JPS5966448A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:A composition that is composed of a polycarbonate resin, a polyester resin and a specific modified alpha-olefin polymer, thus showing improved impact strength as well as high moldability, chemical resistance and weather resistance. CONSTITUTION:100pts.wt. of a composition consisting of (A) 97-30pts.wt. of a polycarbonate resin and (B) 3-70pts.wt. of a polyester resin are combined with (C) 1-20, preferably 3-18pts.wt. of a modified alpha-olefin polymer made by grafting 0.01-5, preferably 0.05-4wt% of vinyl compounds bearing polar groups onto an alpha-olefin polymer. Suitable component C contains an ethylene-alpha-olefin copolymer from 99.5-30mol% of ethylene and 0.5-70mol% of an alpha-olefin as well as a vinyl compound of an unsaturated dicarboxylic acid or its derivative or anhydride such as maleic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin composition comprising a polycarbonate resin, a polyester resin, and a specific modified α-olefin polymer. More specifically, the present invention relates to a thermoplastic resin composition that is excellent in moldability, chemical resistance, and can provide molded articles with improved Izod impact strength.

Although polycarbonate has excellent mechanical properties, thermal properties, and electrical properties, it has poor chemical resistance and moldability. Furthermore, polyester is almost insoluble in solvents, has high water resistance, heat resistance, and oxidation resistance, and is used in large quantities as films and fibers. However, when polyester is injection molded, although it has good chemical resistance, it has insufficient impact resistance, thermal deformation humidity, and dimensional stability, and is therefore impractical.

Therefore, methods have been proposed that maintain the advantages of polycarbonate and polyester while simultaneously compensating for their disadvantages.

For example, Japanese Patent Publication No. 36-14035 discloses a composition of polycarbonate and polyester. However, when polycarbonate and polyester are blended,
Although the chemical resistance and moldability, which are disadvantages of polycarbonate, are improved, the high impact resistance of polycarbonate is significantly impaired.

Regarding blends of 1 polycarbonate, polyester and polyolefin, Japanese Patent Publication No. 39-2043
It is proposed in No. 4. According to this method, deterioration in impact resistance can be prevented to some extent, but it is still not sufficient. That is, even if a homopolymer of α-olefin such as polyethylene, polypropylene, polybutene, or polystyrene is added to a mixture of polycarbonate and polyester, the decrease in impact resistance can be improved to some extent, but the impact resistance is dependent on the thickness. . In addition, phase separation is likely to occur, and moldability is not sufficient.

That is, a molded article obtained from a composition formed by blending a polyolefin such as polyethylene or polypropylene with a mixture of polycarbonate and polyester has a thickness of 6 to 6.
When the thickness is about 7 mm, the effect of improving impact resistance by adding polyolefin is recognized. However, the thickness is 1-3m
The impact resistance of commonly used molded products of about 100 m is hardly improved. In addition, phase separation of the molded product was observed,
In particular, the phase separation at the gate of the molded product is severe and the skin is likely to peel off.

Furthermore, in JP-A No. 51-39749, an ethylene-vinyl acetate copolymer is blended into a mixture of polycarbonate and polyester to improve the impact resistance even when the thickness of the molded product is thin. It is disclosed that there is no separation and finishing processing of the gate part becomes easy. However, the improvement effect of ethylene vinyl acetate copolymer cannot be said to be sufficient.

On the other hand, JP-A-49-44442 discloses a composition obtained by graft copolymerizing a vinyl monomer such as a methacrylic acid ester, an aromatic monovinyl compound, or a vinyl cyanide compound to a composition of an aromatic polyester and an aromatic polycarbonate. It has been disclosed that impact properties can be improved by blending a butadiene-based polymer. However, even if a butadiene-based graft copolymer obtained by graft copolymerizing these vinyl compounds is blended, the effect of improving impact resistance is not sufficient, and furthermore, the weather resistance is poor due to the unsaturated bonds in the polybutadiene.

The present invention maintains excellent moldability, dimensional stability, chemical resistance, and weather resistance of the composition by blending a specific modified α-olefin polymer into the composition of polycarbonate resin and polyester resin. At the same time, the present invention provides a composition with improved impact resistance, no phase separation, and improved moldability.

The gist of the present invention is that polycarbonate resin (A) 97-
About 0.01 to about 5% by weight of a vinyl compound having a polar group is grafted onto an α-olefin polymer to 100 parts by weight of a composition consisting of 30 parts by weight and 3 to 70 parts by weight of polyester resin (B). Polymerized modified α-olefin polymer (
It relates to a thermoplastic resin composition characterized in that c) consists of 1 to 20 parts by weight.

Polycarbonates used in the invention include, for example, evabis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(
Bis(hydroxyaryl)alkanes and bis(hydroxyaryl)ethers represented by 3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(6,5-dichloro-4-hydroxyphenyl)propane, etc. , bis(hydroxyaryl) sulfoxide, bis(
Examples include polymers obtained by reacting one or more dihydroxy compounds such as hydroxyaryl sulfone with carbonate precursors such as phosgene and diphenyl carbonate by a known method; for example, the intrinsic viscosity is that of methylene chloride. Approximately 0.2 to 1.0 measured at 20"C
Some resins can be used.

The polyester used in the present invention is a polymer or copolymer obtained by condensation reaction of an aromatic dicarboxylic acid or its ester-forming derivative and a diol or its ester-forming derivative as main raw materials. More specific examples include molding resins such as polyethylene terephthalate, polyethylene isophthalate, polytrimethylene terephthalate, and polytetramethylene terephthalate. The molecular weight of these polyesters is not particularly limited, but when O-chlorophenol is used as a solvent, 2
Examples include those having an intrinsic viscosity of about 0.2 to 2.0 when measured at 5°C. These polyesters may be copolymerized polyesters obtained by copolymerizing other dicarboxylic acids and/or diols.

The modified α-olefin polymer used in the present invention is α
- Obtained by graft polymerizing a vinyl compound having a polar group onto an olefin polymer. α-O L, Fin'1%
Polymer L Ha, ethylene, propylene, 1-butene, 1
- Homopolymers of α-olefins such as pentene, 1-hexene, 1-heptene, 6-methyl-1-butene, 4-methyl-1-pentene, 1-octene, 1-decene, and two or more α-olefins There are copolymers consisting of polyethylene, polypropylene, ethylene propylene copolymer, ethylene-1-butene copolymer, propylene-1-butene copolymer, ethylene-4-methyl-1-bentene copolymer, and polypropylene. Examples include -1-butene, poly-4-methyl-1-pentene, and 4-methyl-1-pentene-1-decene copolymer. Among these, a copolymer of ethylene and an α-olefin having 3 to 6 carbon atoms is preferably used. Among them, ethylene is about 99.8 to about 65 mol%, especially about 99.5 to about 60 mol%, and α-olefin is about 0.2 to about 65 mol%, especially about 0.5 to about 70 mol%. Ethylene-α-olefin copolymers are preferred. The crystallinity is about 80 to about θ%, especially about 60 to about 5%, and the melt flow rate (AS
TM 123857T (190° C.) in the range of about 0.05 to about 50, particularly about 0.1 to about 20, are suitable as raw materials.

Vinyl compounds with polar groups include unsaturated carboxylic acids and their derivatives, such as acid halides, amides, imides, anhydrides, esters, etc. Specifically, acrylic acid, methacrylic acid, maleic acid, and tetrahydrophthalic acid. , itaconic acid, citraconic acid, nadic acid (endocys-bicyclo(2,2,1)hept-5-ene-2+3-dicarboxylic acid), acryloyl chloride, methacryloyl chloride, maleyl chloride, maleyl bromide, acrylamide, acrylmethylamide 1 Methacrylamide, methacrylmethylamide, maleimide, maleic anhydride, nadic anhydride, citraconic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, monomethyl maleate, dimethyl maleate, glycidyl acrylate, glycidyl methacrylate, etc. be done.

Among these vinyl compounds, unsaturated dicarboxylic acids such as maleic acid, nadic acid, phthalic acid, itaconic acid, and citraconic acid, and derivatives thereof, particularly anhydrides, are preferred.

In order to graft-polymerize a vinyl compound onto an α-olefin polymer, various conventionally known methods can be employed. For example, there is a method in which an α-olefin polymer is melted or dissolved in a solvent, and a vinyl compound is added to perform graft polymerization. During graft polymerization, other vinyl monomers, such as styrene, etc. may also be present. In particular, a modified α-olefin polymer obtained by efficiently performing graft polymerization using a radical generator,
There is little thermal decomposition of the α-olefin polymer, and even if the blending ratio in the composition of the present invention is small, it is well dispersed, and impact resistance and moldability are improved.

Radical generators include organic peroxides, organic bersesters such as benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, diter
Examples include t-butylperoxide, tert-butylberacetate, tert-butylberbenzoate, and other azo compounds such as azobisisobutyronitrile and dimethylazoisobutyrate.

In graft polymerization, the α-olefin polymer used,
Depending on the type of vinyl compound or radical generator,
The reaction temperature and reaction time can be changed as appropriate.

The modified α-olefin polymer used in the present invention has a vinyl compound grafting ratio of about 0.01 to about 5% by weight,
Particularly preferably, the content should be adjusted within the range of about 0.05 to about 4% by weight, and if necessary, the modified α-olefin polymer and the unmodified α-olefin polymer may be mixed to form this polymer. It can also be adjusted within a range.

When the grafting ratio of the vinyl compound is less than about 0.01% by weight, the compatibility with the matrix polymers of polycarbonate and polyester is poor, and the phase separation at the gate of the molded article is severe and the skin is likely to peel off. Furthermore, the impact strength is reduced.

If the amount exceeds about 5% by weight, crosslinking is likely to occur if the graft polymer is an ethylene polymer, and if the graft polymer is a propylene polymer, the effect of improving impact strength will be reduced due to side reactions of decomposition.

In addition, the modified α-olefin polymer used in the present invention has crystallinity and melt flow rate values of the raw material α-
The value is almost the same as that of olefin polymers. Among them,
The modified ethylene-α-olefin copolymer desirably has a crystallinity of about 80 to about 0, particularly about 60 to about 5.
7TC190℃) is about 0.05 to about 50, especially about 0
．． A range of 1 to about 20 is desirable.

Polycarbonate resin, polyester resin and modified α
- Conventionally known methods are employed to mix the olefin polymers to form a composition. For example, there is a method of melting and mixing using an axle or multi-screw extractor, or a double screw mixer, and the temperature is about 230 to about 330"c1, preferably about 250 to about 300°C.
at a temperature of about Q, 5 to about 50 minutes, particularly preferably about 1
It is desirable to mix the lines for about 10 minutes.

The compositions of the present invention contain a polycarbonate resin of about 97 to about 6
Modified α-olefin yarn The polymer contains about 1 to about 20 parts by weight, especially about 5 to about 20 parts by weight.
The composition is formulated in a proportion of about 18 parts by weight.

If the compositions of the polycarbonate resin and polyester resin are within the above range, the composition will have the characteristics of both. If the blending ratio of the modified α-olefin polymer is less than 1 part by weight, the effect of improving moldability and impact resistance will be insufficient, and if it exceeds 20 parts by weight, rigidity and heat resistance will decrease.

The composition of the present invention can be molded by various conventionally known methods. For example, it is molded into films, sheets, bottles, housings, and other various shapes by methods such as injection molding, extrusion molding, compression molding, and foam molding.

Furthermore, the composition of the present invention may contain conventionally known additives within a range that does not impair the purpose of the present invention. for example,
Fibrous reinforcing agents such as glass fiber, carbon fiber, and metal fiber, fillers such as silica, alumina, silica alumina, clay, glass beads, carbon black, and titania, aromatic
Flame retardants such as halides, stabilizers such as phosphite esters and phosphate esters, other lubricants, ultraviolet absorbers, colorants, etc. are blended as necessary.

The composition of the present invention has improved impact resistance without impairing the excellent characteristics of polycarbonate resins and polyester resins, has low thickness dependence of impact resistance, has no phase separation, has moldability, Due to its improved weather resistance, it can be used in a wide range of applications, including precision machinery, transportation machinery, the electrical sector, and automobiles.

Examples are shown below.

Example 1 Polyethylene (PE) (MFR 190°C, 13g/1
[]mi, n, crystallinity 65 crystallinity 65 type 11100 water maleic acid graft modified ethylene polymer [MFRl
90"C%"5g710m1n% crystallinity 62%], polycarbonate resin (Yodai Kasei, Panrai L-1250) and polyester resin (Kanebo,
EFo-6) was mixed in the ratio shown in Table 1 using pre-goo to prepare a tri-blend product. This tri-blend composition was supplied to a L/D 28, 25 mmφ extruder (full light type screw) at 270°C, and
The mixture was kneaded and granulated by passing the mixture through the tube once.

Next, use a Toshiba l5-50 injection molding machine under the following conditions (cylinder temperature 290℃, injection pressure 1000!7/
A physical property test piece was prepared at an injection time of 10 seconds and a mold temperature of 80''C, and its physical properties were evaluated using the following method.

Izot impact strength (rz): Measured according to ASTM D-256 using a notched test piece with a thickness of t/s.

Bending rigidity, bending strength; using a 1/8" thick test piece,
Flexural modulus FM (kg/
2), the bending yield strength FS (kg/(7)2) was measured. In addition, the bending yield strength F S (k
g/cyn2) was measured in the same manner.

Heat distortion temperature (HDT): Measured under 18-6 kq/2 load conditions using a 1/4" thick test piece according to ASTM D-648.

Moldability; ASTM D-121 Layer peeling; The condition of layer peeling at the gate portion of the injection molded test piece was visually determined.

The results are shown in Table 1.

Example 2.3, Comparative Example 6 Ethylene-propylene copolymer (EPR) (ethylene content 80 mol%, MFR (190°C) (co=44 g/
10 minutes, crystallinity 5%] Modified ethylene/propylene cofi polymer (MFr ((+9 (1°C) 0-38
g/I Qmj-n, crystallinity 4%] was carried out in the same manner as in Example 1.

Example 4 Ethylene, butene copolymer (EBR) (ethylene content 85 mol%, +xFR (190″C) 4-D g/
10m in.

[Crystallinity 17%] 100 parts by weight of maleic anhydride was added to 100 parts by weight.
6 parts by weight graft copolymerized modified ethylene, butene copolymer (MFR (190°C) 1-65g/10m1
Example 1 was carried out in the same manner as in Example 1, except that the crystallinity was 15%].

Example 5 Nadic anhydride grafted modified ethylene polymer (Nadic anhydride content 0-2g/10ogpE.

MFR (190°C) 2.0 g/10mln, the base ethylene polymer (P'E) is the same as Example 1)
The same procedure as in Example 1 was carried out except that .

Comparative Example 5 Maleic anhydride graft modified ethylene polymer (maleic anhydride content 5.8 g/100 g-pE.

The same procedure as in Example 1 was conducted except that MFR (190'C) was 0.01 g/10 min, crystallinity was 61%, and the base ethylene polymer (PE) was the same as in Example 1.

Comparative Example 6 Ethylene polymer (MFR (190”C) 13g/10m
1. n.

〇 Using crystallinity of 65%] Comparative example 7

Claims (2)

[Claims] (1) For 100 parts by weight of a composition consisting of 97 to 30 parts by weight of polycarbonate resin (A) and 3 to 70 parts by weight of polyester resin (B), 0 parts of a vinyl compound having a polar group in the α-olefin polymer was added. .01 to 5% by weight of graft-polymerized modified α-olefin polymer (0) is 1 to 2
A thermoplastic resin composition comprising 0 parts by weight. (2) The composition according to claim (1), wherein the vinyl compound having a polar group is a compound selected from unsaturated carboxylic acids and derivatives thereof.