JP2893185B2 - Polycarbonate / polyester resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a resin composition containing an aromatic polycarbonate and an aromatic polyester, and more particularly to the resin composition characterized in that a molded article has no pearl luster. .

[Conventional technology]

In order to improve the impact resistance of a resin composition comprising an aromatic polycarbonate and an aromatic polyester, selected from ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, polyester elastomer and ethylene-ethyl acrylate copolymer It has been known to incorporate a thermoplastic soft resin or a butadiene-based graft copolymer (Japanese Patent Publication Nos. 58-13588 and 55-9435). However, although the impact resistance is improved by the technique, pearl luster appears on the surface of the molded article, which is not preferable for many molded article applications. This pearl luster is conspicuous when the molded article is colored, especially when it is black, and has the appearance of an oil film on water.

[Problems to be solved by the invention]

An object of the present invention is to improve impact resistance without causing the problem of pearl luster of a molded article as described above.

[Means for solving the problem]

The present invention provides, in a resin composition containing an aromatic polycarbonate and an aromatic polyester, 0.5 to 15 parts by weight based on a total of 100 parts by weight of 30 to 80 parts by weight of the aromatic polycarbonate and 70 to 20 parts by weight of the aromatic polyester. A resin composition containing a copolymer mainly composed of an α-olefin and a glycidyl ester of an α, β-unsaturated acid (however, this composition comprises a butadiene-based copolymer and a methacrylic acid ester, an aromatic monovinyl compound and A butadiene-based graft copolymer obtained by graft-copolymerizing one or more vinyl monomers selected from the group consisting of vinyl cyanide compounds,
Ethylene and an α-olefin, an ethylene-based copolymer mainly containing an ethylenically unsaturated monomer or a diene monomer,
And a case where a copolymer of ethylene and an unsaturated carboxylic acid ester is contained).

In the copolymer mainly comprising an α-olefin and a glycidyl ester of an α, β-unsaturated acid used in the present invention, examples of the α-olefin include ethylene,
Propylene, butene-1, isobutylene, pentene
1, hexene-1, heptene-1, octene-1, dodecene-1, 4-methylpentene-1 and the like.
Of these, particularly preferred are ethylene and propylene. Glycidyl esters of α, β-unsaturated acids typically include glycidyl methacrylate and glycidyl acrylate. In addition, other vinyl compounds may contain a relatively small amount as a comonomer,
For example, styrene, vinyl acetate, methyl methacrylate, methyl acrylate, ethyl acrylate, vinyl chloride, α-methylstyrene, divinylbenzene, acrylic acid, tetrafluoroethylene, difluoroethylene,
Examples include vinylidene chloride, acrylonitrile, and acrylamide. The copolymer may be any of a random copolymer, a block copolymer, and a graft copolymer.

The copolymer is mixed in a proportion of 0.5 to 15 parts by weight, preferably 1 to 15 parts by weight, based on 100 parts by weight of the total of the aromatic polycarbonate and the aromatic polyester. If the amount is less than this, the improvement of the impact resistance is insufficient, while if it is more than this, the heat resistance and the mechanical strength decrease.

The aromatic polycarbonates used in the present invention are known per se and can be made by reacting a dihydric phenol with a carbonate precursor such as phosgene, haloformate, or a carbonate ester. Generally, this aromatic polycarbonate has a repeating unit of the following structural formula.

In the formula, A is a divalent aromatic residue of a dihydric phenol used in the above-mentioned polymer formation reaction. The aromatic polycarbonate used in the present invention has an intrinsic viscosity (in methylene chloride
It is preferably about 0.30 to 1.00 (measured at 25 ° C, unit dl / g). The dihydric phenol used to form such an aromatic polycarbonate is a mononuclear or polynuclear aromatic compound in which two hydroxyl groups are each bonded to a carbon atom of an aromatic nucleus as a functional group. Generally, bisphenol A
And aromatic polycarbonates derived from phosgene. A more detailed description of aromatic polycarbonates can be found in, for example, JP-A-63-215763.

The aromatic polyester used in the present invention itself is also known, and a polymer or copolymer obtained by a condensation reaction containing an aromatic dicarboxy acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof as main components. It is. As the aromatic dicarboxylic acid component, for example, terephthalic acid, dicarboxylic acid having a benzene nucleus such as isophthalic acid, naphthalene-1,5-dicarboxylic acid, dicarboxylic acid having a naphthalene nucleus such as naphthalene-2,7-dicarboxylic acid or the like Ester-forming derivatives and the like. In addition, a small amount of a dicarboxylic acid other than the aromatic dicarboxylic acid, for example, adipic acid, sebacic acid or an ester-forming derivative thereof may be used. As the diol component, glycols represented by the formula HO (CH ₂ ) _n OH (n is an integer of 2 to 10), for example, ethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, cyclohexanediol, neopentyl glycol, cyclohexanedimethanol , And 1,4
And diols having an aromatic ring such as bisoxyethoxybenzene and bisphenol A, and ester-forming derivatives thereof. Preferred aromatic polyesters are poly (1,4-butylene) terephthalate, polyethylene terephthalate, 1,4-cyclohexylene dimethylene terephthalate / isophthalate copolymer, especially poly (1,4-butylene) terephthalate. Its molecular weight is preferably that of phenol and tetrachloroethane.
Those having an intrinsic viscosity of 0.50 or more, particularly preferably 0.55 or more, measured at 30 ° C. using a 1: 1 weight ratio mixture as a solvent are used.

30 aromatic polycarbonates and aromatic polyesters
It is used in a weight ratio of 8080 to 70-20, preferably 40-70 to 60-30.

The resin composition of the present invention may contain, in addition to the above components, any conventional additives such as pigments, dyes, reinforcing agents, fillers, heat-resistant agents,
An antioxidant, a weathering agent, a lubricant, a release agent, a crystal nucleating agent, a plasticizer, a flame retardant, a fluidity improver, an antistatic agent and the like can be included.

The resin composition of the present invention can be obtained by mixing the above components in any order, and generally a melt mixing method is desirable. There is no particular limitation on the temperature and time required for melt mixing, and they can be appropriately determined depending on the composition of the material. Examples of the mixing device include an extruder, a Banbury mixer, a roller, a kneader, and the like.

The resin composition of the present invention is particularly suitable for molding by injection molding and extrusion molding, and the present invention also includes such molded articles.

It is noted here that it is known to incorporate copolymers of α-olefins and certain glycidyl esters of α, β-unsaturated acids into polycarbonate or polyester. JP-A-57-125253 discloses a polycarbonate having improved impact characteristics by mixing a polycarbonate with a copolymer of an α-olefin and glycidyl (meth) acrylate. JP-B-58-47419 discloses that impact characteristics are improved by mixing a copolymer of an α-olefin and glycidyl methacrylate into an aromatic saturated polyester. JP-A-55-137155 discloses a composition comprising a polyalkylene terephthalate and a fibrous or granular reinforcing agent mixed with a glycidyl ester of an α-olefin and an α, β-unsaturated acid to increase the surface gloss. And improving impact resistance and rigidity.

The above-mentioned known documents are directed to a resin composition containing only one of polycarbonate and polyester, and are intended to improve the impact resistance of the resin composition or to reduce the reduction in surface gloss due to the inclusion of a reinforcing agent.

JP-B-59-28223 discloses that a dispersed phase having a particle size of 0.01 to 1.0 μm, which may have an epoxy group, is adhered to a matrix composed of a polyester resin and a polycarbonate resin. Improve ductility and toughness by the dispersed phase of powder.

There is no disclosure or suggestion in the above-mentioned known publications about a technique for extinguishing the pearl luster of a molded article of a resin composition containing both an aromatic polycarbonate and an aromatic polyester.

 Hereinafter, the present invention will be further described with reference to examples.

EXAMPLES The aromatic polycarbonate (PC) used was a polycarbonate derived from bisphenol A and phosgene (trade name Lexan 131, Engineering Plastics Co., Ltd.).

The aromatic polyester is polybutylene terephthalate (PBT) (trademark Barox 310, Engineering Plastics Co., Ltd.).

As a glycidyl ester of an α-olefin and an α, β-unsaturated acid, an ethylene-glycidyl methacrylate copolymer was used. This has an ethylene content of about 89% and 3 g / 1
It has a 0 minute melt index (JIS K6760).

For comparison, an ethylene-ethyl acrylate copolymer (EEA, trademark NUC-6570, Nippon Unicar Co., Ltd.), an ethylene-vinyl acetate copolymer (EVA, trademark DPDJ-3269, Nippon Unicar Co., Ltd.), or a polyester elastomer ( Trademark, Lomod J10, Engineering Plastics Co., Ltd.).

Also, trisphenyl phosphite as a stabilizer,
0.2 parts by weight were used in each composition (not shown in Table 1).

 Carbon black was used as a coloring agent.

The components shown in Table 1 (parts by weight) were mixed with a Henschel mixer and extruded at 270 ° C. with a 65 mm single screw extruder to form pellets. The obtained pellets were dried in an oven at 120 ° C. for 4 hours and injection-molded at about 260 ° C. to prepare an Izod test piece and a 50 mm square plate (thickness: 3 mm). The 1/8 ″ Izod impact strength (notched) was measured according to ASTM D256. The pearl luster of the molded article was determined by visual observation of the surface of the square plate under natural light. The results are shown in Table 1.

Molded articles using EE, EVA or polyester elastomers exhibited intense pearl luster, but molded articles using the ethylene-glycidyl methacrylate copolymer according to the present invention have high impact strength and yet have pearl luster. Not shown.

Continuation of front page (56) References JP-A-63-61045 (JP, A) JP-A-62-184051 (JP, A) JP-A-60-173056 (JP, A) (58) Fields investigated (Int .Cl. ⁶ , DB name) C08L 69/00 C08L 67/02

Claims (1)

(57) [Claims] 1. A resin composition containing an aromatic polycarbonate and an aromatic polyester, wherein 0.5 to 15 parts by weight is based on 100 parts by weight of 30 to 80 parts by weight of the aromatic polycarbonate and 70 to 20 parts by weight of the aromatic polyester. Part of a resin composition containing a copolymer mainly comprising an α-olefin and a glycidyl ester of an α, β-unsaturated acid (provided that the composition is a butadiene-based copolymer and a methacrylic acid ester and an aromatic monovinyl compound). And a butadiene-based graft copolymer obtained by graft-copolymerizing one or more vinyl monomers selected from the group consisting of vinyl cyanide compounds, and
Ethylene and an α-olefin, an ethylene-based copolymer mainly containing an ethylenically unsaturated monomer or a diene monomer,
And a copolymer of ethylene and an unsaturated carboxylic acid ester).