JPH0433816B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aromatic polyester resin composition that can provide molded articles with excellent mechanical properties, including heat distortion temperature and impact resistance. Aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate are used in a wide range of fields such as electrical and electronic equipment parts and automobile parts due to their excellent properties. It has the disadvantage of a low deformation temperature (as defined in ASTM D-648-72). Attempts have been made to improve the heat deformation temperature of aromatic polyester using modifiers other than reinforcing agents, and among them, styrene, α, and The method of blending a copolymer of β-unsaturated cyclic imide as a modifier certainly increases the heat distortion temperature of polyethylene terephthalate. However, the compositions obtained by these methods have very low mechanical properties, typified by impact resistance, and are difficult to put into practical use. As a result of intensive studies to solve the above problem, the inventors of the present invention found that by adding a polyvalent epoxy compound to a specific aromatic polyester along with a specific vinyl copolymer, the heat distortion temperature can be reduced. We discovered that it is possible to obtain a composition with excellent mechanical properties, including high impact resistance.
We have arrived at the present invention. That is, the present invention uses (A) an aromatic vinyl monomer and an α,β-unsaturated cyclic maleimide based on 100 parts by weight of an aromatic polyester selected from polybutylene terephtate and polycyclohexane dimethylene terephthalate. The present invention relates to a resin composition containing 5 to 80 parts by weight of a vinyl copolymer consisting of a compound and 0.5 to 100 parts by weight of (B) a polyvalent epoxy compound. The aromatic polyester used in the present invention is one or more selected from polybutylene terephthalate and polycyclohexane dimethylene terephthalate. Further, these aromatic polyesters preferably have a relative viscosity in the range of 1.2 to 1.8 when a 0.5% orthochlorophenol solution is measured at 25°C. Next, the aromatic vinyl monomer in the vinyl polymer consisting of (A) aromatic vinyl monomer and β-unsaturated cyclic imide compound used in the present invention is represented by the following general formula (). Among these, styrene derivatives in which Ar is a benzene ring are preferred. [However, R ¹ to ^{R 3} in the formula are each selected from a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and a halogen; Ar is an aromatic group having 6 to 24 carbon atoms;
is a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, halogen, -CN, -
NO ₂ , -NH ₂ , -SO ₃ M (M is an alkali or alkali metal), n is an integer of 1 to 5] Specific examples of aromatic vinyl monomers include styrene, α-methylstyrene, β-methylstyrene,
α,β-dimethylstyrene, P-methylstyrene, m-methylstyrene, o-methylstyrene,
2,5-dimethylstyrene, 3,5-dimethylstyrene, 2,4,6-trimethylstyrene, P-
Ethylstyrene, P-isopropylstyrene, P
-tert-butylstyrene, P-chlorostyrene,
Examples include 2,5-dichlorostyrene, P-bromomethylstyrene, P-fluorostyrene, P-methoxystyrene, P-acetoxystyrene, -cyanostyrene, and sodium P-vinylbenzenesulfonate, especially styrene and α-
Methylstyrene can be preferably used. Further, the α,β-unsaturated cyclic imide compound is a compound represented by the following general formula () or (). (However, R ⁴ , R ⁵ , and R ⁷ in the formula are each a hydrogen atom,
It is selected from a hydrocarbon group having 1 to 10 carbon atoms, a carboxyalkyl group, a carboxyalkenyl group, and a halogen, and R ⁸ is selected from a hydrocarbon group having 1 to 10 carbon atoms, and a carboxy-substituted hydrocarbon group. and R ⁶ and R ⁹ are hydrogen, carbon number 1 to
20 substituted or unsubstituted alkyl groups, cycloalkyl groups, aryl groups, etc. Specific examples of α,β-unsaturated cyclic imide compounds include maleimide, methylmaleimide, dimethylmaleimide, itacoimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-t-butyl Maleimide, N-laurylmaleimide, N-phenylmaleimide, N-(P-chlorophenyl)maleimide, N-(P-bromophenyl)maleimide, N-(P-tolyl)maleimide, N-(P-
Examples include anisyl)maleimide, N-(P-ethylphenyl)maleimide, N-(4'-diphenyl)maleimide, N-(1-naphthyl)maleimide, and especially maleimide, N-methylmaleimide, and N-phenylmaleimide. It can be used preferably. The vinyl copolymer (A) consisting of an aromatic vinyl monomer and an α,β-unsaturated cyclic imide compound can be produced in the presence of rubber. Examples of the rubber in this case include polybutadiene, styrene/butadiene copolymer, butadiene/acrylonitrile copolymer, isobutylene/isoprene copolymer, polyisoprene, polychloroprene, and ethylene/propylene/diene terpolymer. The vinyl copolymer (A) is produced by reacting a vinyl copolymer consisting of an aromatic vinyl monomer and an α,β-unsaturated acid anhydride with a primary amine in an organic solution. You can even get it. The copolymerization composition of the vinyl copolymer (A) is 5 to 40% by weight of α,β-unsaturated cyclic imide compound, especially 5 to 25% by weight.
A range by weight of from 95 to 60% by weight of aromatic vinyl monomer, especially from 95 to 75% by weight and from 0 to 30% by weight of rubber is suitable. Examples of preferred vinyl copolymers (A) include styrene/maleimide copolymers, styrene/N-phenylmaleimide copolymers, and polybutadiene-containing products thereof. The vinyl copolymer (A) used in the present invention needs to be contained in an amount of 5 to 80 parts by weight, preferably 10 to 80 parts by weight, per 100 parts by weight of the aromatic polyester. If the amount added is less than 5 parts by weight, the heat distortion temperature will not be improved sufficiently, and if it exceeds 80 parts by weight, it will tend to impair the mechanical properties of the aromatic polyester, making it difficult to achieve the purpose of the present invention. Become. Furthermore, the polyvalent epoxy compound (B) used in the present invention is a compound having at least two epoxy groups in the molecule, for example, a bisphenol type epoxy compound obtained by reacting bisphenol and epichlorohydrin in various ratios. compounds, novolac type epoxy compounds obtained from novolac resin and epichlorohydrin, polyglycidyl esters obtained from polycarboxylic acids and epichlorohydrin, etc., alicyclic compound type epoxy compounds obtained from alicyclic compounds (e.g. dicyclopentadiene), alcoholic Aliphatic compounds with hydroxyl groups (e.g., butanediol, glycerin, etc.)
and glycidyl ethers obtained from epichlorohydrin, epoxidized polybutadiene, and unsaturated monomers having epoxy groups (e.g., unsaturated glycidyl esters, unsaturated glycidyl ethers, etc.) and other unsaturated monomers (e.g., α-olefin, Examples include epoxy group-containing copolymers consisting of vinyl esters, etc.). Suitable examples of these epoxy compounds include polyglycidyl esters represented by the following general formula (), bisphenol type epoxy compounds represented by the following general formula (), and α-olefin/α,β-unsaturated acid glycidyl ester copolymer. Examples include merging. (However, in the formula, ^R10 represents an alkylene group having 4 to 40 carbon atoms, a phenylene group, a partially hydrogenated phenylene group, or a cyclohexylene group) (However, in the formula, m is a number from 0 to 20.) Specific examples of the polyvalent epoxy compound (B) include hexahydrophthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, phthalic acid diglycidyl ester, and terephthalic acid. Examples include diglycidyl ester, ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, ethylene/carbon monoxide/glycidyl methacrylate copolymer, and ethylene/glycidyl acrylate copolymer. Among them, ethylene/glycidyl methacrylate copolymer is most preferred. Polyvalent epoxy compound (B) used in the present invention
The amount added is 0.5 to 100 parts by weight, preferably 2 to 50 parts by weight, per 100 parts by weight of the aromatic polyester. If the amount added is less than 0.5 parts by weight, the impact resistance will not be improved sufficiently, and if it is more than 100 parts by weight, it will tend to impair the mechanical properties of the aromatic polyester. Become. Incidentally, when a compound that promotes the reaction between the epoxy compound and the carboxylic acid is further added to the composition of the present invention, it is possible to obtain the effect that the impact resistance can be further improved. These compounds include tertiary amines such as triphenylamine and 2,4,6-tris(dimethylaminomethyl)phenol, phosphorous esters such as triphenylphosphite and triisodecylphosphite, and triphenylallylphosphonium bromide. phosphonium compounds such as, tertiary phosphine such as triphenylphosphine, metal carboxylates such as lithium stearate and calcium stearate, metal sulfonates such as sodium dodecylbenzenesulfonate and sodium 3,5-dicarbomethoxybenzenesulfonate. Salts, sulfate ester salts such as sodium lauryl sulfate, and the like are included, and it is preferable to add 0.001 to 5 parts by weight per 100 parts by weight of the aromatic polyester. The composition of the present invention may contain conventional additives such as antioxidants, ultraviolet absorbers, heat stabilizers, lubricants, mold release agents, colorants including dyes and pigments, fibers, etc., to the extent that the object of the present invention is not impaired. solid and granular fillers and reinforcements (e.g. glass fibers, glass beads, carbon fibers, calcium carbonate, magnesium carbonate, barium sulfate, finely divided silicic acid, wollastenite, talc, clay, mica, sericite, zeolites,
(bennite, dolomite, kaolin, etc.), nucleating agents, flame retardants, other thermoplastic resins, etc. These additives may be added singly or in combination of two or more. Among these various additives, addition of crystal nucleating agents typified by inorganic oxides such as talc and various metal soaps such as sodium stearate and barium stearate is particularly important in the case of polyethylene terephthalate. In addition, the use of plasticizers such as dibenzoate esters of various diols such as triethylene glycol and neopentyl glycol improves the crystallinity properties of polyethylene terephthalate.
It is effective for purposes such as improving fluidity and improving the surface gloss of molded products. The method for producing the composition of the present invention is not particularly limited, but preferably aromatic polyester, vinyl copolymer (A), and polyepoxy compound (B) are melted using an extruder. An example is a method of kneading. 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 effects of the present invention will be explained in further detail with reference to Examples below. Examples 1 to 4, Comparative Examples 1 to 3 100 parts by weight of polybutylene terephthalate (PBT) with a relative viscosity of 1.60 was dry blended with vinyl copolymers and polyepoxy compounds in the types and proportions shown in Table 1. The mixture was melt mixed and pelletized using a screw extruder set at 250°C. Next, the obtained pellets were heated to 250°C.
An ASTM bending test piece, a heat distortion temperature measurement test piece, and an Izotz impact test piece (all 1/4 inch wide) were made by molding using a screw-in-line injection molding machine. Table 1 shows the results of measuring the characteristics of these test pieces. In addition, measurements were conducted in the same manner on samples to which no vinyl copolymer and/or polyepoxy compound was added. These results are also shown in Table 1. As is clear from the results in Table 1, even when polybutylene terephthalate is used as the aromatic polyester, the composition of the present invention containing both a vinyl copolymer and a polyvalent epoxy compound does not contain a modifier for both. It is clear that a high heat deformation temperature is maintained by the interaction of the two, and that a synergistic impact resistance improvement effect is produced. Examples 5-6, Comparative Examples 4-5 Vinyl copolymers and polyepoxy compounds of the types and proportions shown in Table 1 were added to 100 parts by weight of polycyclohexane dimethylene terephthalate (PCT) with a relative viscosity of 1.58. dry blend,
Other than setting the melting and forming temperature to 310℃,
Extrusion, molding, and evaluation were performed in the same manner as in Example 1. The obtained results are also shown in Table 1. As is clear from the results in Table 1, even when polycyclohexane dimethylene terephthalate is used as the aromatic polyester, the composition of the present invention containing both a vinyl copolymer and a polyepoxy compound has a high It is clear that it has a heat distortion temperature and impact strength. 【table】

Claims (1)

[Claims] 1 Based on 100 parts by weight of an aromatic polyester selected from polybutylene terephthalate and polycyclohexane dimethylene terephthalate, (A) vinyl consisting of an aromatic vinyl monomer and an α,β-unsaturated cyclic maleimide compound. 5 to 80 weight of system copolymer and (B) polyvalent epoxy compound 0.5
A resin composition containing ~100 parts by weight.