JPH0359102B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester resin composition that has good surface gloss and can provide molded articles with excellent mechanical properties such as impact resistance and rigidity. Due to its excellent properties, polyethylene terephthalate is used in a wide range of fields such as electrical and electronic equipment parts and automobile parts. Among these, polyethylene terephthalate is used in fibrous materials such as glass fiber in applications that require particularly high rigidity and high heat distortion temperature. Many methods are used to modify the material by adding reinforcing materials or granular reinforcing materials such as talc. However, molded products obtained from polyethylene terephthalate blended with reinforcing agents in this manner have extremely poor appearance, including surface gloss, and there is a strong desire to improve this drawback. For this reason, attempts have been made to improve the appearance of molded products by adding various third additives, but even if the surface gloss can be improved to some extent, on the other hand, impact resistance may have to be sacrificed. There are problems, and the current situation is that a fully satisfactory method has not yet been obtained. Therefore, the present inventors conducted intensive studies with the aim of obtaining a polyester resin composition that has good surface gloss and can provide molded products with excellent mechanical properties such as impact resistance and rigidity. On the other hand, the present inventors have discovered that the above object can be achieved by blending a reinforcing material, a specific olefin copolymer, and a specific polyfunctional compound in specific amounts. That is, the present invention uses (A) 1 to 150 parts by weight of a fibrous and/or granular reinforcing material, (B) an α-olefin having 2 to 4 carbon atoms, and the following general formula () to 100 parts by weight of polyethylene terephthalate. 1 to 100 parts by weight of an olefinic copolymer consisting of α,β-unsaturated acid glycidyl ester of (In the formula, R is a hydrogen atom or a lower alkyl group.) and (C) epoxysilane, diepoxy compound, epoxidized polybutadiene, triglycidyl isocyanurate, diisocyanate, polyurethane with isocyanate at both terminals, and tetracarboxylic dianhydride. The object of the present invention is to provide a polyester resin composition for molding, which contains 0.001 to 10 parts by weight of at least one polyfunctional compound selected from the group. The polyethylene terephthalate used in the present invention is a polyester obtained by a condensation reaction of a dicarboxylic acid component in which at least 40 mol% of the dicarboxylic acid component is terephthalic acid and an ethylene glycol component. , C2-20 aliphatic dicarboxylic acids such as sebacic acid, adipic acid, dodecanedioic acid, isophthalic acid, orthophthalic acid, naphthalene dicarboxylic acid, diphenyl-4,
4'-dicarboxylic acid, diphenylethane-4,4'-
Examples include aromatic dicarboxylic acids such as dicarboxylic acid and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, alone or in mixtures. In addition, the above polyethylene terephthalate is
Relative viscosity of 0.5% orthochlorophenol solution measured at 25°C is 1.2-2.0, especially 1.3-1.8
If it is less than 1.2, sufficient mechanical properties cannot be obtained, and if it exceeds 2.0, a molded product with good surface gloss cannot be obtained, so both are undesirable. The reinforcing material used in the present invention is fibrous, granular, or a mixture of both. Examples of fibrous reinforcing materials include inorganic fibers such as glass fibers, glass fibers, alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, metal fibers (such as stainless steel fibers), and carbon fibers. In addition, granular reinforcement materials include wollastenite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, silicates such as alumina silicate, alumina, silicon oxide, magnesium oxide, zirconium oxide,
Metal oxides such as titanium oxide, calcium carbonate,
Examples include carbonates such as magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, glass beads, boron nitride, silicon carbide, Saroyan, etc., and these may be hollow (for example, hollow glass fibers, glass micro balloons, white balloons, carbon balloons, etc.).
The above reinforcing materials may be used after being pretreated with coupling agents such as silane and titanium, if necessary. The amount of the reinforcing material added is 1 to 150 parts by weight per 100 parts by weight of polyethylene terephthalate,
Preferably it is 3 to 80 parts by weight. If the amount added is less than 1 part by weight, sufficient mechanical strength cannot be obtained, and if it exceeds 150 parts by weight, the surface gloss tends to be impaired, making it difficult to achieve the object of the present invention. The α-olefin in the olefin copolymer comprising α-olefin and glycidyl ester of an α,β-unsaturated acid used in the present invention is ethylene, propylene, butene-1, etc., and ethylene is preferably used. In addition, glycidyl ester of α,β-unsaturated acid has the general formula (In the formula, R is a hydrogen atom or a lower alkyl group.) Specifically, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, etc., with glycidyl methacrylate being preferably used. . The amount of the copolymer of glycidyl ester of α,β-unsaturated acid is suitably in the range of 1 to 50% by weight. In addition, unsaturated monomers that can be copolymerized with the above copolymers at 40% by weight or less, such as vinyl ethers, vinyl ester acids such as vinyl acetate and vinyl propionate, acrylic acids and methacrylic acids such as methyl, ethyl, and propyl. One or more types of acid esters, acrylonitrile, styrene, carbon monoxide, etc. may be copolymerized. The amount of the olefin copolymer added is 1 to 100 parts by weight, preferably 3 to 50 parts by weight, per 100 parts by weight of polyethylene terephthalate. If the amount added is less than 1 part by weight, the surface gloss will not be improved sufficiently, and if it exceeds 100 parts by weight, the surface gloss will tend to be impaired, making it difficult to achieve the object of the present invention. Next, examples of the polyfunctional compound used in the present invention include epoxysilane, diepoxy compound, epoxidized polybutadiene, triglycidyl isocyanurate, diisocyanate, polyurethane with isocyanate at both terminals, and tetracarboxylic dianhydride. Specifically, epoxysilanes such as γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, bisphenol A type epoxy compounds, bisphenol Alicyclic compound epoxy compounds such as phenol F type epoxy compounds, resorcinol type epoxy compounds, tetrahydroxyphenylmethane type epoxy compounds, novolak type epoxy compounds, vinylcyclohexene dioxide, dicyclopentadiene oxide, glycidyl ethers, epoxidized polybutadiene, Polyepoxy compounds such as triglycidyl isocyanurate, 2,4-
Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, metaxylylene diisocyanate, 1,5-naphthalene diisocyanate, polyphenyl isocyanate, and derivatives of the above isocyanates (polymer urethane, uretidione diisocyanate) isocyanate compounds such as higher-order oligomers, cyanurate polymers), pyromellitic residual anhydride, naphthalene tetracarboxylic dianhydride, and general formula (However, in the formula, X represents -O-, -SO ₂ -, -CO- or a divalent hydrocarbon.) For example, bis(3,4-dicarboxyphenyl)alkane dianhydride Examples include carboxylic acid anhydrides such as Among these polyfunctional compounds, preferred ones have the general formula (However, n is a number from 0 to 20.) It is a bisphenol A type epoxy compound represented by: The above polyfunctional compounds may be one or two types.
The total amount added is 0.001 parts by weight per 100 parts by weight of polyethylene terephthalate.
It is used in a range of 10 parts by weight, preferably 0.005 to 5 parts by weight. If the amount added is less than 0.001 part by weight, the surface gloss will not be improved sufficiently, and if it exceeds 10 parts by weight, the surface gloss will tend to be impaired, making it difficult to achieve the object of the present invention. For the composition of the present invention, antioxidants and heat stabilizers (including, for example, hindered phenols, hydroquinones, thioethers, phosphites, substituted products thereof, and combinations thereof), ultraviolet rays, etc. absorbents (e.g. various resorcinols, salicylates, benzotriazoles, benzophenones, etc.), lubricants and mold release agents (e.g. stearic acid and its salts, montanic acid and its salts, esters, half esters, stearyl alcohol, stearamide, etc.);
Colorants, including dyes (e.g. nitrosine) and pigments (e.g. cadmium sulfide, phthalocyanine, carbon black, etc.), flame retardants (e.g. decabromodiphenyl ether, halogens such as brominated polycarbonate, melamine or cyanuric acid, phosphorus) It is possible to add one or more conventional additives such as flame retardant aids (e.g., antimony oxide), antistatic agents (e.g., sodium dodecylbenzenesulfonate, polyalkylene glycol, etc.), and crystallization promoters. can. In addition, small amounts of other thermoplastic resins (e.g. polyethylene, polypropylene, acrylic resins, fluorine resins, polyamides, polyacetals, polycarbonates, polysulfones, polyphenylene oxides, etc.), thermosetting resins (e.g. phenolic resins, melamine resins, polyester resins) , silicone resins, epoxy resins, etc.), soft thermoplastic resins (e.g. ethylene/vinyl acetate copolymers, polyester elastomers,
(ethylene/propylene terpolymer, etc.) may also be added, and these resins may be used not only alone but in combination of two or more. Although the method for producing the composition of the present invention is not particularly limited, a preferred method is to melt-knead polyethylene terephthalate, an olefin copolymer, a polyfunctional compound, and a reinforcing material in an extruder, and then cut the mixture into pellets. Can be mentioned. Furthermore, as a method for adding a polyfunctional compound, a method in which glass fibers are pretreated and added is also often used. The resin composition of the present invention can be easily molded by conventional methods such as injection molding and extrusion molding, and the resulting molded product exhibits excellent properties. The present invention will be explained below with reference to Examples. <Example> Examples 1 to 6, Comparative Examples 1 to 6 Polyethylene terephthalate with a relative viscosity of 1.34
To 100 parts by weight, ethylene/glycidyl methacrylate (90/10 weight ratio) copolymer, γ-glycidoxypropylmethoxysilane and glass fiber (3 mm long chopped strand) were dried in the proportions shown in Table 1. The mixture was blended and melt mixed into pellets using a screw extruder set at 280°C. Next, the obtained pellets were molded using an injection molding machine set at 280°C, with the mold temperature set in the range of 70°C to 120°C, and molded into 80 mm x 80 mm x 2 mm square plates and ASTM
A 1/2 inch wide Izot impact test piece was prepared in accordance with the D256 standard. Using these test pieces, the appearance (directional gloss, color tone) of the molded products was observed, and the Izot impact value was measured, and the results shown in Table 1 were obtained. For comparison, a composition obtained by appropriately removing additives other than polyethylene terephthalate and glass fiber from the above composition was similarly evaluated. The use of ethylene/glycidyl methacrylate copolymer allows molded products with good appearance even at mold temperatures of 70°C, and surface gloss is further increased by raising the mold temperature to 120°C. I understand that. Furthermore, it is found that such a copolymer increases the Izot impact strength, and that γ-glycidoxypropylmethoxysilane is essential for imparting surface gloss in the coexistence of a modified polyolefin copolymer.

【table】

[Table] Examples 7 to 15, Comparative Examples 7 to 16 Polyethylene terephthalate with a relative viscosity of 1.39
For 100 parts by weight, 20 parts by weight of ethylene/glycidyl methacrylate/vinyl acetate (82/12/6 polymerization ratio) copolymer and 40 parts by weight of glass fiber (3 mm long chopped strand) as an olefin copolymer. After dry blending 20 parts by weight of wollastenite and the types and amounts of polyfunctional compounds shown in Table 2, melt mixing, injection molding and property evaluation were carried out in the same manner as in Example 1. The results obtained are shown in Table 2. As is clear from the results in Table 2, the composition of the present invention in which both the olefinic copolymer and the polyfunctional compound are used together has a synergistic improvement in impact strength and a good surface gloss of the molded article. Regarding the surface gloss of the molded product, the difference from the comparative example becomes large, especially when the mold temperature becomes low, and it is clear that the curing of the composition of the present invention is excellent.

【table】

【table】

Claims (1)

[Claims] 1. (A) fibrous and/or granular reinforcing material 1 to 100 parts by weight of polyethylene terephthalate.
150 parts by weight, (B) Olefin copolymer 1 to 100 consisting of α-olefin having 2 to 4 carbon atoms and α,β-unsaturated acid glycidyl ester of the following general formula ()
Weight part (In the formula, R is a hydrogen atom or a lower alkyl group.) and (C) epoxysilane, diepoxy compound, epoxidized polybutadiene, triglycidyl isocyanurate, diisocyanate, polyurethane with isocyanate at both terminals, and tetracarboxylic dianhydride. A molding polyester resin composition comprising 0.001 to 10 parts by weight of at least one polyfunctional compound selected from the group.