely used. In the synthesis of the unsaturated polyester resin, a saturated dicarboxylic acid, an aromatic dicarboxylic acid or dicyclopentadiene which reacts with a carboxylic acid can be used in addition to these two components.

Examples of α, β-olefinically unsaturated dicarboxylic acids include maleic acid, fumaric acid, itaconic acid, citraconic acid and anhydrides of these dicarboxylic acids. Examples of dicarboxylic acids used in combination with these α, β-olefin unsaturated dicarboxylic acids include adipic acid, sebacic acid, succinic acid, gluconic acid, phthalic anhydride, o
-Phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, tetrachlorophthalic acid and the like.

Examples of divalent glycols include alkanediol, oxaalkanediol, bisphenol A
And diols to which ethylene oxide or propylene oxide is added. In addition, a monol or trivalent triol may be used. Examples of alkanediols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, , 6-hexanediol, cyclohexanediol and the like.
Examples of the oxaalkanediol include dioxyethylene glycol, trioxyethylene glycol, and the like. Examples of the monohydric or trihydric alcohol used in combination with these glycols include octyl alcohol, oleyl alcohol, and trimethylolpropane.

The synthesis of an unsaturated polyester resin is generally carried out under heating, and the reaction proceeds while removing by-produced water. In the present invention, the average molecular weight is usually 800 to 400.
0 and an acid value of 20 to 60 are used.

The vinyl monomer used in the present invention includes monovinyl monomers, for example, aromatic monovinyl monomers such as styrene, p-chlorostyrene and vinyltoluene, acrylic acid, methyl acrylate, methacrylic acid, and the like.
Acrylic monovinyl monomers such as methacrylic acid methyl ester and acrylonitrile can be mentioned. These vinyl monomers are usually compounded as a diluent in the unsaturated polyester resin described above and the thermoplastic resin described later.

The BHT (di-tert-butylhydroxytoluene or 2,6-di-tert-butyl-4-methylphenol) used in the present invention can be used for industrial purposes or for food addition. BHT is at room temperature (25
C) to about the aging temperature of SMC (40 ° C), the effect of capturing a trace amount of radicals generated from the organic peroxide added as a polymerization initiator is very strong, and the storage stability of SMC is remarkably improved. On the other hand, around the molding temperature of SMC (12
(0-160 ° C.), the radical scavenging action is very weak and does not cause a delay in the curing reaction. Also, it has no adverse effect on the surface smoothness. Compounds exhibiting a polymerization inhibitory action at a temperature of 100 ° C. or higher include, for example, p-benzoquinone, naphthoquinone, phenanthraquinone, p-xyloquinone,
-Toluquinone, 2,6-dichloroquinone, 2,5-diphenyl-p-benzoquinone, 2,5-diacetoxy-p
Quinones such as -benzoquinone, 2,5-dicaproxy-p-benzoquinone, 2,5-diasiloxy-p-benzoquinone, and, for example, hydroquinone, pt-butylcatechol, 2,5-t-butylhydroquinone, mono-
Hydroquinones such as t-butylhydroquinone and 2,5-di-t-amylhydroquinone are exemplified. Among them, PBQ is preferable. These amounts are 0.001-0.1 parts by weight based on 100 parts by weight of the total of unsaturated polyester resin, vinyl monomer, BHT and thermoplastic resin,
Preferably it is 0.005-0.05 weight part.

As the thermoplastic resin used in the present invention, there can be mentioned a thermoplastic resin conventionally used as a low shrinkage agent for unsaturated polyester resins. Examples of such thermoplastic resins include polybutadiene or its hydrogenated product, polyisoprene or its hydrogenated product, aromatic vinyl / conjugated diene block copolymer or its hydrogenated product, polystyrene, styrene / acetic acid There are vinyl block copolymer, polyvinyl acetate and polymethyl methacrylate, and furthermore, saturated polyester (molecular weight 300 to 100).
000), polyether and the like. Among them, aromatic vinyl / conjugated diene block copolymer, polyvinyl acetate, polymethyl methacrylate and saturated polyester are preferred, and aromatic vinyl / conjugated diene block copolymer and polyvinyl acetate are particularly preferred.

The aromatic vinyl / conjugated diene block copolymer is a block copolymer known per se, for example, an aromatic vinyl monomer such as styrene, chlorostyrene and vinyltoluene, and a butadiene, isoprene and the like. The conjugated diene monomer is synthesized by block copolymerization using a conventional polymerization method. Examples of such a block copolymer include a styrene / isoprene block copolymer. Such a block copolymer preferably has an aromatic vinyl monomer and a conjugated diene monomer in a molar ratio of about 50:50 to 5:95 and an average molecular weight of about 30,000 to 200,000.

The thermoplastic resin used in the present invention may be a carboxy-modified polymer as described above.
The polymer having a carboxyl group introduced therein can improve the compatibility with the unsaturated polyester resin, and can also increase the viscosity of the compound by the action of magnesium oxide when adjusting SMC and BMC.

The unsaturated polyester resin composition of the present invention comprises the above-described unsaturated polyester resin, vinyl monomer, BHT, thermoplastic resin and a compound having a polymerization inhibiting action at a temperature of 100 ° C. or more. , The storage stability is further improved, and excellent surface quality is obtained. That is, 20 to 40 parts by weight, preferably 25 to 35 parts by weight of an unsaturated polyester resin, 20 to 60 parts by weight, preferably 30 to 50 parts by weight of a vinyl monomer, 0.01 to 1.0 part by weight, Preferably, 0.08 to 0.5 parts by weight of BHT, 10 to 40 parts by weight, preferably 15 to 30 parts by weight of a thermoplastic resin are blended so as to make a total of 100 parts by weight. 0.001 to 0.1 parts by weight with respect to parts by weight,
Preferably, 0.005 to 0.05 parts by weight of a compound exhibiting a polymerization inhibiting action at a temperature of 100 ° C. or higher is incorporated. If the compounding ratio deviates from these ranges, storage stability and high surface quality deteriorate. In particular, the compounding amount of BHT is less than 0.01 part by weight, or the compound showing a polymerization inhibiting action at a temperature of 100 ° C. or more is 0.
If the amount is less than 001 parts by weight, the storage stability of the resulting unsaturated polyester resin composition is insufficient, and conversely, the amount of BHT is more than 1.0 part by weight or polymerization is inhibited at a temperature of 100 ° C. or more. The compounding amount of the compound showing the action is 0.1
If the amount is more than 10 parts by weight, the curing speed at the time of curing is slowed down, the crosslinking becomes insufficient, and the rapid curability and high surface quality are impaired.

The reaction initiator used in the present invention is tertiary-butylperoxybenzoate (TBPB), tertiary-butylperoxyoxyoctoate (TBPO),
2,5-dimethyl-2,5-di (benzoylperoxy) cyclohexane (DDBPH), tertiary amyl peroxy octoate (TAPO), tertiary
At least one is selected from organic peroxides such as butyl isopropyl carbonate (TBIPC) according to a desired curing speed. These reaction initiators are used in an amount of 0.5 to 5 parts by weight, preferably 1.0 to 3.0 parts by weight, per 100 parts by weight of the total of the unsaturated polyester resin, vinyl monomer, BHT and thermoplastic resin. I do.

In the present invention, it is desirable to use a curing accelerator together with the above-mentioned reaction initiator. Examples of the curing accelerator include organometallic compounds of cobalt, copper, and manganese, and their respective octoates, naphthenates, and acetylacetonates. These may be used alone or as a mixture. The amount of these organometallic compounds is
10 as metal for unsaturated polyester resin composition
１０００1000 ppm.

In the present invention, it is preferable to mix alkane polyol polymethacrylate and alkane polyol polyacrylate in order to improve the surface properties of the quick-curing SMC. These include, for example, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, dipropylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexane. Diol dimethacrylate, ethylene glycol diacrylate, 1,3-propanediol diacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate,
C2-I, such as 1,6-hexanediol diacrylate, trimethylolpropane dimethacrylate, glycerin dimethacrylate, pentaerythritol dimethacrylate, and trimethylolpropane diacrylate
Dimethacrylates or diacrylates of alkane polyols having 2 can be mentioned.

Further, for example, trimethylolpropane trimethacrylate, glycerin trimethacrylate, pentaerythritol trimethacrylate, glycerin triacrylate, pentaerythritol triacrylate,
Examples thereof include polyalkenyl methacrylate or polyacrylate of an alkane polyol having 3 to 12 carbon atoms, such as pentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate.

It is considered that such alkane polyol polymethacrylate and alkane polyol polyacrylate improve the elasticity of the resin component during molding, and this contributes to the hardness and smoothness of the surface of the molded article. These are used in an amount of 1 to 15 parts by weight, preferably 3 to 10 parts by weight, based on 100 parts by weight of the unsaturated polyester resin composition.

The unsaturated polyester resin composition of the present invention may contain a filler, a pigment, and a thickener, if necessary. As fillers, calcium carbonate, talc,
Examples include silica, clay, glass powder, and glass balloon. As pigments, titanium oxide, carbon black,
Red-bodied and phthalocyanine blue. Examples of the thickener include oxides and hydroxides such as magnesium and calcium.

The unsaturated polyester resin composition into which such various compounds are blended can be mixed with glass fiber (for example, having a diameter of about 8 to 20 μm and a length of 1/2 to 2 μm) using conventional means and equipment.
By impregnating the material into a molding material such as a sheet-like sheet molding compound (SMC) or a bulk-like bulk molding compound (BMC). The glass fiber is usually about 10 to 40 based on the total amount of the unsaturated polyester resin composition.
It is blended in an amount of about% by weight. The molding material of the present invention is heated and compressed in a mold (pressure 50 to 120 kgf / cm ² , temperature 110 to 1).
(80 ° C.) and cured to produce a molded product.

[0024]

EXAMPLES Sheet molding compounds (SMC) were prepared according to the compositions shown in Tables 1 and 2. Each SMC was pressurized under a predetermined condition under a pressurized flow time of 9 seconds and a pressure of 80 kgf / cm ² to produce a plate-shaped (500 × 1000 × 2 mm) molded article as shown in FIG. Comparative Examples 1 to 5 show molded products from BHT which is an essential component of the present invention or a compound which does not contain a compound exhibiting a polymerization inhibiting action at a temperature of 100 ° C. or higher. Curing characteristics and storage stability of the adjusted SMC,
Measure the surface properties and hardness of molded products manufactured from MC,
The results are shown in Tables 1 and 2.

The storage stability of the SMC is the number of days that the SMC keeps the fluidity at which the molded article shown in FIG. 1 can be formed when the SMC is stored at an ambient temperature of 23 ° C. The measurement of the surface characteristics of the molded product was performed with a three-dimensional measuring machine (Microcode FJ604; manufactured by Mitsui Corporation). First, 300 points of surface measurement (X, Y, Z) were performed on the lines 1 to 4 in FIG. 1 at a pitch of 1.0 mm, and a quintic regression curve was obtained from the Z value of each point to know the cross-sectional shape. The average deviation between the curve and the Z value at each measurement point was calculated. Fig. 1 shows the surface roughness.
Was measured by measuring line 5.

[0026]

[Table 1]

[0027]

[Table 2]

In Tables 1 and 2, A-1: an unsaturated polyester resin synthesized from propylene glycol and maleic acid. It contains 30% styrene, has a viscosity of 820 cps at 25 ° C. and an acid value of 1
6.5 was used. The numerical values in the table are parts by weight of the unsaturated polyester resin excluding styrene as a diluent. A-2: An unsaturated polyester resin synthesized from 0.9 mol of propylene glycol, 0.3 mol of dicyclopentadiene and 1.0 mol of maleic anhydride. A resin containing 35% styrene, having a viscosity at 25 ° C. of 650 cps and an acid value of 21 was used. The numerical values in the table are parts by weight of the unsaturated polyester resin excluding styrene as a diluent. B: styrene. The numerical values in the table are parts by weight containing styrene used as a diluent in the unsaturated polyester resin or the styrene / butadiene copolymer. C: BHT D-1: styrene / butadiene copolymer. This copolymer has an average molecular weight of 120,000, is composed of 15% by weight of styrene and 85% by weight of butadiene, and has 0.5% by weight of carboxyl groups. 70 parts by weight of styrene is contained with respect to 30 parts by weight of this copolymer, and the viscosity at 25 ° C. is 28%.
000 cps was used. The values in the table are parts by weight of the styrene / butadiene copolymer excluding styrene as a diluent. D-2: polyvinyl acetate E-1: t-butyl peroxyoxy octoate E-2: t-butyl peroxy benzoate E-3: 2,5-dimethyl-2,5-di (benzoyl peroxy) hexane F : Cobalt acetylacetonate G: p-benzoquinone H: trimethylolpropane trimethacrylate I: calcium carbonate J: zinc stearate K: magnesium oxide L: glass fiber (diameter 13 μm, length 1 inch) Curing properties: Curing properties of SMC (Exothermic method, 140 ° C.) 2) -1: Gelation time / Curing time (second) 2) -2: ΔT (Curing time−Geling time) Storage stability: Storage stability of SMC (days) Surface properties : Surface characteristics of molded product 4) -1: Average deviation from fifth-order regression (μ) 4) -2: Surface roughness (μ) Hardness: Hardness of molded product (Rockwell hardness, Scale)

[0029]

The unsaturated polyester resin composition of the present invention and the molding material obtained by impregnating the unsaturated polyester resin into glass fiber have high productivity because of their rapid curing properties, and also have excellent workability during curing. . Moreover, the surface of the molded product after curing has an extremely high level of surface smoothness, and is extremely useful as, for example, an automobile outer panel. In addition, because the storage stability is very good,
Even when stored for a long period of time, the curability of the unsaturated polyester resin composition and the molding material, and the surface smoothness of the molded product obtained by curing the same, do not change, and a very convenient molding material can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating a molded article according to the present invention.

[Explanation of symbols]

 1-5 ... line

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI // (C08K 5/00 5:08 5:13 5:14) (72) Inventor Hiroshi Miyashita 2-chome Yamada Nishi, Suita-shi, Osaka No. 8 A8-712 (72) Inventor Miyoshi Aoki 311-3, Rofukuji, Kashiba City, Nara Prefecture (72) Inventor Takeshi Kenta 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Takashi Ino 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (72) Inventor Yasuhiro Mishima 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Co., Ltd. (56) References JP-A-59-226053 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08J 5/04-5/10 C08L 67/06-67/07

Claims (12)

(57) [Claims] 1. An unsaturated polyester resin, a vinyl monomer, BHT (di-tert-butylhydroxytoluene), a thermoplastic resin, at least one organic peroxide as a reaction initiator, and polymerization at a temperature of 100 ° C. or more. An unsaturated polyester resin composition containing a compound exhibiting an inhibitory action. 2. An unsaturated polyester resin of 20 to 40 parts by weight, a vinyl monomer of 20 to 60 parts by weight,
1.0 part by weight of BHT (di-tert-butylhydroxytoluene) and 10 to 40 parts by weight of a thermoplastic resin,
A compound having a polymerization inhibiting effect at a temperature of 100 ° C. or more of 0.001 to 0.1 part by weight based on the total of 100 parts by weight. 2. The unsaturated polyester resin composition according to 1. 3. The unsaturated polyester resin having a molecular weight of 80
The unsaturated polyester resin composition according to claim 1, wherein the unsaturated polyester resin composition has an acid value of 0 to 4000 and an acid value of 20 to 60. 4. A compound exhibiting a polymerization inhibiting action at a temperature of 100 ° C. or more is p-benzoquinone, naphthoquinone, phenanthraquinone, p-xyloquinone, p-toluquinone, 2,6-dichloroquinone, 2,5-diphenyl-. p
-Benzoquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxy-p-benzoquinone, 2,
5. A composition according to claim 1, which is 5-diasiloxy-p-benzoquinone, hydroquinone, pt-butylcatechol, 2,5-t-butylhydroquinone, mono-t-butylhydroquinone or 2,5-di-t-amylhydroquinone.
The unsaturated polyester resin composition according to the above. 5. The unsaturated polyester resin composition according to claim 4, wherein the compound having a polymerization inhibiting effect at a temperature of 100 ° C. or higher is p-benzoquinone, hydroquinone or pt-butylcatechol. 6. The unsaturated polyester resin composition according to claim 2, wherein the compounding amount of the compound having a polymerization inhibiting effect at a temperature of 100 ° C. or more is 0.005 to 0.05 parts by weight. 7. The unsaturated polyester resin composition according to claim 1, wherein the thermoplastic resin is an aromatic vinyl / conjugated diene block copolymer, polyvinyl acetate, polymethyl methacrylate, or a saturated polyester. 8. The unsaturated polyester resin composition according to claim 1, further comprising an alkane polyol polyacrylate or an alkane polyol polymethacrylate. 9. A molding material obtained by impregnating glass fibers with the unsaturated polyester resin composition according to claim 1. 10. A molding material obtained by impregnating glass fibers with the unsaturated polyester resin composition according to claim 2. 11. A molded product obtained by curing the molding material according to claim 9. 12. A molded product obtained by curing the molding material according to claim 10.