JPH09194544A - Unsaturated polyester resin composition and production of unsaturated polyester resin molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an unsaturated polyester resin composition excellent in workability before a molding process, excellent in flowability under a low pressure, giving molded products exhibiting good appearance characteristics and hot water resistance, and useful for automotive parts, etc., by adding a prescribed amount of reinforcing fibers to a specific unsaturated polyester resin composition. SOLUTION: A composition comprising (A) 100 pts.wt. of an unsaturated polyester resin, (B) 0.1-20 pts.wt. of a compound of formula I [R is H, CH3 ; (n) is 10-36] or a compound of formula II, and (C) 50-350 pts.wt. of an inorganic fine filler such as calcium carbonate is blended with 2-50wt.% of reinforcing fibers such as glass fibers. The unsaturated polyester resin composition is compression-molded at a molding temperature of 60-120 deg.C in a molding pressure of 2-30kg/cm<2> to obtain the unsaturated polyester resin molded product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unsaturated polyester resin composition and a method for producing an unsaturated polyester resin molded article using the composition.

[0002]

2. Description of the Related Art A reinforcing fiber material such as glass fiber is impregnated with a resin composition obtained by adding a filler, a curing agent, a release agent, a pigment, a thickener, etc. to an unsaturated polyester resin to obtain a sheet or a bulk. The unsaturated polyester resin molding material formed on is a sheet molding compound (SMC),
It is called bulk molding compound (BMC) and is mainly used for compression molding and widely used for housing equipment, industrial parts, automobile parts and the like.

These molding materials are often compression-molded under heating, and conventionally the compression-molding temperature is 120 to 160.
It was molded at a high pressure of about 80 ° C. and a compression molding pressure of about 80 to 100 kg / cm ² . However, in the compression molding method, there is a problem that the cost burden becomes very large due to securing a large molding machine and expensive die investment when trying to expand the applicable products (larger size, more variety). It was Therefore, if compression molding can be performed at a lower temperature or a lower pressure, preferably at a lower temperature and a lower pressure, the cost burden can be reduced.

[0004]

However, when compression molding is carried out at a low pressure, defects such as lack of wall, cavities and pinholes are likely to occur on the surface of the molded product. Nests and pinholes not only impair the appearance of the molded product, but also adversely affect the mechanical properties and durability.

Therefore, as disclosed in JP-B-60-16471, calcium hydroxide is used as a thickening agent in order to improve the fluidity under a low pressure and eliminate the above-mentioned drawbacks. Attempts have been made to lower the viscosity of the molding material than before. However, with this method, the formation of cavities and pinholes is not sufficiently prevented, and since the molding material is sticky, the peelability of the peeling film such as the polyethylene film covering the molding material and the workability such as cutting are improved. There was a downside.

A method of adding a commercially available viscosity reducing agent (eg, Superdyne V-203: polyethylene glycol phenyl ether type compound manufactured by Takemoto Yushi Co., Ltd.) can be considered, but the viscosity after thickening is reduced. It is easy and reduces workability. Further, since the obtained molded product is likely to be discolored after being immersed in hot water, it is impossible to apply it to a product around water which is a large field of application of SMC.

An object of the present invention is an unsaturated polyester resin having excellent workability in handling, excellent fluidity even in compression molding under low pressure, good appearance characteristics and excellent hot water resistance. It is an object of the present invention to provide an unsaturated polyester resin composition and a method for producing an unsaturated polyester resin molded product, which enables a molded product to be easily obtained.

[0008]

The invention according to claim 1 relates to 100 parts by weight of an unsaturated polyester resin, 0.1 to 20 parts by weight of a compound (A) represented by the following chemical formula, and an inorganic compound. The unsaturated polyester resin composition is characterized in that reinforcing fibers are added to a composition containing 50 to 350 parts by weight of a fine filler so that the content of the reinforcing fibers is 2 to 50% by weight.

[0009]

Embedded image

In the invention described in claim 2, 0.1 to 20 parts by weight of the compound (B) represented by the following chemical formula and 50 to 350 parts by weight of the inorganic fine filler are added to 100 parts by weight of the unsaturated polyester resin. A reinforcing fiber is added to a composition containing parts to make the reinforcing fiber content 2 to 50% by weight, which is an unsaturated polyester resin composition.

[0011]

Embedded image

The invention described in claim 3 relates to a method for producing an unsaturated polyester resin molded product using the unsaturated polyester resin composition according to the invention described in claim 1 or 2, wherein the invention is defined in claim 1 or 2. The unsaturated polyester resin composition of the described invention is compression-molded at a molding pressure of ² to 30 kg / cm ² .

The invention described in claim 4 is the first invention.
Alternatively, the unsaturated polyester resin composition according to the invention described in 2 is molded at a molding temperature of 60 to 120 ° C. and a molding pressure of 2 to 30 k.
It is characterized in that compression molding is performed at g / cm ² .

The inventions according to claims 1 and 2 contain 50 to 350 parts by weight of the inorganic filler with respect to 100 parts by weight of the unsaturated polyester resin as described above, and further, the specific compound (A) or ( By including 0.1 to 20 parts by weight of B), it is common to achieve the above object.

The details of the invention described in claims 1 to 4 will be described below. The description common to the inventions described in claims 1 to 4 will be described as "the present invention". The unsaturated polyester resin composition of the present invention has the composition described in claims 1 and 2, but usually further contains an appropriate curing agent, release agent, thickener, pigment and the like. That is,
As an essential component, an unsaturated polyester resin, the compound (A) or the compound (B), an inorganic filler, and a reinforcing fiber are contained, and other optional components are usually a curing agent, a release agent, and a thickening agent. Including agents and pigments. The material which mixed these is
By covering with a release film such as a polyethylene film and aging, it is thickened to be a semi-solid molding material.

The molding material composed of the unsaturated polyester resin composition is formed into a sheet or a bulk according to the purpose. The unsaturated polyester resin used in the present invention includes an unsaturated dibasic acid, a glycol, and an unsaturated polyester obtained by polycondensing a saturated dibasic acid, if necessary, and a polymerizable monomer. And a thermoplastic resin for reducing shrinkage added by the above method.

100 parts by weight of the unsaturated polyester resin means the total amount of the unsaturated polyester polymer component, the polymerizable monomer, and the thermoplastic resin for reducing the shrinkage, which is added if necessary. It means 100 parts by weight.

As the unsaturated dibasic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid and the like are used. Examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, and bisphenol A ethylene oxide. Adducts, neopentyl glycol and the like are used.

As the saturated dibasic acid, phthalic anhydride, orthophthalic acid, isophthalic acid, terephthalic acid, adipic acid, succinic acid, tetrachlorophthalic acid, het acid and the like are used.

The acid value of the unsaturated polyester used in the present invention is usually 10 to 40 (mg-KOH / g).
Are used. It is preferably 15 to 35. When it is less than 10, the thickening does not proceed sufficiently and the compound (B) does not react during curing, so that the hot water resistance decreases. On the other hand, when it is larger than 40, the hot water resistance is lowered.

As the polymerizable monomer, styrene, dichlorostyrene, vinyltoluene, vinyl acetate, methacrylic acid, methacrylic acid ester, acrylic acid, acrylic acid ester, diallyl phthalate and the like are used, but styrene is preferably used. To be done. Usually, the amount of the polymerizable monomer contained in the unsaturated polyester resin is 20 to 60% by weight.

The thermoplastic resin for reducing the shrinkage includes, for example, polystyrene, polyvinyl acetate, polymethyl methacrylate, polyethylene, poly ε-caprolactone, saturated polyester, polyvinyl chloride, polybutadiene, polystyrene-acrylic acid copolymer. Polymers, polystyrene-polyvinyl acetate copolymers, ethylene-vinyl acetate copolymers, vinyl chloride-vinyl acetate copolymers, acrylonitrile-styrene copolymers and the like are used, and polystyrene is used in terms of price and low shrinkage. Is preferably used.

As the curing agent, tert-butyl peroxyisobutyrate, tert-butyl peroxy 2-ethylhexanoate, tert-amyl peroxy 2-ethylhexanoate, 2,4,4-trimethylpentylper Oxy-2-ethylhexanoate, tert-butylperoxypivalate, tert-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate, tert-butylperoxy 3,5,5-trimethylhexanoate,
1,1-bis (tertiary butyl peroxy) 3,
Organic peroxides such as 3,5-trimethylcyclohexane, benzoyl peroxide, methyl ethyl ketone peroxide and cumene hydroperoxide are used.

When the molding is carried out at a relatively low molding temperature of 60 to 120 ° C. as in the invention described in claim 4, the curing agent is easily decomposed at a lower temperature, for example, 2, When 4,4-trimethylpentylperoxy 2-ethylhexanoate or the like is used, and when molding is performed at a relatively high temperature, for example, 120 to 160 ° C., a curing agent that easily decomposes at a higher temperature, for example, tarsha. Libutyl peroxybenzoate and the like are used.

As the release agent, zinc stearate, calcium stearate, etc. are used. As a thickener,
Magnesium oxide, magnesium hydroxide, calcium oxide, zinc oxide and the like are used.

As the inorganic fine filler used in the present invention, calcium carbonate, aluminum hydroxide, calcium sulfate, glass powder, talc, mica and the like are used.
If the average particle size of the inorganic fine filler is too small,
The viscosity of the unsaturated polyester resin composition becomes high, the reinforcing fibers are not sufficiently impregnated, air is easily mixed into the material, and cavities are easily formed in the finally obtained molded body. On the other hand, when the average particle size of the inorganic filler is too large, the specific surface area of the inorganic filler becomes small, and it becomes difficult to obtain the effect of adding the compound (A) or the compound (B), and the fluidity of the molding material decreases. Will be done. Therefore, the average particle size of the inorganic filler is usually 0.1 to 100 μm, preferably 0.5 to
The range is 60 μm.

The mixing ratio of the inorganic fine filler is 50 to 350 parts by weight, preferably 60 to 300 parts by weight, based on 100 parts by weight of the unsaturated polyester resin. When the amount is less than 50 parts by weight, the handling property of the molding material before molding is deteriorated, and when the amount is more than 350 parts by weight, the viscosity is significantly increased, and the fluidity of the molding material at the time of molding is decreased, and it is reinforced. The impregnating property with respect to the fibers is lowered, air is easily mixed into the material, and cavities are easily formed in the obtained molded product. A plurality of types of the above-mentioned inorganic fine fillers may be used, and in that case, the total of the plurality of types of inorganic fillers is in the range of 50 to 350 parts by weight.

The reinforcing fibers used in the present invention include
Glass fibers, carbon fibers, asbestos fibers, whiskers, organic synthetic fibers, natural fibers and the like are used. Preferably, physical properties,
Glass fiber is used in terms of price. In addition to the case where a fiber having a fixed length or continuous fibers is used as it is, a mat-shaped or cloth-shaped fiber is also used. For example, in the case of glass fiber, a chopped strand obtained by cutting a strand into a predetermined length, a chopped strand mat formed by bonding a chopped strand with a binder and forming a mat shape, and the like are used. As the fixed length fiber, one having a length of 1 to 80 mm is usually used. If it is shorter than 1 mm, the reinforcing effect will be poor,
If it is longer than 80 mm, the viscosity may increase and the moldability may deteriorate. The orientation of the fibers in the unsaturated polyester resin composition is arbitrary, such as random orientation, unidirectional orientation, or X-shaped orientation.

The amount of the reinforcing fiber is mixed in the range of 2 to 50% by weight based on the whole unsaturated polyester resin composition containing the reinforcing fiber. Preferably 3-40% by weight
Range. When the amount is less than 2% by weight, the handling property of the material before molding is deteriorated, and the reinforcing effect is insufficient, and the molded product is likely to be cracked or bent. If it is more than 50% by weight, the viscosity increases and the fluidity at the time of molding deteriorates.

Compound (A) In the invention described in claim 1, the compound (A) is blended in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the unsaturated polyester resin.

As is apparent from the above chemical formula, the compound (A) is an ester having a (meth) acrylate group, and the number of carbon atoms of the hydrocarbon group bonded to the (meth) acrylate group is as described above. The range is from 10 to 36, and in particular, from the viewpoint of industrial availability, those having a hydrocarbon group having 10 to 25 carbon atoms are used. Further, as the compound (A), a plurality of kinds of compounds (A) having different carbon numbers of the above hydrocarbon groups may be mixed and used.

Specific examples of the compound (A) include lauryl acrylate, lauryl methacrylate, pentadecyl acrylate, pentadecyl methacrylate, cetyl acrylate, cetyl methacrylate, stearyl acrylate, stearyl methacrylate, behenyl acrylate and behenyl methacrylate. it can.

If the compounding ratio of the compound (A) is too low, the fluidity during molding is lowered. If the compounding ratio of the compound (A) is too large, cavities and pinholes are likely to occur on the surface of the molded product. Therefore, the compound (A) is added in an amount of 0.1 to 2 with respect to 100 parts by weight of the unsaturated polyester resin.
The amount is 0 parts by weight, preferably 0.5 to 15 parts by weight.

If the melting point of the compound (A) is too low, the handling property of the molding material before molding tends to deteriorate, and if it is too high,
Fluidity during molding is reduced. Therefore, compound (A)
The melting point of is preferably in the range of 30 ° C to 150 ° C.

Compound (B) In the invention described in claim 2, the compound (B) is contained in an amount of 0.1 to 20 relative to 100 parts by weight of the unsaturated polyester resin.
Parts by weight are blended.

As is clear from the above chemical formula, the compound (B) is an ether of a glycidyl group and a hydrocarbon group having 10 to 36 carbon atoms. From the viewpoint of industrial availability, the compound (B) has a carbon number of The compound (B) having 10 to 25 hydrocarbon groups is used. Further, as the compound (B), a plurality of kinds of compounds (B) having different carbon numbers of the above hydrocarbon groups may be mixed and used.

Specific examples of the compound (B) include lauryl glycidyl ether, decyl glycidyl ether,
Pentadecyl glycidyl ether, cetyl glycidyl ether, stearyl glycidyl ether, behenyl glycidyl ether, etc. can be mentioned.

When the compounding ratio of the compound (B) is too small,
If the flowability of the molding material during molding is reduced and too much,
Nests and pinholes are easily generated on the surface of the molded product. Therefore, the compound (B) is 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the unsaturated polyester resin.
It is blended in a proportion of 15 parts by weight.

If the melting point of the compound (B) is too low,
The handling property of the material before molding tends to be lowered, and if it is too high, the fluidity at the time of molding process is lowered. Therefore, the compound (B) preferably has a melting point in the range of 30 to 150 ° C.

Molding The unsaturated polyester resin composition of the present invention is formed into a sheet shape or a bulk shape. Sheet-shaped molding material (SM
C) is formed using a known machine. For example, on a release sheet such as a polyethylene film, using a doctor blade, apply an unsaturated polyester resin composition to a uniform thickness, sprinkle reinforcing fibers on the surface, while impregnating using a roll It can be made into a sheet. The bulk molding material (BMC) is formed by a mixer such as a kneader.

The invention according to claim 3 is the same as in claim 1 above.
A method for producing an unsaturated polyester resin molded product by compression-molding the unsaturated polyester resin composition according to the invention described in 2 under a low pressure condition.

In the invention described in claim 3, the molding pressure is 2
-30 kg / cm ² , preferably 5-20 kg /
cm ² . If the molding pressure is less than 2 kg / cm ² , the fluidity of the molding material will be reduced, and it will be difficult to obtain the desired molded product, and it will not be possible to extrude voids or reduce the voids. The surface properties and physical properties of the resulting molded article are significantly reduced. Further, when the molding pressure is higher than 30 kg / cm ² , the flow is completed before the heat is sufficiently transferred to the material in the molding die, so that the effectiveness of the unsaturated polyester resin composition of the present invention is lowered. Moreover, the above-mentioned capital investment burden cannot be reduced.

The invention described in claim 4 relates to a method for obtaining a molded product by compression-molding the unsaturated polyester resin composition according to claim 1 or 2 under conditions of low temperature and low pressure.

In the invention described in claim 4, the unsaturated polyester resin composition is charged in a required amount into a mold heated to 60 to 120 ° C. and compressed at a molding pressure of ^{2 to} 30 kg / cm ^2. Molded. Molding temperature 60-120 ℃
When the temperature is lower than 60 ° C., the fluidity of the molding material during the molding process is lowered, and the molding time is significantly lengthened. This is because the type cannot be used. For the same reason, the molding temperature is preferably 80 to 110 ° C.
Range.

A preferable example of the invention described in claim 1 As a preferable example according to the invention described in claim 1, a melting point of 30 to 100 parts by weight with respect to 100 parts by weight of the unsaturated polyester resin is used.
0.5 to 15 parts by weight of the compound (A) at 150 ° C., 60 to 300 parts by weight of calcium carbonate having an average particle size of 0.5 to 20 μm, and an average particle size of 0.5 to 30 μm as an inorganic filler.
60 to 300 parts by weight of aluminum hydroxide or 60 to 300 parts by weight of glass powder having an average particle size of 0.5 to 20 μm. In this case, a plurality of types of inorganic fillers may be used, and in that case, a plurality of types of inorganic fillers are used so that the total compounding ratio of the plurality of inorganic fillers is in the range of 60 to 300 parts by weight. .

In the unsaturated polyester resin composition having the above composition, 0.2 to 2 parts by weight of organic peroxide as a curing agent, 2 to 10 parts by weight of zinc stearate as a releasing agent, and magnesium oxide as a thickening agent. 0.2 to 3 parts by weight are mixed, and the reinforcing fibers are added to the range of 3 to 40% by weight with respect to the total amount of the resin composition using an SMC or BMC manufacturing apparatus.

Preferred Example of the Invention of Claim 2 In preparing a preferred example of the unsaturated polyester resin composition of the invention of claim 2, first, a melting point of 30 to 100 parts by weight of the unsaturated polyester resin is used. 0.5 to 15 parts by weight of compound (B) at 150 ° C., and calcium carbonate 60 having an average particle size of 0.5 to 20 μm as an inorganic filler
˜300 parts by weight, 60 to 300 parts by weight of aluminum hydroxide having an average particle size of 0.5 to 30 μm, or 60 to 300 parts by weight of glass powder having an average particle size of 0.5 to 20 μm is added. In this case, as in the case of the invention described in claim 1, plural kinds of inorganic fillers may be used, and in that case, plural kinds of inorganic fillers are mixed so that the total mixing ratio is 60 to 300 parts by weight. An inorganic filler is used.

In the above unsaturated polyester resin composition, 0.2 to 2 parts by weight of organic peroxide as a curing agent, 2 to 10 parts by weight of zinc stearate as a releasing agent, and magnesium oxide of 0.2 as a thickening agent. ˜3 parts by weight are mixed, and the reinforcing fibers are added so as to be in the range of 3 to 40% by weight based on the whole using an SMC or BMC manufacturing apparatus.

[0049]A preferred example of the invention according to claim 3 The unsaturated polyester resin molding of the invention according to claim 3.
As a preferred example of the method for producing
Preferred examples of unsaturated polyester resin composition described in 2
Using the material described above, the material is placed in a mold heated to 80 to 150 ° C.
A molding material composed of an unsaturated polyester resin composition is placed.
The mold is closed and the pressure is 5 to 20 kg / cm. ^TwoWith compression molding
I do.

A preferred example of the invention described in claim 4 In the preferred example of the invention described in claim 4, the above-mentioned claim 1
Alternatively, using the molding material cited as a preferred example of the invention described in 2, the mold is heated to 80 to 110 ° C., the molding material is placed in the mold, the mold is closed, and the pressure is 5 to 20 kg / cm.
Compress with ² .

[0051] In the invention described in the action claim 1, with respect to the unsaturated polyester resin 100 parts by weight, compound (A) 0.1 to 20 parts by weight, the inorganic fine filler is blended 50 to 350 parts by weight The reinforcing fibers have been added to the composition in the range of 2 to 50% by weight of the total. When this unsaturated polyester resin composition is compression molded, it is 2 to 30 kg / c.
Even when molded at a relatively low pressure of about m ² , the internal pressure is likely to be exerted, probably because the fluidity of the molding material is enhanced, and the air is efficiently extruded while flowing, so that there are no holes or pinholes. It is possible to obtain a molded article that does not have any shape.

This is because the compound (A) dissolves and disperses at the time of heat molding to improve the wettability of the inorganic material-resin interface,
It is considered that this is because slippage between the resin composition and the molding die was increased, thereby significantly improving the fluidity of the material during low pressure molding. Further, the above compound (A)
As described above, since it dissolves and disperses at the time of heat molding and acts to enhance the above-mentioned fluidity, the molding material before molding as in the case of using conventional calcium hydroxide as a thickener is used. Since the viscosity is not lowered, the handling property of the material before molding is not lowered.

In addition, the unsaturated polyester resin molded product obtained by using the unsaturated polyester resin composition of the invention according to claim 1 exhibits good hot water resistance. This is because the (meth) acrylate group of the compound (A) copolymerizes with the unsaturated polyester in the curing reaction process after the molding material is shaped into a mold and is trapped. It is considered that it is difficult for the compound (A) to bleed out during use.

Similarly, in the unsaturated polyester resin composition of the present invention according to claim 2, 0.1 to 20 parts by weight of the compound (B) is added to 100 parts by weight of the unsaturated polyester resin, and the inorganic fine filler is used. The reinforcing fiber is mixed with the composition containing 50 to 350 parts by weight of the composition in an amount of 2 to 50% by weight of the whole.

Even when the unsaturated polyester resin composition according to the second aspect of the present invention is used for compression molding under low pressure, the fluidity of the material at the time of compression molding may be enhanced. It efficiently extrudes and flows, and a molded product free from cavities and pinholes is obtained. This is compound (B)
However, like the compound (A), it dissolves and disperses at the time of heat molding to enhance the wettability of the inorganic material-resin interface, or to enhance the “slip” between the resin composition and the molding die. It is believed that this is because the fluidity of the molding material during low pressure molding is significantly increased.

Further, the above compound (B) is
Since it is not dissolved, like the invention according to claim 1,
It is difficult to reduce the viscosity of the material before molding, and therefore the handleability of the material before molding is not reduced.

In addition, it has been confirmed that the hot water resistance is sufficient also in the molded article obtained by using the unsaturated polyester resin composition of the invention described in claim 2. Since the compound (B) contains a glycidyl group in the molecule, the unsaturated polyester and the compound (B) are separated from each other in the curing reaction process after the unsaturated polyester resin composition is shaped into a mold shape. It is considered that this is because the compound (B) is less likely to bleed out during use of the molded product obtained by copolymerization and trapping.

In the production method according to the third aspect of the present invention, compression molding is performed using the unsaturated polyester resin composition according to the first or second aspect of the present invention. In this case, the molding pressure is 2 The range is -30 kg / cm ² .
Therefore, even when compression molding is carried out under such a low pressure condition, the unsaturated polyester resin composition according to the invention as set forth in claims 1 and 2 gives a molded article exhibiting good appearance properties and hot water resistance. Therefore, claim 1,
(2) The unsaturated polyester resin composition according to the invention described in (2) can be effectively exhibited, proper fluidity can be obtained during molding, and a molded product without cavities or pinholes can be produced. And the hot water resistance of the obtained molded article becomes sufficient.

Similarly, in the invention described in claim 4, the unsaturated polyester resin composition according to the invention described in claim 1 or 2 is used, and the molding pressure is 2 to 30 kg / c.
In addition to m ² , compression molding is performed at a relatively low molding temperature of 60 to 120 ° C. Even in the case of compression molding under such low temperature and low pressure, the unsaturated polyester resin composition according to the invention of claims 1 and 2 has improved fluidity at the time of molding and therefore has no cavities or pinholes. A molded product can be obtained stably, and the hot water resistance of the obtained molded product is also good.

Therefore, by utilizing the characteristics of the unsaturated polyester resin composition of the invention described in claim 1 or 2, compression molding can be performed at low temperature and low pressure.

[0061]

EXAMPLES First, examples of the invention described in claim 1 will be described below in comparison with comparative examples. Examples 1 to 6 and Comparative Examples 1 to 13 Unsaturated polyester composed of fumaric acid, isophthalic acid and propylene glycol (acid value 25 mg-KOH / g)
And polystyrene with 100 parts by weight of an unsaturated polyester resin (styrene content of 35
Compound (A) having a melting point shown in Table 1 with respect to (% by weight)
And a composition in which calcium carbonate (average particle diameter 2 μm) shown in Table 2, 0.8 parts by weight of magnesium oxide, 1 part by weight of organic peroxide, 0.03 part by weight of parabenzoquinone, and 5 parts by weight of zinc stearate are mixed. The product was impregnated with a 25 mm glass chopped strand, covered with a polyethylene film to give SMC, and then aged at 40 ° C. for 1 day. The glass fiber content was as shown in Table 2.

In the material 2-1 in Table 2, the compound (A) was not added. In the material 2-7, the compound (A)
Was added, and 1.8 parts by weight of calcium hydroxide was used instead of magnesium oxide as a thickener. Material 2
In -8, 100 parts by weight of silica sand (average particle size 450 μm) was added instead of calcium carbonate. In Material 2-9, stearyl alcohol having no unsaturated group in the molecule was used in place of the compound (A).

The carbon number (the number of n in each chemical formula) and the melting point of the hydrocarbon group in the compound (A) are shown in Table 1 below.

[0064]

[Table 1]

Using the above SMC, a flat plate (270 mm × 150 mm × thickness 2 mm) mold was compression-molded at the temperature and pressure shown in Table 3 by a pressing machine. At the time of charging the SMC, the SMC was placed in the corner on the short side of the flat plate mold, and the charge area ratio was about 11%.

The SMC handling property before molding was evaluated according to the following criteria. ◯: Good x: Unsaturated polyester composition easily adhered to the polyethylene film, and film peeling was difficult.

As a molding evaluation item, the fluidity of the molding material is shown by the filling area ratio of the molding material with respect to the projected area of the flat plate die, and the surface condition of the obtained molded body is observed (whether there are cavities or pinholes). showed that.

Further, the obtained molded product was immersed in hot water at 80 ° C. for one side for 300 hours, and the hot water resistance was evaluated in the following manner. Evaluation of hot water resistance: The immersion surface was measured with a color difference meter (manufactured by Tokyo Denshoku Co., Ltd., trade name: Color Analyzer TC-1800), and ΔE in L ^* , a ^* , b ^* color space by CIE was measured.
Indicated by value. The smaller ΔE indicates the better hot water resistance. Further, in order to confirm the influence of the bending characteristics depending on the glass fiber content, the bending characteristics of the molded bodies obtained in Example 3 and Comparative Example 6 were evaluated.

The flexural strength of Example 3 (glass fiber content 24%) was 12 kgf / mm ² , and the flexural strength of Comparative Example 6 (glass fiber content 1.5% by weight) was 2.5 kg.
f / mm ² .

[0070]

[Table 2]

[0071]

[Table 3]

As is clear from Tables 2 and 3, in Comparative Example 1 in which the compound (A) was not used, the filling area ratio of the molding material, which is an index of the fluidity of the molding material, was as low as 78%, It can be seen that the surface has a nest. That is,
Compared to Example 1 in which compression molding was performed under the same conditions, the compound (A) was not used, and it is considered that the above results were produced.

Even if the molding temperature was raised to 150 ° C. without using the compound (A) as in Comparative Example 2, the filling area ratio was similarly low at 83%, and the obtained molded product was There was a nest.

Further, in Comparative Example 3, since the compound 2-2 having the compounding ratio of the compound (A) of 25 parts by weight was too high, the filling area ratio was 100%. Nests were formed and the hot water resistance was reduced.

In Comparative Example 4, the calcium carbonate content in Material 2-3 was too small, which was 30 parts by weight.
The handling property of SMC before molding was not sufficient. in addition,
The filling area ratio was as low as 90%, and cavities were generated in the obtained molded body.

In Comparative Example 5, in Material 2-4, the filling area ratio was as low as 61%, probably because the glass fiber content was too high at 53% by weight, and cavities were generated in the obtained molded product.

In Comparative Example 6, the handleability of the SMC before molding was not sufficient, probably because the glass fiber content in Material 2-5 was too low as 1.5% by weight. In addition, the filling area ratio was as low as 92%, and cavities were generated in the obtained molded body.

In Comparative Example 7, in Material 2-6, the amount of calcium carbonate added was too high at 370 parts by weight, the filling area ratio was as low as 75%, and cavities were generated in the obtained molded body. .

In Comparative Example 8, the behenyl methacrylate as the compound (A) was not contained in the material 2-7, and calcium hydroxide was used in place of the magnesium oxide as the thickener. The handling of SMC was poor. In addition, the filling area ratio was as low as 88%, and cavities were generated in the obtained molded body.

Further, in Comparative Example 9, the material 2-7 was used, but despite the molding temperature being 150 ° C., the handling property of the SMC was similarly poor and the filling area ratio was 81%. And the obtained molded product had cavities.

In Comparative Example 10, the material 1-2 according to the invention described in claim 1 was used, but the molding pressure was 1 kg / cm.
Or ² and for too low, the fill area ratio of 82% and lower nests in the resulting molded article has occurred.

In Comparative Example 11, since 100 parts of silica sand having an average particle size of 450 μm was used in Material 2-8, the filling area ratio was as low as 82%. In Comparative Example 12, since the material 2-9 uses stearyl alcohol instead of the compound (A), the fluidity of the material is increased and the filling area ratio is 100%. The surface was also good, but the hot water resistance of the obtained molded product was extremely poor.

Similarly, also in Comparative Example 13, since stearyl alcohol was used, even though compression molding was carried out at a molding temperature of 90 ° C., similarly, only a molded product having low hot water resistance was obtained. .

On the other hand, in the first to sixth embodiments, the claims
Using the materials 1-1 to 1-5 which belong to the invention described in 1,
Forming temperature 90-150 ° C, molding pressure 15-20kg /
cm ^TwoSince the compression molding is performed under the conditions
Is as high as 100% and has a good surface with no cavities or pinholes.
Molded product can be obtained, and the resulting molded product has hot water
The sex was also sufficient. In addition, handling of SMC before molding
Was also good.

Next, an embodiment of the invention described in claim 2 will be described in comparison with a comparative example. Examples 7-10 and Comparative Examples 14-27 100 weight of unsaturated polyester resin which melt | dissolved the unsaturated polyester (acid value 25 mg-KOH / g) which consists of fumaric acid, an isophthalic acid, and propylene glycol in the styrene monomer. With respect to parts (styrene content 35% by weight), as compound (B), stearyl glycidyl ether (carbon number n = 18, melting point 32 ° C.) and calcium carbonate (average particle size 2 μm) in the amounts shown in Table 4, magnesium oxide A composition obtained by mixing 0.8 parts by weight, 1 part by weight of organic peroxide, 0.03 part by weight of parabenzoquinone, and 5 parts by weight of zinc stearate was impregnated into a glass chopped strand of 25 mm and covered with a polyethylene film to form an SMC.
And then aged at 40 ° C. for 1 day. The glass fiber content was as shown in Table 4.

In material 4-1 in Table 4, stearyl glycidyl ether as the compound (B) was not added. In addition, in material 4-7, stearyl glycidyl ether was not added, and magnesium oxide as a thickener was not used, but 1.8 parts by weight of calcium hydroxide was mixed instead.

In Material 4-8, 100 parts by weight of silica sand having an average particle diameter of 450 μm was used instead of calcium carbonate. In Material 4-9, stearyl alcohol having no glycidyl group in the molecule was added instead of the compound (B).

In the material 4-10, instead of the compound (B), a commercially available viscosity reducing agent, Superdyne V-203 (polyethylene glycol phenyl ether compound, manufactured by Takemoto Yushi Co., Ltd., having a glycidyl group in the molecule). I won't.)
Was added.

Using the above SMC, a press was used to perform compression molding at the temperature and pressure shown in Table 5 in the above flat plate mold. SM
The charge of C was the same as in Examples 1 to 6.

Further, evaluation of the handleability of SMC before molding,
Evaluation of the filling area ratio as an index of fluidity, observation of the surface state of the obtained molded product and evaluation of hot water resistance were performed in Examples 1 to 1.
It carried out similarly to the case of 6. The evaluation results are shown in Table 5 below.

For Example 9 and Comparative Example 19, the bending strength of the obtained molded product was measured in order to confirm the influence of the glass fiber content on the bending strength. The bending strength of Example 9 (glass fiber content 24%) is 12 k.
gf / mm ^2, bending strength of Comparative Example 19 (glass fiber content 1.5 wt%) was 2.5 kgf / mm ^2.

[0092]

[Table 4]

[0093]

[Table 5]

In Comparative Example 14, since the material 4-1 did not contain stearyl glycidyl ether as the compound (B), the filling area ratio was as low as 75%,
Nests were generated in the obtained molded body.

Further, in Comparative Example 15, similarly, since stearyl glycidyl ether was not used, the molding temperature was set to 1
Even at 50 ° C., the filling area ratio was as low as 78%, and cavities were generated in the obtained molded body.

Further, in Comparative Example 16, in Material 4-2, the composition ratio of stearyl glycidyl ether was too high at 25 parts by weight, probably because the obtained molded product had cavities and the hot water resistance was low. It was

In Comparative Example 17, the handleability of the SMC before molding was low, probably because the blending ratio of calcium carbonate was 30% by weight in the material 4-3, which was too low. In addition, the filling area ratio was as low as 92%, and cavities were generated in the obtained molded body.

In Comparative Example 18, in the material 4-4, the glass fiber content was too high at 53% by weight, the filling area ratio was extremely low at 65%, and cavities were formed in the obtained molded product. It was

In Comparative Example 19, in Material 4-5, the glass fiber content was too low at 1.5% by weight, the SMC handling property before molding was low, the filling area ratio was low at 94%, and Nests were generated in the formed body.

In Comparative Example 20, the filling area ratio was considerably low at 78% in Material 4-6, probably because the blending ratio of calcium carbonate was too large at 370 parts by weight, and cavities were formed in the obtained molded body. It was

In Comparative Example 21, the stearyl glycidyl ether was not used in the material 4-7, and 1.8 parts by weight of the above calcium hydroxide was used instead of magnesium oxide as the thickener. S before molding
The handling of the MC was poor. In addition, the filling area ratio is 88
%, Which was low, and there were cavities in the obtained molded product.

Also in Comparative Example 22, the material 4-7 was used, and the molding temperature was 150 ° C.
Was poor in handleability, the filling area ratio was as low as 81%, and cavities were formed in the molded body.

In Comparative Example 23, the material 3-2 belonging to the invention of claim 2 was used, but the molding pressure was 1 kg /
The filling area ratio was as low as 78%, probably because it was too low as cm ² .
Nests were formed in the obtained molded body.

In Comparative Example 24, silica sand 1 having an excessively large average particle size was used in place of calcium carbonate in Material 4-8.
The packing area ratio is 80, probably because 00 parts by weight was used.
% Was low.

In Comparative Example 25, since the stearyl alcohol having no glycidyl group was used in the material 4-9, the fluidity was improved to some extent and the filling area ratio was 100.
%, And no cavities were generated on the surface, but the hot water resistance of the obtained molded product was remarkably reduced.

Also in Comparative Example 26, since the material 4-9 was used, even if the molding temperature was lowered to 90 ° C., the hot water resistance of the obtained molded product was still considerably low. In Comparative Example 27, in the material 4-10, probably because a commercially available viscosity reducing agent was used, the SMC before handling was low in handleability, and the filling area ratio was low at 95%, and a cavity was generated in the obtained molded body. However, the hot water resistance of the obtained molded product was significantly deteriorated.

On the other hand, materials 3-1 to 3-3 within the scope of the invention of claim 2 are used, and the molding temperature is 90 to 150 ° C. and the molding pressure is 10 to 15 kg / cm.
^In Examples 7 to 10 in which SMC was ² , the handling property before molding of SMC was good, and the filling area ratio was 100% even when compression molding was performed under the low pressure conditions as described above, There were no cavities or pinholes in the molded product. In addition, hot water resistance was also good.

[0108]

As described above, in the unsaturated polyester resin composition according to the first aspect of the present invention, the compound (A) and the inorganic fine filler are contained in the above specified amount per 100 parts by weight of the unsaturated polyester resin. The reinforcing fibers are blended in a ratio of 2 to 50% by weight based on the total weight. In this case, since the compound (A) does not dissolve at room temperature before molding, the unsaturated polyester resin composition according to the invention of claim 1 has sufficient viscosity before molding,
The handleability before molding is not impaired.

Further, during heat molding, the above compound (A) is dissolved and dispersed, and the viscosity of the molding material is effectively reduced. Further, the wettability between the inorganic material-resin interface is enhanced, or the “slip” between the composition and the molding die is enhanced, whereby the fluidity of the molding material is sufficiently enhanced even under low pressure conditions. To be Therefore, even when molding is performed at a low pressure, the air flows while extruding the air efficiently, so that it is possible to easily obtain a molded product having excellent appearance without cavities or pinholes.

Further, since the compound (A) contains an unsaturated group in the molecule, it forms a bond with the unsaturated polyester during the curing reaction process and is trapped. Therefore,
Since the compound (A) is unlikely to bleed out during use, the hot water resistance of the obtained molded article is also enhanced.

Similarly, in the unsaturated polyester resin composition according to the second aspect of the present invention, the amount of the compound (B) is 0.1 to 2 relative to 100 parts by weight of the unsaturated polyester resin.
0 part by weight, the inorganic fine filler is blended in the above-mentioned specific proportion, and the reinforcing fiber is blended in the proportion of 2 to 50% by weight of the whole. Therefore, since the compound (B) is not dissolved before molding, the molding material has a sufficient viscosity, and the handling property of the molding material before molding is not easily impaired.

In addition, at the time of heat molding, the compound (B) is dissolved, the viscosity of the molding material is significantly lowered, the wettability of the interface between the inorganic material and the resin is enhanced, and the composition and the molding die are separated from each other. The "slip" between them is enhanced, and the fluidity of the molding material is sufficiently large even when low-pressure molding is performed. Therefore, even in the case of low-pressure molding, since the molding material flows while efficiently extruding air, it is possible to easily obtain a molded product having an excellent appearance without cavities or pinholes.

In addition, in the compound (B), the glycidyl group is bonded to the unsaturated polyester in the curing reaction process, and the compound (B) is trapped. Therefore, since the compound (B) is unlikely to bleed out while the molded product is used, the hot water resistance of the molded product is also enhanced.

In the invention described in claim 3, the above-mentioned claim 1
Alternatively, since the unsaturated polyester resin composition according to the invention described in 2 is used, the molding pressure is 2 to 30 kg / cm.
Despite molding with a relatively low pressure of ² , it is possible to stably obtain a molded body in which cavities and pinholes are unlikely to occur and which has excellent hot water resistance. Moreover, the pressure is 2 to 30 kg.
Since it can be as low as / cm ² , the mold investment cost in the molding machine can be reduced, and it becomes possible to inexpensively supply a molded product having good appearance properties and hot water resistance.

In the invention described in claim 4, since the unsaturated polyester resin composition according to the invention described in claim 1 or 2 is used for molding, the molding temperature is 60 to 1
Relatively low at 20 ℃ and molding pressure of 2-30kg / c
Despite being as low as m ² , it is possible to obtain a molded body that is less likely to have cavities and pinholes and has excellent hot water resistance. Therefore, it is possible to further reduce the mold investment cost and the like, and it is possible to inexpensively supply a molded product having good appearance characteristics and hot water resistance.

Claims (4)

[Claims] 1. A compound (A) represented by the following chemical formula is added to 0.1 part by weight with respect to 100 parts by weight of an unsaturated polyester resin.
The unsaturated polyester resin composition is characterized by adding reinforcing fibers to a composition containing 20 to 20 parts by weight and 50 to 350 parts by weight of an inorganic fine filler so that the content of the reinforcing fibers is 2 to 50% by weight. Embedded image 2. A compound (B) represented by the following chemical formula is added to 0.1 part by weight with respect to 100 parts by weight of an unsaturated polyester resin.
To 20 parts by weight and 50 to 350 parts by weight of the inorganic fine filler, a reinforcing fiber is added to the composition to adjust the reinforcing fiber content to 2
Unsaturated polyester resin composition, characterized in that the content is up to 50% by weight. Embedded image 3. A method for producing an unsaturated polyester resin molding, which comprises compression molding the unsaturated polyester resin composition according to claim 1 or 2 at a molding pressure of ² to 30 kg / cm ² . 4. An unsaturated polyester resin molded article, characterized in that the unsaturated polyester resin composition according to claim 1 or 2 is compression molded at a molding temperature of 60 to 120 ° C. and a molding pressure of ² to 30 kg / cm ^2. Manufacturing method.