JPS61264045A - Thermoplastic resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thermoplastic resin composition that has excellent moldability and excellent mechanical and thermal properties.

[Conventional technology]

Saturated polyester resin generally has a variety of excellent properties, including mechanical and electrical properties, but has problems such as poor dimensional stability, impact resistance, and heat resistance, making it difficult to use as a molding material. is restricted.

On the other hand, polycarbonate resins have excellent heat resistance, impact resistance, and dimensional stability, but have disadvantages such as poor flowability, problems in molding process, and poor chemical resistance.

As a method to improve the drawbacks of saturated polyester resins and polycarbonate resins, for example, a method is proposed in which a polyester resin and a polycarbonate resin are uniformly mixed in a molten state to improve the processability and physical properties of both resins. 14035, JP-A-48-54160, JP-A-49-107354, etc.
In the composition thus obtained, the mutual dispersibility of the two mixed components is poor, and the appearance of the molded product is poor or the molded product is likely to be uneven. In addition, it has the disadvantage that it has insufficient physical impact resistance and cannot be used in fields where impact strength is required.

As a method of improving the impact resistance of such a composition, for example, a method of mixing three components of a polycarbonate resin, a polyester resin, and a butadiene-based graft copolymer (Japanese Patent Application Laid-open No. 49-41442), or a method of mixing a polycarbonate resin, a polyester resin, and A method of mixing three components of acrylate rubber (Japanese Unexamined Patent Publication No. 129246/1983) has been proposed.

However, the former butadiene-based polymer is susceptible to oxidative deterioration due to unsaturated bonds in the polymer due to light and heat, for example when producing polymers or resin compositions or when molded products are used at high temperatures for long periods of time. It has five drawbacks: it deteriorates due to heat, and when used outdoors for a long time, it also deteriorates due to light, reduces impact strength, and has poor weather resistance.

In addition, although the latter method of mixing acrylate rubber has some effect of improving impact resistance at room temperature, it is still insufficient, and furthermore, impact resistance in low temperature atmosphere is low. Application to applications requiring higher impact resistance is limited.

[Problems to be solved by the invention] In view of the above-mentioned current situation, it is desirable to have a well-balanced material that has excellent moldability and impact resistance, especially impact resistance in a low-temperature atmosphere, and excellent thermal properties and chemical resistance. As a result of intensive studies, with the aim of providing a resin composition with excellent characteristics,
The inventors have discovered that a resin composition that meets the above objectives can be obtained by blending a specific amount of a specific resin, and have thus arrived at the present invention.

[Means for solving problems]

The thermoplastic resin composition of the present invention contains 5 to 95% by weight of a saturated polyester resin (A) and 5 to 95% by weight of a polycarbonate resin (B).
~95% by weight, acrylate rubber-containing polymer (C) 1
~40% by weight and 1~20% by weight of ethylene-alkyl acrylate copolymer (D).

The saturated polyester resins used in the present invention are comprised of polyethylene terephthalate, polytetramethylene terephthalate and mixtures thereof. These are synthesized by known methods, for example, from dimethyl terephthalate and ethylene glycol or 1,4-butanediol, but if necessary, diols such as 1,3-propanediol and dicarboxylic acids such as isophthalic acid may be added during synthesis. A small amount of copolymerized polymer may also be used.

The intrinsic viscosity [η] of these polymers is in the range of 0.4 to 1.5 as measured at 25° C. in a mixed solvent of equal amounts of tetrachloroethane/phenol.

Polycarbonate resin (as Bl, polycarbonate based on aromatic bishydroxy compounds, preferably bis=(4-hydroxyphenyl)-propane-2,
It is a polycarbonate composed of two units (bisphenol A).

An acrylate rubber-containing polymer (C1 is a polymer containing 20% by weight or more of an acrylate rubber component (at), and in the presence of this rubber component (at), one or more vinyl compounds (BL) It is produced by polymerizing a mixture.

The acrylate rubber component (&) mentioned herein includes alkyl acrylates and/or alkyl methacrylates in which the alkyl group has 2 to 1 carbon atoms, such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, n-octyl methacrylate, etc. 70% by weight or more of these (meth)acrylate monomers and other vinyl monomers copolymerizable with them, such as methyl methacrylate, styrene, acrylonitrile, vinyl acetate, etc. % by weight or less.

Up to 5% by weight of crosslinking agents based on such rubbery polymers, such as evadivinylbenzene, ethylene dimethacrylate, triallyl cyanurate, triallyl isocyanurate,
Polyfunctional monomers such as 1,3-butylene dimethacrylate can be used.

In addition, an acrylate rubber component (a vinyl compound (BL) is a monomer selected from aromatic vinyl compounds such as styrene and α-methylstyrene, and alkyl methacrylates such as methyl methacrylate and ethyl methacrylate). One or more of these monomers, or a mixture of one or more of these monomers with other vinyl monomers, such as vinyl cyanide monomers such as acrylonitrile and methacrylate, and vinyl esters such as vinyl acetate and vinyl propionate. Polymerization can be produced by bulk polymerization, suspension polymerization, or emulsion polymerization.Generally, emulsion polymerization≧tip ±□□□ copolymers contain ethylene and an alkyl group having 2 carbon atoms. ~8 alkyl acrylates, such as ethyl acrylate, propyl acrylate,
It is a copolymer with a monomer selected from phthyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, etc., and is a component that improves the impact resistance of the composition in a low-temperature atmosphere.

The thermoplastic resin composition of the present invention can be produced by any method of mixing solid substances, such as a method using a Banbury mixer 1 heated roll or an extruder.

As for the compounding method, the saturated polyester resin (
The simplest method is to simultaneously mix Al, polycarbonate resin (Bl, acrylate rubber-containing polymer (C1), and ethylene-alkyl acrylate copolymer (Dl) and granulate it with an extruder, but there are particular restrictions on the blending method. It's not something you do.

The blending ratio of each component is as follows: 5-95% by weight of the component (Al), 5-95% by weight of the component (Bl), 1-40% by weight of the component (C1, preferably 1.5-30% by weight), and the component (Dl). 1 to 20% by weight, preferably 1 to 10% by weight.In the composition of the present invention, if the amount of the component is less than 5% by weight, the resulting composition may have insufficient solvent resistance. On the other hand, if the amount exceeds 95% by weight, the dimensional stability, heat distortion temperature, impact strength, etc. of the composition will be insufficient.In addition, in the composition of the present invention, if the amount of component (B) exceeds 5% by weight If the amount is less than 95% by weight, the resulting composition will have poor dimensional stability (and the heat distortion temperature will not improve, and if it exceeds 95% by weight, the moldability will be insufficient.Furthermore, in the composition of the present invention, the component ( C
If 1 is less than 1% by weight, the impact strength of the resulting composition will not be improved, and if it exceeds 40% by weight, the heat distortion temperature of the composition will be significantly lowered. In the composition, if the amount of the component (Dl) is less than 1% by weight, the impact strength of the resulting composition, especially in a low temperature atmosphere, will not be improved, and if it exceeds 20% by weight, Extrusion workability is poor, and the heat distortion temperature of the resulting composition is significantly lowered.

In the composition of the present invention, stabilizers such as phenol-based and phosphite-based stabilizers, mold release agents such as ethylene bisstearamide, rice fatty acid ester, and wax,
Ultraviolet absorbers, fillers, modifiers, dyes and pigments, flame retardants, etc. can be added.

〔Example〕

Hereinafter, the present invention will be described in more detail in Examples.

Note that "parts" and "%" in the examples are all based on weight. In addition, each physical property test method was measured by the method shown below.

(1) Impact resistance: ASTM D-25
6-56 (21 heat deformation m coal...ASTM D-648
264 psl Examples 1 to 9, Comparative Examples 1 to 5 Production of acrylate rubber-containing polymer (c) 180 parts of ion-exchanged water purged with nitrogen was placed in a reaction vessel, and boric acid O,
45 parts, anhydrous sodium carbonate 0.045 parts, potassium oleate 2.0 parts, persulfuric acid power! Dissolve 70.15 parts, 70
'C n-butyl acrylate 49.75
1.3-butylene dimethacrylate and 0.25 parts of 1.3-butylene dimethacrylate were added dropwise over a period of 3 hours, followed by further polymerization for 1 hour. Thereafter, a mixture of 49 parts of n-butyl acrylate and 1 part of allyl methacrylate was added dropwise to this reaction mixture over 2 hours while maintaining the temperature at 70°C, and polymerization was further carried out for 1 hour to obtain an acrylate rubber component (at). Ta.

Next, 100 parts of the above acrylate rubber component (as polymer solid content), 100 parts of ion-exchanged water, 0.2 part of sodium formaldehyde sulfoxylate), and 0.5 part of potassium oleate were added and kept at 70°C. A mixture of 30 parts of methyl methacrylate, 10 parts of styrene, and 0.15 parts of t-butyl hydroperoxide was added dropwise over 90 minutes, followed by further polymerization for 1 hour. Next, a mixture of 20 parts of methyl methacrylate and 0.07 parts of t-butyl hydroperoxide was added dropwise over 1 hour to advance polymerization, and after completion of the addition, polymerization was continued for another 1 hour.

After the reaction was completed, the latex was poured into an aqueous sulfuric acid solution and coagulated by acid precipitation, followed by filtration, washing with hot water, dehydration, and drying to obtain an acrylate rubber-containing polymer (C1).

Production of resin composition The above polymer (C1 and polytetramethylene terephthalate (in a mixed solvent of equal amounts of phenol/tetrachloroethane, 2
The intrinsic viscosity [η] measured at 5°C is 1.15), the polycarbonate resin and the ethylene-alkyl acrylate copolymer were premixed in the proportions shown in Table 1 in a V-type blender, and then in a 25φ extruder. Cylinder temperature 250
Melt mixed and pelletized at ~280°C.

Next, test pieces for evaluation were prepared from the pellets using a 36φ, 5 oz injection molding machine under conditions of a cylinder temperature of 270°C and a mold temperature of 80°C.

Table 1 shows the results of the evaluation.

The results in Table 1 show that the resin composition of the present invention has excellent heat resistance and impact resistance.

Examples 10-12, Comparative Examples 6 to 8 The polycarbonate resin used in Examples 1 to 5, acrylate rubber-containing polymer (C1, ethylene-alkyl acrylate copolymer and polyethylene terephthalate (phenol/tetrachlor) as the saturated polyester resin) The intrinsic viscosity measured at 25°C in a mixed solvent of equal amounts of ethane is [η] = 0.72) was premixed in a V-type blender at the ratio shown in Table 2, and then the mixture was premixed in a V-type blender using a 25φ extruder. A pellet was produced by melt-mixing at a temperature of 250 to 280°C.

Next, the obtained pellets were molded using a 36φ, 5oz injection molding machine with a cylinder temperature of 280°C and a mold temperature of 80°C.
A test piece for evaluation was prepared under the conditions of ℃, and the impact strength was measured. The results are shown in Table 2.

〔Effect of the invention〕

The composition of the present invention having the above-mentioned structure maintains good chemical resistance, has excellent thermal properties and impact resistance, especially impact resistance in a low-temperature atmosphere, and has excellent thermal stability during molding. Because of its excellent properties, there is little deterioration in the resulting molded products, making it extremely useful for applications in fields where impact resistance is required, such as automobile parts.

Claims (1)

[Claims] Saturated polyester resin (A) 5-95% by weight, polycarbonate resin (B) 5-95% by weight, acrylate rubber-containing polymer (C) 1-40% by weight, and ethylene-
A thermoplastic resin composition comprising 1 to 20% by weight of an alkyl acrylate copolymer (D).