JPS62260856A - Thermoplastic molding resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin compsn. having improved impact resistance, dimensional stability, rigidity and moldability and suitable for use in the production of the outer plates of an automobile, by blending a high-molecular thermoplastic polyester with an arom. polycarbonate, a specified PE and a filler or a reinforcing agent. CONSTITUTION:A resin compsn. contains 35-85wt% high-molecular thermoplastic polyester (A), 5-30wt% arom. polycarbonate (B), 0.1-30wt% linear low-density polyethylene (C) which is a maleic acid-modified ethylene/alpha-olefin copolymer and 5-35wt% filler or reinforcing agent (D). Preferred examples of the component A are poly(ethylene terephthalate), poly(1,4-butylene terephthalate), etc. The component B can be prepd. by using a dihydric phenol and a carbonate precursor. A copolymer having a density of 0.91-0.95, an alpha-olefin content of 15-30wt% and a maleinizing ratio of 0.1-0.3wt% is preferred as the component C.

Description

[Detailed Description of the Invention] ′ (Industrial Application Field) This invention provides improved impact resistance and
This invention relates to a thermoplastic molding composition having dimensional stability, rigidity, and moldability.

(Prior Art) Various attempts have been made to improve the impact resistance of molding resin compositions.

In recent years, with the development of molecular weight control, the use of nucleating agents, and two-step molding methods, poly(ethylene terecrate) has become an important ingredient in injection molding types. Furthermore, poly(1,4-butylene terephthalate) has an extremely high rate of crystallization from the melt, making it very useful as a component in molding compositions.

Furthermore, poly(1,4-butylene terephthalate) injection molded articles exhibit very good dimensional stability even at temperatures close to or significantly above their glass transition temperature.

Also, poly(1,4 butylene terephthalate) is about 30~
Injection molding can be performed at temperatures as low as 60° C. to produce highly crystalline and dimensionally stable molded articles in short cycle times. Great efforts have been made to improve their impact resistance.

For example, Printerman (Brinkmann) et al.
U.S. Pat. No. 3,516,59 discloses that the modifier consists of polyalkyl acrylates, methacrylates and ethacrylates. Nakamura et al. propose polyarylene carbonates and certain polybutadiene graft copolymers in US Pat. No. 3,864,428. Baron et al., in US Pat. No. 4,044,073, discloses aromatic polycarbonates as impact modifiers. Schlichting et al., U.S. Pat.
No. 22,748 discloses that elastomeric graft copolymers having a glass transition IS'lA of -20 DEG C. or less are useful modifiers.

Lane, U.S. Pat. No. 4,034,013 and Farnham et al., U.S. Pat. No. 4,096,202, disclose that useful impact modifiers are multi-stage having a rubbery first stage and a hard final stage. , preferably containing units derived from alkyl acrylates.

For example, in JP-A No. 58-45255, ethylene ethyl acrylate copolymer was added to polybutylene terephthalate in order to improve its impact resistance and ensure a low specific gravity.
The main idea is to add % by weight.

It is also said that adding 1 to 60% by weight of fibers such as glass fiber significantly increases impact resistance, and that pigments, fillers,
It is also stated that flame retardants and stabilizers are added.

However, as described in the examples, these
For example, the notched Izot test at room temperature is 1.2 to 1.
4ft-1b/in (approximately 7.2~8.4kg-cm/
cm), which is too insufficient for use as an automobile exterior panel. In addition, as described in this patent publication, if fibers such as glass fibers are added, 2.11ft-1
Although the surface roughness is improved to 1.2 b/in, the surface roughness is extremely poor and cannot be used as an outer panel of an automobile.

Furthermore, JP-A No. 59-131646 aims to improve compatibility, plate-out property, and mold releasability to improve weld line strength by adding linear low-density polyethylene to thermoplastic polyester. It is.

Furthermore, in the composition described in this patent publication, aromatic polycarbonate is added from 5 to 5 to improve impact resistance.
70 parts by weight, and about 2 to 25 parts by weight of a core-shell type acrylic elastomer, an acrylic copolymer, a vinyl copolymer, etc.

In addition, fillers, reinforcing agents, nucleating agents, fluidity promoters, coloring agents,
It is stated that flame retardants, stabilizers, etc. may be added. It is also stated that glass fiber, mica, etc. are particularly good as reinforcing agents. However, even though linear low-density polyethylene, which is the main component of this composition, is useful for improving weld line strength, as shown in the specific examples, the addition of it significantly deteriorates the impact resistance of the system as a whole. It is something that makes you In addition, it significantly deteriorates physical properties in terms of rigidity, heat resistance, and dimensional stability.

(Problems to be Solved by the Invention) As mentioned above, conventional impact resistance-improving resin compositions have low rigidity because they are not intended for use in automobile exterior panels, such as flexural modulus of 20,000 kg/CIIIz or less. or have poor dimensional stability, for example, a coefficient of linear expansion of 10 x 10-'cm/cm/''C or more,
There was a problem that baking paint could not be applied at the same time as steel.

This invention was made by focusing on such conventional problems, and in order to improve the impact resistance of polyester resin, appropriate amounts of polycarbonate and maleic acid-modified ethylene-α-olefin copolymer were added. The above-mentioned problems were solved by adding an appropriate amount of filler or reinforcing material to improve the bending modulus, improve heat resistance, and reduce the coefficient of linear expansion.

Therefore, this invention consists of the following components: tal high molecular weight thermoplastic polyester resin 35 to 85% by weight (b) aromatic polycarbonate 5 to 30% by weight (C) linear low density polyethylene of maleic acid modified ethylene-α olefin copolymer 0.1-30% by weight 9≦((11) Concerning an improved thermoplastic molding resin composition containing 5-35% by weight of filler or reinforcing material.

The resin composition of the present invention is a thermoplastic composition that can significantly improve impact resistance, rigidity, heat resistance, dimensional stability, and moldability, and can be used in known general molding methods such as injection molding. It is useful in

Polyesters suitable for use as component (a) in the composition include poly(ethylene terephthalate), poly(ethylene terephthalate), poly(1
, 4-butylene terephthalate) and copolyesters. The above copolyesters are preferably those derived from one or more aliphatic and/or aromatic dicarboxylic acids and one or more aliphatic or alicyclic glycols, random copolyesters, and block copolyesters. used. Moreover, the polyester of component (a) may contain a branched component, and the terminal group may be controlled to increase compatibility with other components. Many grades are commercially available as materials that can be used, such as 1401-XO4 manufactured by Toshisha Co., Ltd.

The component (bl) in the composition is blended to improve impact resistance, and various aromatic polycarbonates suitable for use are known and commercially available. For example, U.S. Pat. No. 2,993,835 Specification 4 As seen in 2
It can be produced using a hydric phenol and a carbonate precursor. Moreover, it is also possible to use a copolymer instead of a single polymer of these.

Components in the composition (maleic acid-modified ethylene-alpha olefin copolymer suitable for use as C1) are about 0.
It is preferable to have a density of 91 to 0.95, an α-olefin content of about 15 to 30, and a maleation rate of 0.1 to 0.3% by weight. Maleic acid-modified ethylene-alpha olefin copolymers are also known and are commercially available and readily available.

Fillers or reinforcing materials suitable for use as component (d) in the compositions of the present invention include, but are not limited to, talc, milled glass fiber, flake glass, mica, etc. etc. When these fillers are treated with a silane coupling agent such as aminosilane or a titanium coupling agent, further effects may be obtained. These are used for reinforcement or as a reinforcing material effective for preventing warpage after molding, or as a filler effective for preventing thermal expansion at high temperatures (up to 100° C.). The composition may also contain stabilizers such as hindered phenolic antioxidants and phosphites, flow improvers, flame retardants, and nucleating agents.

The composition and proportions of the components of the composition of the present invention vary depending on the required physical properties specific to that part, even in the case of an automobile exterior panel. However, even in various combinations, the component (alO
35 to 85% by weight of high molecular weight thermoplastic polyester, 5 to 30% by weight of aromatic polycarbonate as component (b), 0.1 to 30% by weight of linear low density polyethylene as component (C),
When the filler or reinforcing material of component (d) is present in a proportion of 5 to 35% by weight, a material satisfying the required physical properties that can be specifically applied to automobile outer panels is obtained.

If the amount of component (a) added is less than 35x4, the moldability will be poor (
On the other hand, if it exceeds 85% by weight, no improvement in impact properties can be expected. If the amount of component (BL added) is less than 5%, the effect of improving impact properties will not be obtained, and as the amount added increases, impact properties will improve, but if it exceeds 30%, fluidity will deteriorate and moldability will deteriorate. Next, the amount of component (C) added is 0.
．． If it is less than 1% by weight, it is too small to obtain the effect of adding it, and by increasing the amount of addition to 0.1% by weight or more, the impact properties will improve, but if it exceeds 30% by weight, the heat resistance will deteriorate and the steel At the same time, baking paint cannot be applied. In addition, (if the amount of the dl component added is less than 5% by weight, the effect of adding it will not be obtained; on the other hand, if the amount added is more than 5% by weight, the rigidity will improve, but if it exceeds 35% by weight, the elongation will decrease. , the impact properties deteriorate.

The composition of this invention can be manufactured by conventional methods. For example, one method is to simultaneously charge a thermoplastic polyester, an aromatic polycarbonate, a maleic acid-modified ethylene-α-olefin copolymer, and a filler or reinforcing material into a single screw extruder to produce moldable pellets. As a result, the highly compatible thermoplastic polyester and aromatic polycarbonate are uniformly kneaded, and the maleic ethylene-α-olefin copolymer and filler or reinforcing agent are uniformly dispersed in the matrix. .

Alternatively, the components (bl~(di) and other optionally added ingredients can be mixed with the thermoplastic polyester resin in powdered or granular form and shaped directly, e.g. by injection molding techniques. .

(Example) This invention will be explained by the following examples and comparative examples.

On the other hand, example 1.　Flies examples 1 to 4 Made of polybutylene terephthalate.

1401-XO4 (trade name), aromatic polycarbonate manufactured by Mitsubishi Gas Chemical OS, 52000 trade name, ethylene-α olefin copolymer manufactured by Mitsui Petrochemical Industries 0
1, Tafmer P (PO680) (trade name), or a maleated ethylene-α-olefin copolymer manufactured by Mitsui Petrochemical Industries Ltd., Tafmer MA8510 (trade name), and as a filler talc (manufactured by Asada Seifun Co., Ltd., 13R). ),
Polyester elastomer (manufactured by DuPont, Hytrel 4056. FJ product name), ethylene propylene (E
P) Rubber (JSR, EPOI), ethylene-propylene-diene terpolymer (manufactured by Sumitomo Chemical Industries, Ltd., Nisprene 808. trade name) in the proportions shown in Table 1, with an antioxidant stabilizer added, The mixture was put into a single screw extruder, kneaded and extruded at 240°C, and granulated.

Each of the obtained pellets was molded into a test piece molded product at 260'C using an injection molding machine, and various tests were conducted.

Table 2 shows the physical property test results.

(Effects of the Invention) As explained above, the thermoplastic molding resin composition of the present invention includes (al high molecular weight thermoplastic polyester, (
By containing specific amounts of bl aromatic polycarbonate, (C) maleic acid-modified ethylene-α-olefin copolymer, and (d) filler or reinforcing material, physical properties such as impact resistance are significantly improved as a molding resin composition. It was done.

Claims (1)

[Claims] 1. (a) 35-85% by weight of high molecular weight thermoplastic polyester, (b) 5-30% by weight of aromatic polycarbonate, (c) Linear maleic acid-modified ethylene-α-olefin copolymer An improved thermoplastic molding resin composition comprising 0.1 to 30% by weight of low density polyethylene and (d) 5 to 35% by weight of a filler or reinforcing material.