JP3395985B2 - Low-temperature low-pressure molding material - Google Patents

Description

Detailed Description of the Invention

[0001]

[Field of Industrial Application] The molding material of the present invention is a housing material,
It is useful as a material for large-sized molded parts such as rail car parts, automobile outer panels, etc., and can be molded under conditions of lower temperature and pressure than before and has excellent storage stability in sheet or bulk form, and molded products. And a molded product thereof.

[0002]

Fiber reinforced plastics (FRP) using unsaturated polyester resin have excellent mechanical strength, heat resistance, water resistance, chemical resistance, and high productivity. For example, bathtubs and water tank panels. Widely used in wash bowls, etc. Of the FRP molding methods, compression molding using unsaturated polyester sheet molding compound (SMC) or sick molding compound (TMC), which accounts for about 30%, is highly efficient because it is mechanized and labor-saving. , Housing parts such as bathtubs and automobile parts such as spoilers are 100 times a month.
Suitable for products with a production volume of 0-5000 pieces. Further, since it is a closed system, there is no scattering of styrene or glass fiber, and the working environment is considerably better than that of conventional open-mold molding methods such as the Handlay-up (HLU) method and the spray-up (SPU) method. But,
SMC and TMC hydraulic press compression molding uses expensive molding hydraulic presses and high temperatures of 120-160 ° C, 20-15
It is made of a material such as steel that can withstand a high pressure of 0 kgf / cm ² (Japanese Patent Publication No. 60-31644), and has a structure with excellent durability, but it is expensive and has a long production period, steam, heating oil, electric heater, etc. A large amount of capital investment is required for the mold temperature control equipment. Especially in the case of housing parts and railway car parts that have recently become larger and smaller than 100 molded parts per month, the total investment will be large, considering the depreciation cost of equipment and mold per product. , SMC and TMC press molding methods are difficult to adopt, and the conventional HLU method and SP
It is produced by the U method. However, in the case of these open mold construction methods, deterioration of the work environment such as scattering of resin / glass fiber, volatilization of styrene, lack of skilled workers,
FRP with long curing time and low productivity per mold
Due to the decrease in the number of mold production engineers, there is a problem that the production time of the forming die is increased, the production cost is soaring, and it is not possible to cope with a sudden increase in the number of production.

The present inventors have solved these problems,
As a molding method that enables small-scale production of large-sized molded products to be produced efficiently in a good working environment with small capital investment, molding at low temperature and low pressure was tried, and molding tests were performed using conventional molding materials. However, the use of conventional molding materials has not yielded results that satisfy these requirements. That is, the curing temperature is changed from the conventional 120-160 ° C to 50-1.
It is necessary to use a highly reactive reaction initiator that decomposes at low temperature in order to maintain sufficient curability by lowering it to a low temperature range of 20 ° C, but with conventional molding materials, storage stability at room temperature or lower Is significantly impaired, which is a practical problem. Moreover, when a large amount of a conventionally known polymerization inhibitor such as parabenzoquinone is used, the storage stability is improved, but the curability in the low temperature range is largely impaired, and the molded product is uncured. Becomes Thus, in the conventional molding material, 50-1
It has both curability at a mold temperature in the low temperature region of 20 ° C and storage stability at room temperature, and there is no material with sufficient fluidity in the mold at the molding pressure in the low pressure region of 20 kgf / cm ² or less, and filling failure Molding defects such as voids, chips, and pinholes are generated, and a molded product having an excellent appearance and no problem in strength cannot be obtained. In the prior art, in order to enable molding at low pressure, methods such as significantly reducing the amount of fillers and thickeners to significantly reduce the viscosity of the material have been tried, but with these methods In the manufactured SMC and TMC, it is difficult to peel off the film of polyethylene, polypropylene, nylon or the like used, and workability is largely hindered, so that it cannot be used in many cases. In order to solve the above problems, it is essential to develop a molding material that is optimal for low-temperature low-pressure molding conditions.

[0004]

The problem to be solved by the present invention is to provide a molding material with curability in the low temperature region, excellent storage stability at room temperature, and excellent fluidity and filling property in the low pressure region. It is in the place to have it.

[0005]

The present invention provides an unsaturated polyester, a vinyl monomer, a stabilizer, a thermoplastic resin, an organic peroxide, a fluidity modifier, a thickener, a filler and a fiber reinforcing material. A molding material which can be molded at a pressure of about 0.1-20 kgf / cm ² and a temperature of about 50-120 ° C. and has excellent storage stability, a method for producing a molded product using the material, and the material. The present invention relates to a cured product. The above molding materials have curability at low temperature and excellent flowability at low pressure, and also show very good storage stability, and the molded products have excellent mechanical strength, heat resistance, water resistance and chemical resistance. , High surface quality (surface smoothness, paintability).

Further, the molding material of the present invention is excellent in moldability, curability and filling property under low temperature and low pressure, and is a large rail vehicle part,
It is useful as a molding material when manufacturing housing equipment parts. Further, the molding material has excellent curability at low temperatures of about 50 to 120 ° C., has very good storage stability at room temperature, and has sufficient flowability under low pressure conditions of about 20 kgf / cm ² or less. Therefore, without using a large and expensive hydraulic press and steel mold unlike the conventional molding materials, for example, resin mold, electric mold, ZAS mold, aluminum alloy mold, copper alloy mold, cast iron mold A desired molded product can be obtained by using a pair of male and female molds such as. Also, under the conditions of molding temperature and molding pressure within the above range, it is not necessary to use an expensive hydraulic press as in the past to perform mold clamping, and the molding die itself operates hydraulically or pneumatically. By arranging a plurality of cylinders, it is possible to obtain sufficient pressure to complete the mold clamping and the flow and filling of the molding material in the mold.

The unsaturated polyester used in the present invention is
It is synthesized by condensation of an α, β-olefin unsaturated dicarboxylic acid and a divalent glycol, and has been widely used in the past. In the synthesis of the unsaturated polyester, saturated dicarboxylic acid, aromatic dicarboxylic acid, or dicyclopentadiene that reacts with carboxylic acid may be used in addition to these two components. Examples of the α, β-olefinic unsaturated dicarboxylic acid include maleic acid, fumaric acid, itaconic acid, citraconic acid, and anhydrides of these dicarboxylic acids. Examples of the dicarboxylic acid used in combination with these α, β-olefinic unsaturated dicarboxylic acids include adipic acid, sebacic acid, succinic acid, phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, and het acid. Etc. Examples of the divalent glycol include alkanediol, oxaalkanediol,
A diol obtained by adding ethylene oxide or propylene oxide to bisphenol A or brominated bisphenol A is used. In addition to this, monool or trivalent triol may be used. Examples of alkanediols include ethylene glycol, 1,2-propylene glycol,
1,3-propylene glycol, 2-methyl-propane-1,3-diol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6
-Hexanediol, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A and the like. Examples of the oxaalkane diol include dioxyethylene glycol, dioxypropylene glycol, trioxyethylene glycol and the like.
Examples of monohydric or trihydric alcohols used in combination with these glycols include octyl alcohol, oleyl alcohol, trimethylolpropane and glycerin.

The synthesis of unsaturated polyester is generally carried out under heating, and the reaction proceeds while removing by-product water. In the present invention, the average molecular weight is usually 800-4000,
An acid value of 20-60 can be used. The amount used is 20-50 parts by weight, based on 100 parts by weight of the unsaturated polyester, vinyl monomer and thermoplastic resin.
It is preferably 25-35 parts by weight. These unsaturated polyesters are usually used as an unsaturated polyester resin dissolved in 30 to 150 parts by weight of a vinyl monomer described later based on 100 parts by weight of the unsaturated polyester. Examples of the vinyl monomer used in the present invention include monovinyl monomers, for example, aromatic monovinyl monomers such as styrene, parachlorostyrene, and vinyltoluene, acrylic acid, butyl acrylate, methacrylic acid, methacrylic acid methyl ester. And acrylic monovinyl monomers such as acrylonitrile. The total amount of unsaturated polyester, vinyl monomer and thermoplastic resin is 100.
20-60 parts by weight, preferably 30-5 parts by weight
0 parts by weight. These vinyl monomers are usually blended as a reactive diluent for the above-mentioned unsaturated polyester and the below-mentioned thermoplastic resin.

The stabilizer used in the present invention is BHT.
(Ditertiary butyl hydroxytoluene), TBC
(Paratertiary butyl catechol), MTBHQ
(Monotertiary butyl hydroquinone), hydroquinone monomethyl ether, BHA (butyl hydroxyanisole) and the like, which have a large effect of inhibiting polymerization at room temperature, are preferred. The amount used is 100 parts by weight in total of unsaturated polyester, vinyl monomer, and thermoplastic resin,
0.01-1.0 parts by weight, preferably 0.05-0.5
Parts by weight, more preferably 0.2-0.5 parts by weight. Among the above stabilizers, BHT is particularly preferable. B
As HT, those for industrial use or food additives can be used. BHT has a very strong scavenging action of radicals generated from a small amount of organic peroxide added as a polymerization initiator at room temperature (25 ° C.) to aging temperature (40 ° C.) of SMC and TMC. Improves storage stability remarkably. On the other hand, in the vicinity of 120-160 ° C., which is the usual SMC or TMC molding temperature, the radical scavenging action is very weak and does not cause a delay in the curing reaction, as compared with well-known polymerization inhibitors such as parabenzoquinone and hydroquinone. The molding temperature condition of the molding material of the present invention is about 5
Even in the range of 0 to 120 ° C, significant curing inhibition does not occur.
Further, it has no adverse effect on the fluidity in the mold and the surface property of the molded product. A polymerization inhibitor such as parabenzoquinone or hydroquinone may be used together for adjusting the curing rate depending on the molding conditions of SMC and TMC. When these polymerization inhibitors are used, the amount used is 100 parts by weight of the unsaturated polyester resin composition blended such that the total amount of the unsaturated polyester, the vinyl monomer, and the thermoplastic resin is 100 parts by weight. On the other hand, 0.001-0.1
Parts by weight, preferably 0.005-0.03 parts by weight. However, when these polymerization inhibitors are used alone, the storage stability at room temperature is insufficient, and when the amount used is increased by 0.1 parts by weight or more to increase the storage stability, However, curing at low temperature becomes incomplete, and the strength and surface quality of the molded product deteriorate significantly.

Examples of the thermoplastic resin used in the present invention include thermoplastic resins conventionally used as a shrinkage reducing agent for unsaturated polyester resins. Examples of such thermoplastic resins include polystyrene, polybutadiene or hydrogenated products thereof, polyisoprene or hydrogenated products thereof, aromatic vinyl / conjugated diene block copolymers or hydrogenated products thereof, styrene / vinyl acetate block copolymers. There are polymer, polyvinyl acetate, polymethylmethacrylate, etc., and saturated polyester (molecular weight 300-1
000000) and its polyurethane products, polyethers and the like. The compounding amount thereof is 5-40 parts by weight, preferably 15-30 parts by weight based on 100 parts by weight of the unsaturated polyester resin composition. The thermoplastic resin used in the present invention may be a carboxy-modified one of the above polymers. The polymer having a carboxyl group introduced therein has improved compatibility with the unsaturated polyester resin, and further improves the thickening property of the compound due to the action of magnesium oxide or magnesium hydroxide when adjusting SMC, TMC or BMC. You can also

The organic peroxide used in the present invention is tertiary butyl peroxy-2-ethylhexanoate (TB
PO), 2,5-dimethyl-2,5-di (benzoylperoxy) cyclohexane (DDBPH), tertiary amylperoxy-2-ethylhexanoate (TA)
PO), tertiary butyl isopropyl carbonate (TBIPC), tertiary hexyl peroxy-2
-Ethyl hexanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, tertiary hexyl peroxypivalate, tertiary butyl peroxypivalate, 2,5-dimethyl-2 ，
At least one selected from organic peroxides such as 5-di (2-ethylhexanoylperoxy) cyclohexane which decomposes at a low temperature of about 50 to 120 ° C. according to the desired curing rate. These are 0.5 to 5 parts by weight, preferably 100 to 100 parts by weight of the unsaturated polyester resin composition which is blended so that the total of the unsaturated polyester, the vinyl monomer and the thermoplastic resin is 100 parts by weight, 1.0-3.0
Use parts by weight. Further, an organic peroxide used in ordinary SMC which decomposes at 100 ° C. or higher, such as tertiary butyl peroxybenzoate (TBPB), may be used in combination.

In the present invention, a fluidity modifier is used for the purpose of improving the fluidity of the unsaturated polyester resin composition in the mold under low temperature and low pressure conditions. As the fluidity adjusting agent used in the present invention, a thixotropic agent and a viscosity reducing agent can be used. As the thixotropic agent, finely powdered silica (SiO ₂ ) (typically one synthesized by a high temperature gas phase method and showing hydrophilicity or hydrophobicity), an organo clay such as amine-modified montmorillonite, Vegetable oils such as hydrogenated castor oil, amide compounds of higher fatty acids such as stearic acid, lauric acid, myristic acid, palmitic acid, oleic acid and erucic acid, ethylenebisstearic acid amide, ethylenebisoleic acid amide, ethylenebiserucic acid amide Polyamide compound such as ethylene bislauric acid amide, and other inorganic compounds can be used alone or in combination. Among them, fine powder silica is preferable. The finely divided silica used in the present invention is a highly dispersible silica powder that is commercially available as a thixotropic agent such as an unsaturated polyester resin or a polyurethane resin, and usually has a bulk density of 30 to 120 g / liter and is a primary particle. Average particle size 7-40nm, specific surface area (BET) 50-500
It is in the range of m ² / g. Above all, the specific surface area is 100
The range of -300 m ² / g is preferable. Examples of the viscosity reducer include BYK-W90 manufactured by Big Chemie.
0, -W960, -W965, -W971, -W97
2, -W980, -W990, -W995, Takemoto Yushi Co., Ltd. Superdyne -V-203, -V-204, NOF Corporation Alflo series (for example, P-10, E
-10, S-10, B-10, etc.), nonion series (for example, K-230, P-210, S-220, E-
230, etc., Unistar series (eg H-47
6, H-334R, H-981R, etc.). The amount of the fluidity modifier used is 100 parts by weight of the unsaturated polyester resin composition which is blended so that the total amount of the unsaturated polyester, the vinyl monomer and the thermoplastic resin is 100 parts by weight.
0.1-5 parts by weight, preferably 0.2-
3.0 parts by weight.

The molding material of the present invention contains both a thickener and a filler, and usually an internal mold release agent. Examples of the thickener include oxides or hydroxides of magnesium, calcium, aluminum and the like, and alcoholates.
The blending amount is 0.05-2.0 parts by weight with respect to 100 parts by weight of the unsaturated polyester resin composition which is blended so that the total amount of the unsaturated polyester, the vinyl monomer and the thermoplastic resin is 100 parts by weight. , Preferably 0.2-1.0
Parts by weight, more preferably 0.3-0.8 parts by weight. As the filler, calcium carbonate, aluminum hydroxide,
Examples thereof include talc, silica, clay, glass powder and glass balloon. The blending amount thereof is 50 to 200 parts by weight, preferably 80 parts by weight based on 100 parts by weight of the unsaturated polyester resin composition which is blended so that the total amount of the unsaturated polyester, the vinyl monomer and the thermoplastic resin is 100 parts by weight. -1
80 parts by weight, more preferably 100-160 parts by weight. Examples of the internal release agent include higher fatty acids such as stearic acid, lauric acid, myristic acid, and palmitic acid, which are commonly used in SMC, and non-alkali metal salts thereof with so-called zinc, magnesium, calcium (so-called metal soap), Compounds such as silicon-based, fluorine-based and paraffin wax-based compounds can be used. The blending amount is 0.0 with respect to 100 parts by weight of the unsaturated polyester resin composition.
It is 5-20 parts by weight, preferably 0.5-10 parts by weight. Further, the unsaturated polyester resin molding material of the present invention may contain a pigment, if necessary. Examples of the pigment include titanium oxide, carbon black, red iron oxide, phthalocyanine blue and the like. The total amount of unsaturated polyester, vinyl monomer and thermoplastic resin is 10
The amount is 0.5-20 parts by weight, preferably 2-15 parts by weight, based on 100 parts by weight of the unsaturated polyester resin composition blended so as to be 0 part by weight.

Further, in the present invention, an alkane polyol polymethacrylate or an alkane polyol polyacrylate may be blended in order to improve the surface property of the molded product. 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-hexanediol dimethacrylate, ethylene glycol diacrylate, 1,3-propanediol diacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol Examples thereof include dimethacrylates or diacrylates of alkane polyols having 2 to 12 carbon atoms such as diacrylate, trimethylolpropane dimethacrylate, glycerin dimethacrylate, pentaerythritol dimethacrylate, and trimethylolpropane diacrylate. Further, for example, carbon such as trimethylolpropane trimethacrylate, glycerin trimethacrylate, pentaerythritol trimethacrylate, glycerin triacrylate, pentaerythritol triacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate. Mention may be made of polymethacrylates or polyacrylates of alkane polyols having the number 3-12.

Such alkanepolyol polymethacrylate and alkanepolyol polyacrylate accelerate the reaction rate during curing and improve the elastic modulus of the resin component, which contributes to the hardness and smoothness of the surface of the molded article. Conceivable. Further, these are 0 to 15 parts by weight, preferably 3 to 100 parts by weight of the unsaturated polyester resin composition blended so that the total amount of the unsaturated polyester, the vinyl monomer and the thermoplastic resin is 100 parts by weight. -10 parts by weight are blended. The resin composition in which such various compounding agents are blended can be used in various inorganic or organic fiber reinforcing materials, preferably glass fibers (for example, a diameter of about 8-20 μm and a length of 1 Sheet molding compound (SMC), sick molding compound (TMC), or bulk bulk molding compound (BMC). The fiber reinforcement is usually about 10-based on the total amount of the composition.
About 40% by weight is blended. The SMC and TMC of the present invention,
The pressure of BMC in the mold is about 0.1-20 kgf / cm ² , preferably about 0.5-20 kgf / cm ² , and more preferably about 2-.
10 kgf / cm ^2, most preferably 4-10kgf / cm ^2, a temperature of about 50-120 ° C., preferably about 60-100 ° C., more preferably about 70-95 ° C., and most preferably 75-9
A molded product can be produced by heating and compressing under the condition of 0 ° C. to cure. Furthermore, the SMC of the present invention,
TMC and BMC have a low temperature of about 50-120 ° C. and a temperature of about 0.
Since it can be molded at a low pressure of 1-20 kgf / cm ² , it can be molded at the same time with thermoplastic films and sheets that are easily melted or broken and foams, non-woven fabrics, cloths, papers, etc. Is. Colored or printed thermoplastic film or sheet, non-woven fabric, cloth,
By selecting and using paper etc., various colors, patterns,
It is possible to manufacture molded products with a flat or curved structure that has a pattern and has excellent functions such as weather resistance, gloss, surface smoothness, surface hardness, flame resistance, and stain resistance. Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyvinyl chloride (PVC), polyamide, polyvinyl alcohol, as materials for thermoplastic films, sheets, foams and nonwoven fabrics that can be used Polyvinylidene chloride,
Polymethylmethanolate (PMMA), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (PFEP), ethylene-tetrafluoroethylene copolymer (PETFE) , Acrylic, ABS, polyurethane, polystyrene, polyvinyl acetate and the like.

The unsaturated polyester resin molding material of the present invention comprises an unsaturated polyester, a vinyl monomer, a stabilizer, a thermoplastic resin, an organic peroxide, a fluidity modifier, a thickener and a filler as described above. As an essential component of the agent, by mixing these in a specific ratio, by impregnating the fiber reinforcement,
In particular, it has good storage stability and has excellent fluidity, filling properties and curability under molding conditions of low temperature and low pressure. That is, 20-50 parts by weight of unsaturated polyester, preferably 25-35.
20 parts by weight of vinyl monomer, preferably 3 parts by weight, preferably 3
Unsaturated polyester resin composition 100 formulated such that 0-50 parts by weight and 5-40 parts by weight of thermoplastic resin, preferably 15-30 parts by weight, total 100 parts by weight.
0.01-1.0 part by weight of the stabilizer, preferably 0.05-0.5 part by weight, more preferably 0.
2-0.5 parts by weight, organic peroxide 0.5-5 parts by weight, preferably 1.0-3.0 parts by weight, fluidity modifier 0.1-
5 parts by weight, preferably 0.2-3.0 parts by weight, thickener 0.05-2.0 parts by weight, preferably 0.2-1.0 parts by weight, more preferably 0.3-0. 8 parts by weight and 50-200 parts by weight of the filler, preferably 80-180 parts by weight, more preferably 100-160 parts by weight. If the range ratio deviates from these ranges, the storage stability may deteriorate. Further, the viscosity of the resin composition after thickening is in a viscosity range suitable for molding (500,000 to 30 million cps at 25 ° C., preferably 2 to 20 million cps.
In some cases, it may not be possible to perform molding under the low-temperature and low-pressure molding conditions as described above, deviating from s). Especially when the content of the stabilizer is 0.
When the amount is less than 01 parts by weight, the storage stability of the resin composition is insufficient, and when the amount is 1.0 parts by weight or more, the curing rate at the time of curing is slowed, and curing at a low temperature of about 50 to 120 ° C., The crosslinking reaction may be insufficient and the strength of the molded product may be insufficient.

[0017]

[Examples] Examples 1-12 and Comparative Examples 1-7 will be given below and specifically described. [Example 1] 33 parts by weight of unsaturated polyester (A-1), 14 parts by weight of unsaturated polyester (A-2), 10 parts by weight of polystyrene as a thermoplastic resin for a shrinkage reducing agent, 7 parts by weight of urethanized adipate, 36 parts by weight of styrene, tertiary amyl peroxy-2- as organic peroxide
1.5 parts by weight of ethyl hexanoate, 0.05 part by weight of ditertiary butyl hydroxytoluene as a stabilizer,
0.5 parts by weight of finely divided silica as a fluidity adjusting agent, 120 parts by weight of aluminum hydroxide as a filler, 6.0 parts by weight of zinc stearate as an internal mold release agent, and 0.4 parts by weight of magnesium oxide as a thickening agent. A blended resin composition was prepared. This resin composition is made into glass fiber (fiber length 1 inch)
64 parts by weight was impregnated using a known SMC impregnation machine, and both sides were sandwiched by polyethylene films to obtain an SMC sheet having a thickness of 2-4 mm. [Table 1] shows the measurement results of the curing characteristics of the SMC at 60 ° C and 80 ° C, the storage stability at 20 ° C and the molding fluidity at a mold temperature of 80 ° C. From this description, this SMC was at 80 ° C for 4 hours at 80
It was found to cure in 20 minutes at ° C. Also, the usable period at 20 ° C is 90 days, the upper and lower mold temperatures are 80 ° C,
Molding pressure fluidity at the conditions of 10 kgf / cm ² and 2 kgf / cm ² was good, no practical problem as a low-temperature low-pressure molding materials.

Example 2 The same as in Example 1 except that 5.0 parts by weight of trimethylolpropane trimethacrylate was added to the composition of Example 1 for the purpose of improving the surface properties and curability of the molded product. SMC was obtained by the method. The curability of this SMC was faster than that of Example 1, cured at 60 ° C. for 3.5 hours and at 80 ° C. for 17 minutes, and the surface property of the molded product was also improved. Further, usable period at 20 ° C. is 45 days, the upper and lower mold temperature of 80 ° C., fluidity was good in the conditions of molding pressure 10 kgf / cm ² and 2 kgf / cm ^2, in practical use as a low-temperature low-pressure molding materials no problem. [Example 4] To improve the storage stability, the stabilizer ditertiary butyl hydroxytoluene in the formulation of Example 1 was added to 0.1 parts by weight, and otherwise the same procedure as in Example 1 was used to prepare SMC.
Got The curability of this SMC is slower than that of Example 1,
Cured at 60 ° C. for 5 hours and 80 ° C. for 23 minutes. Also, 2
The usable period at 0 ° C. was extended to 180 days, and the storage stability was improved. Further, the fluidity at the upper and lower mold temperatures of 80 ° C. and the molding pressure of 10 kgf / cm ² and 2 kgf / cm ² is also good, and there is no practical problem as a low temperature low pressure molding material.

[Example 5] To further improve the storage stability, the amount of the stabilizer ditertiary butyl hydroxytoluene in the formulation of Example 1 was increased to 0.5 parts by weight, and otherwise the same method as in Example 1 was applied. I got SMC. The curability of this SMC was slower than that of Example 1, and was 8 hours at 60 ° C. for 8 hours.
Cured at 0 ° C. in 60 minutes. Further, the usable period at 20 ° C. was extended to 360 days, and the storage stability was further improved. Also, the upper and lower mold temperatures are 80 ° C and the molding pressure is 10 kgf.
The fluidity is also good under the conditions of / cm ² and 2 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material. [Example 6] In order to investigate the effect of the amount of the fluidity modifier on the fluidity under low temperature and low pressure molding conditions, the amount of the finely powdered silica as the fluidity modifier in the formulation of Example 1 was increased to 3.0 parts by weight. Then
An SMC was obtained in the same manner as in Example 1 except for the above. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. The usable period at 20 ° C. was also the same as 90 days. Also, the fluidity is good under conditions of the upper and lower mold temperatures of 80 ° C. and the molding pressure of 10 kgf / cm ² and 2 kgf / cm ² , which is practically no problem as a low-temperature low-pressure molding material. [Example 7] SMC was obtained in the same manner as in Example 1 except that the amount of finely powdered silica as a fluidity modifier in the formulation of Example 1 was increased to 5.0 parts by weight. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. The usable period at 20 ° C. was also the same as 90 days. Also, the fluidity is good under the conditions of the upper and lower mold temperatures of 80 ° C. and the molding pressure of 10 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material.

[Example 8] In order to investigate the effect of the amount of filler on the fluidity under low temperature and low pressure molding conditions, the amount of aluminum hydroxide as the filler in the formulation of Example 1 was reduced to 100 parts by weight, and In the same manner as in Example 1, SMC was obtained. The curability of this SMC is equivalent to that of Example 1, and 60
It was cured at 4 ° C. for 4 hours and at 80 ° C. for 20 minutes. Also, 20 ℃
The usable period in the same was 90 days. Also,
The fluidity is good under the conditions of the upper and lower mold temperatures of 80 ° C and the molding pressure of 10 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material. [Example 9] In order to investigate the effect of the amount of filler on the fluidity under low temperature and low pressure molding conditions, the amount of aluminum hydroxide as the filler in the formulation of Example 1 was increased to 150 parts by weight, and the other examples SMC was obtained in the same manner as in 1. This SMC
Has the same curability as that of Example 1, and is 8 hours at 60 ° C. for 8 hours.
Cured at 0 ° C in 20 minutes. The usable period at 20 ° C. was also the same as 90 days. Also, the upper and lower mold temperatures are 80
The fluidity is also good under the conditions of ℃ and molding pressure of 10 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material. [Example 10] In order to investigate the effect of the difference in the filler on the fluidity under the molding conditions of low temperature and low pressure, aluminum hydroxide of the filler in the formulation of Example 1 was replaced with 100 parts by weight of calcium carbonate, and In the same manner as in Example 1, SMC was obtained. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. The usable period at 20 ° C. was also the same as 90 days. Also, the upper and lower mold temperatures are 80 ° C and the molding pressure is 10 kgf / cm ²
The fluidity under these conditions is also good, and there is no practical problem as a low temperature low pressure molding material.

[Example 11] In order to investigate the influence of the difference in the filler on the fluidity under the molding conditions of low temperature and low pressure, aluminum hydroxide of the filler in the formulation of Example 1 was replaced with 180 parts by weight of calcium carbonate. Other than that, SMC was obtained by the same method as in Example 1. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. The usable period at 20 ° C. was also the same as 90 days. Also, the fluidity is good under the conditions of the upper and lower mold temperatures of 80 ° C. and the molding pressure of 10 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material. [Example 12] SMC was obtained in the same manner as in Example 1 except that 0.01 part by weight of parabenzoquinone was added as a polymerization inhibitor to the formulation of Example 1. The curability of this SMC was slower than that of Example 1, and was maintained at 60 ° C. for 4.5 hours at 80
Cured in 22 minutes at ° C. Further, the usable period at 20 ° C. is 120 days, the fluidity is good under the conditions of the upper and lower mold temperatures of 80 ° C. and the molding pressure of 10 kgf / cm ² , and there is no practical problem as a low temperature low pressure molding material.

Comparative Example 1 In order to examine the effect of the fluidity modifier on the fluidity under low temperature and low pressure molding conditions, Example 1 was used.
SMC was obtained in the same manner as in Example 1 except that the fine powdery silica as a fluidity adjusting agent was excluded from the formulation. This S
The curability and storage stability of MC were the same as in Example 1 [Table 2]. Upper and lower mold temperature is 80 ℃, molding pressure is 10kgf / cm ²
Also, the fluidity under the conditions of 20 kgf / cm ² is not suitable, and the filling of the material into the end portion, ribs and boss portion of the molded product is insufficient, and it cannot be used as a low temperature low pressure molding material. [Comparative Example 2] SMC was obtained in the same manner as in Example 1, except that the stabilizer ditertiary butyl hydroxytoluene in the formulation of Example 1 was replaced with 0.05 part by weight of the polymerization inhibitor parabenzoquinone. The curability of this SMC was slower than that of Example 1, and it was 5.5 hours at 60 ° C and 25 hours at 80 ° C.
Hardened in minutes. However, the usable period at 20 ° C. is only 15 days, which is a practical problem. Comparative Example 3 SMC was obtained by the same method as in Example 1 except that 0.12 parts by weight of parabenzoquinone was added as a polymerization inhibitor to the formulation of Example 1. The curability of this SMC was much slower than that of Example 1 and did not cure at 60 ° C.
It took 2 hours or more to cure even at 80 ° C. The usable period at 20 ° C. was 360 days. It cannot be used as a low-temperature low-pressure molding material because the fluidity and filling property under the conditions of upper and lower mold temperatures of 80 ° C. and molding pressure of 10 kgf / cm ² and 20 kgf / cm ² are not good.

Comparative Example 4 An SMC was obtained in the same manner as in Example 1 except that the amount of the stabilizer ditertiarybutylhydroxytoluene in the compound of Example 1 was increased to 1.2 parts by weight. The curability of this SMC was significantly slower than that of Example 1, it did not cure at 60 ° C., and it took 2.5 hours or more to cure at 80 ° C. Usable period at 20 ℃ is 360
It was more than a day. Upper and lower mold temperature 80 ℃, molding pressure 20kg
It cannot be used as a low-temperature low-pressure molding material because the flowability and filling property under the conditions of f / cm ² and 10 kgf / cm ² are not good, and the appearance of the molded product is extremely poor. [Comparative Example 5] SMC was obtained in the same manner as in Example 1, except that the amount of aluminum hydroxide used as the filler in the compound of Example 1 was increased to 220 parts by weight. The curability of this SMC is almost the same as in Example 1, and it is 60 ° C. for 4 hours and 80 ° C. for 20 hours.
Hardened in minutes. However, in the formulation of this comparative example, since the amount of the filler was too large, the viscosity of the resin composition after thickening was 25 ° C.
And the mold temperature was 80
° C., molding pressure fluidity of the SMC in the conditions of 20 kgf / cm ² and 10 kgf / cm ^2, filling performance is poor, it can not be used as a low-temperature low-pressure molding materials. [Comparative Example 6] SMC was obtained in the same manner as in Example 1 except that the amount of finely powdered silica as a fluidity adjusting agent in Example 1 was increased to 7.0 parts by weight. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. However, in the formulation of this comparative example, the viscosity of the resin composition after thickening was 25
50 cps or more at ℃, the upper and lower mold temperature is 80
° C., molding pressure fluidity of the SMC in the conditions of 20 kgf / cm ² and 10 kgf / cm ^2, filling performance is poor, it can not be used as a low-temperature low-pressure molding materials. [Comparative Example 7] SMC was obtained in the same manner as in Example 1 except that the amount of magnesium oxide as a thickener in the formulation of Example 1 was increased to 2.2 parts by weight. The curability of this SMC was equivalent to that of Example 1, and it was cured at 60 ° C. for 4 hours and at 80 ° C. for 20 minutes. However, in the formulation of this comparative example, since the amount of the thickener was too large, the viscosity of the resin composition after thickening was 80 million cps or more at 25 ° C., the upper and lower mold temperatures were 80 ° C., and the molding pressure was 20 kgf / The fluidity and filling property of this SMC under the conditions of cm ² and 10 kgf / cm ² are extremely poor and cannot be used as a low-temperature low-pressure molding material.

The measurement was performed by the following method-. Curing characteristics of 60 and 80 ° C by the heat generation method 60 and 80 ° C can be adjusted in the minimum unit of 0.1 ° C, and SMC with a thickness of 8mm and a size of 50mm square in the center of the mold where the upper and lower molds have the same temperature. Press with a thermocouple inserted at a position of 4 mm in thickness. At that time, a spacer having a thickness of 4 mm was installed in the mold to make the thickness constant. From the temperature-time curve obtained by this method, the gelation time (G.
T.) and curing time (CT) were calculated. Storage stability at 20 ° C. The resin composition was placed in a 600 cc ointment bottle and allowed to stand in a room at 20 ° C. to evaluate the storage stability. To determine gelation, an iron rod having a diameter of 2 mm and a length of 120 mm was vertically inserted into the resin composition, and the case where the tip of the rod did not reach the bottom of the ointment bottle was regarded as gelation. Molding fluidity at 80 ° C Using a mold of 500 mm × 1000 mm, upper and lower mold temperature: 80
℃, molding pressure: 2kgf / cm ² , 10kgf / cm ² and 20k
Press molding was performed under the molding conditions of gf / cm ² , charge rate: 36%, and material weight: 3 kg. However, the material form is S
The thickness of the molded product was 3 mm. Liquidity is determined by
The end of the molded product, the ribs and bosses attached to the molded product were visually determined whether or not the material was filled.

[0025]

[Table 1]

[0026]

[Table 2]

In Table 1 and Table 2, A-1: an unsaturated polyester synthesized from 1.0 mol of propylene glycol, 0.2 mol of dicyclopentadiene and 1.0 mol of maleic anhydride. As a 65% by weight styrene solution, the viscosity at 25 ° C. is 1200 ± 100.
cps and acid value 24 ± 3 were used. The numerical values in the table are parts by weight of unsaturated polyester excluding styrene as a diluent. A-2: An unsaturated polyester synthesized from 0.3 mol of propylene glycol, 0.7 mol of neopentyl glycol, 0.7 mol of maleic anhydride and 0.3 mol of isophthalic acid. A 55 wt% styrene solution having a viscosity at 25 ° C. of 1350 ± 100 cps and an acid value of 25 ± 3 was used. The numerical values in the table are parts by weight of unsaturated polyester excluding styrene as a diluent. B-1: Polystyrene. B-2: Urethane adipate. C: Styrene. The numerical values in the table are parts by weight containing styrene used as a diluent for unsaturated polyester, polystyrene, and urethanized adipate. D: Trimethylolpropane trimethacrylate. E: Tertiary amyl peroxy-2-ethyl hexanoate. F-1: Ditertiary butyl hydroxytoluene. F-2: Parabenzoquinone. G: Cobalt acetylacetonate. H-1: Aluminum hydroxide. H-2: calcium carbonate. I: Fine powder silica. J: Zinc stearate. K: Magnesium oxide. L: Glass fiber (diameter 13 μ, length 1 inch).

[0028]

The unsaturated polyester resin molding material of the present invention, which contains a stabilizer and a fluidity modifier, has a temperature of 50 to 120 ° C. which is not possible with conventional unsaturated polyester molding materials. Low temperature and about 0.1-20kgf / c
Sufficiently cures under low m ² pressure molding conditions, flows easily in the mold, and completely fills ribs and bosses with complicated shapes. Moreover, the obtained molded product has the same strength as conventional molding conditions. Furthermore, since the storage stability at room temperature is excellent, the curability and fluidity of the unsaturated polyester resin molding material of the present invention do not change even during long-term storage, and it is very useful in practice.

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Claims (5)

(57) [Claims] 1. An unsaturated polyester, a vinyl monomer, and
And 100 parts by weight of a resin composition containing a thermoplastic resin
Then, as a stabilizer, BHT (ditertiary butylhydroxide)
Roxytoluene) 0.01-1.0 part by weight, fluidity adjustment
A thixotropic agent 0.1-5 composed of finely divided silica as an agent
Parts by weight, 50-200 parts by weight of filler, oxidized as thickener
Magnesium or magnesium hydroxide 0.05-2 layers
Parts, and a pressure of 0.1-20 kgf / cm ² and 50-120 ° C. containing an organic peroxide and a fiber reinforcing material.
Molding material that can be molded at the temperature. ^2. A pressure of 0.5-20 kgf / cm ² and 60
The molding material according to claim 1, which is moldable at a temperature of -100 ° C. 3. A molded product obtained by curing the molding material according to claim 1 or 2. 4. An unsaturated polyester, a vinyl monomer, and
And 100 parts by weight of a resin composition containing a thermoplastic resin
Then, as a stabilizer, BHT (ditertiary butylhydroxide)
Roxytoluene) 0.01-1.0 part by weight, fluidity adjustment
A thixotropic agent 0.1-5 composed of finely divided silica as an agent
Parts by weight, 50-200 parts by weight of filler, oxidized as thickener
Magnesium or magnesium hydroxide 0.05-2 layers
0.1-20 kgf / c of an unsaturated polyester resin molding material containing a part, an organic peroxide , and a fiber reinforcement.
A method for producing an unsaturated polyester resin molded article, which comprises molding at a pressure of m ² and a temperature of 50 to 120 ° C. 5. A pressure of 0.5-20 kgf / cm ² and 60
The molding is performed at a temperature of -100 ° C.
A method for producing the described molded article.