JPS60130645A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:The titled composition exhibiting excellent low-temperature impact resistance, and good chemical resistance, appearance, and moldability, made by incorporating specified polymers into an aromatic polycarbonate resin. CONSTITUTION:The titled composition comprising 60-90wt% aromatic polycarbonate resin (A) (e.g. bisphenol A), 8-30wt% aromatic saturated polyester resin (B) (e.g. polyethylene terephthalate), 1-20wt% polyolefin (C) (e.g. PE), and 1.0- 20wt% component (D) consisting of 0.3-10wt% butadiene graft copolymer (a) and 0.3-10wt% acrylic ester graft copolymer (b). The combined addition of polymers B, C and D will eliminate the defects of resin A, such as poor moldability due to high melt viscosity, dependence of impact resistance on thickness, poor chemical resistance causing cracks when in contact with aromatic solvents or gasoline.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin composition that exhibits various mechanical properties, particularly excellent impact resistance at low temperatures, chemical resistance and appearance, as well as good moldability. In detail, A, aromatic polycarbonate resin 60 to 90 wt%, B, aromatic saturated polyester resin 8 to 30 wt%, and C,
Polyolefin 1-20% resistance and D, fil butadiene-based graph graft copolymer 0-10wt% and (2
) Acrylic acid ester graft copolymer 0.3 to 10
The total amount of both is 1.0 to 20i1t% within the range of ivt%.
This is a thermoplastic resin composition having excellent low-temperature impact resistance.

As is well known, aromatic polycarbonate resins are tough, have excellent impact resistance, electrical properties, and good dimensional stability, and are therefore widely used as useful engineering plastics. On the other hand, it has disadvantages such as high melt viscosity, poor moldability, thickness dependence of impact resistance, and poor chemical resistance such as cracking when it comes into contact with aromatic solvents or gasoline. As a result, the scope of its application is actually limited.

In order to improve these drawbacks, proposals have been made to blend various resins into aromatic polycarbonate resins. For example, Japanese Patent Publication No. 40-17663 discloses polyolefin, Japanese Patent Publication No. 40-24191 discloses ethylene-propylene copolymer, Japanese Patent Publication No. 38-15225 discloses AB
S resin, Japanese Patent Publication No. 39-71 teaches compounding Mon BS resin, and Japanese Patent Publication No. 48-29308 teaches compounding MAS resin, and these have improved moldability and impact resistance. However, there are various defects such as a decrease in heat deformation temperature, a surface peeling phenomenon due to poor compatibility, and weakness of the weld portion, and it cannot be said that the improvement is necessarily sufficient for practical use. In addition, in Japanese Patent Publication No. 36-14035,
There has been a proposal to improve solvent resistance by blending an aromatic polyester resin with an aromatic polycarbonate resin, but these resins have poor compatibility, the resulting composition has low impact resistance, and impact strength is dependent on thickness. No improvement has been achieved.

Furthermore, Japanese Patent Publication No. 39-20434 proposes a ternary composition containing an aromatic polycarbonate resin, an aromatic saturated polyester resin, and a polyolefin, and although the moldability and solvent resistance have been improved to some extent, However, this composition is inferior to the chemical resistance and impact resistance required in the market these days, and it also causes noticeable flow marks at the gate, resulting in poor product appearance and poor flow resistance when applied with paint. There is a drawback that the mark part is more likely to peel off than other parts.

The present inventors have developed a resin composition that has well-balanced molding processability of aromatic polycarbonate resin as well as various mechanical properties, thermal properties, chemical properties, etc. In particular, the thickness dependence of low-temperature impact resistance and impact strength The present inventors have discovered a quaternary thermoplastic resin composition that exhibits significant improvement in chemical resistance and significantly reduces or eliminates flow marks in the gate area, and has completed the present invention.

The present invention will be explained in detail below.

The aromatic polycarbonate resin of the present invention is an optionally branched thermoplastic polycarbonate polymer made by reacting an aromatic dihydroxy or a small amount of a polyhydroxy compound with a diester of phosgene or carbonic acid. An example of an aromatic dihydroxy compound is
2.2-bis(4-hydroxyphenyl)propane (bisphenol A), tetramethylbisphenol A1 tetrabromobisphenol A1 bis(4nordroxyphenyl)-P-diisopropylbenzene, hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, etc. In particular, bisphenol A is preferred. In addition, to obtain a branched aromatic polycarbonate resin, phloroglucin, 4,6-dimethyl-2.4.6-)li(4-hydroxyphenyl)hebutene-2,416-
cymethyl-2.4.6-)li(4-hydroxyphenyl)hebutane, 2,6-cymethyl-2.4.6-)
(4-hydroxyphenyl)hebutene-3,4,6
-Simethyl-2.4.6-tri(4-hydroxyphenyl)hebutane, 1°3.5-)li(4-hydroxyphenyl)benzene, 1.1. Polyhydroxy compounds exemplified by L-tri(4-hydroxyphenyl)ethane, and 3゜3-bis(4-hydroxyaryl)
Oxindole (= isatin bisphenol), 5-
Chlorisatin, 5,7-dichloroisatin, 5-bromiisatin, etc. are substituted with a polyhydroxy compound for a portion of the dihydroxy compound, for example 0.2 to 2 mol %. Furthermore, monoaromatic hydroxy compounds suitable for controlling the molecular weight include m- and p-methylphenol, tri- and p-propylphenol, p-bromophenol, p-bromophenol, p-
-tert~butylphenol and p-long chain alkyl-substituted phenol are preferred. Typical aromatic polycarbonate resins include polycarbonates whose main raw material is bis(4-hydroxyphenyl)alkane dihydroxy compounds, particularly bisphenol A, which can be obtained by using two or more aromatic dihydroxy compounds in combination. Branched polycarbonate obtained by using a small amount of a polycarbonate copolymer and a trivalent phenol compound can also be mentioned. The aromatic polycarbonate resin may be used as a mixture of 2M or more.

The aromatic saturated polyester resin used in the present invention is
It is a polymer obtained by reacting aromatic dicarboxylic acid or its diester with glycol or alkylene oxide by a known method. Specifically, the aromatic dicarboxylic acid has terephthalic acid or dimethyl terephthalate as the main component, Examples include polyethylene terephthalate and polytetramethylene terephthalate obtained by reacting this with ethylene glycol, butanediol, ethylene oxide, or the like. The aromatic saturated polyester resin may be a copolymer or may be used in the form of a mixture of two or more types. The aromatic saturated polyester resin used in the present invention has an intrinsic viscosity (intrinsic viscosity) of 0.8 or more, usually 1.0 or more, as measured at 30°C in a mixed solvent of phenol and tetrachloroethylene in a weight ratio of 6:4. 0
It is preferable to have a molecular weight of 1.5 to 1.5, and if it is less than 0.8, impact strength and chemical resistance will not be sufficiently improved.

The polyolefin of the present invention includes polyethylene, polypropylene, polybutene-1, poly-4-methylpentene, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-vinyl acetate copolymer, Ethylene-ethyl acrylate copolymer, etc., and those having a low glass transition temperature, −40° C. or lower, are particularly preferable.

The +11 butadiene-based graft copolymer used in the present invention is a combination of a butadiene-based rubbery polymer such as polybutadiene or butadiene-styrene copolymer, a methacrylic acid ester, an aromatic monovinyl compound, and a vinyl cyanide compound. One or more types of polymers are graft-polymerized by a method such as bulk polymerization, suspension polymerization, bulk suspension polymerization, solution polymerization, or emulsion polymerization, particularly by emulsion polymerization. Here, the amount of butadiene polymer used is 10 to 85% by weight,
It is preferably 30 to 70% by weight, and when the butadiene-based polymer is a copolymer, it is preferable to use a copolymer in which the butadiene component is 50% by weight or more.

If the amount used is less than 0% by weight, the resulting composition will have low induction shock resistance, and if it exceeds 85% by weight, the moldability of the resulting composition will be reduced, which is not preferred. Moreover, as the methacrylic acid ester, an alkyl ester having 1 to 4 carbon atoms, particularly methyl methacrylate, is preferable. Examples of the aromatic monovinyl compound include styrene, halogenated styrene, vinyltoluene, α-methylstyrene, and vinylnaphthalene, with styrene being particularly preferred. Examples of the vinyl cyanide compound include acrylonitrile, methacrylonitrile, and α-halogenated acrylonitrile, with acrylonitrile being particularly preferred.

The acrylic acid ester graft copolymer D used in the present invention (21) refers to an alkyl group having 2 to 12 carbon atoms.
A rubbery copolymer obtained by copolymerizing an alkyl ester of acrylic acid with a polyfunctional polymerizable monomer having a conjugated diene type double bond such as butadiene as an essential component, and a type of vinyl compound. Alternatively, it refers to a graft copolymer obtained by graft polymerization of two or more types as essential components. In addition to the above-mentioned butadiene, 1-methyl-
2-vinyl-4,6-hebutadien-1-ol, 7-
Methyl-3-methylene-1,6-octadiene, 1,3
．． 7-octatriene and the like can be mentioned. In addition, when copolymerizing an alkyl ester of acrylic acid with a polyfunctional polymerizable monomer having a conjugated diene type double bond, an aromatic vinyl compound such as styrene or methyl methacrylate may be used as desired. methacrylic acid ester, vinyl cyanide compound represented by acrylonitrile, vinyl ether compound represented by methyl vinyl ether, vinyl halide compound represented by vinyl chloride, and vinyl ester compound represented by vinyl acetate. A crosslinking agent typified by monofunctional polymerizable monomers, ethylene dimethacrylate, and divinylbenzene is appropriately selected and used. Vinyl compounds used in graft polymerization include methacrylic acid esters represented by methyl methacrylate, aromatic vinyl compounds represented by styrene, vinyl cyanide compounds represented by acrylonitrile, and halogenated vinyl compounds represented by vinyl chloride. Examples include polymerizable monomers selected from the group consisting of the following, and two or more of these may be used in combination. Furthermore, the above-mentioned crosslinking agent may be used in combination during graft polymerization.

In producing the acrylic acid ester-based graft copolymer, the polyfunctional polymerizable monomer having the conjugated diene type double bond is contained in the copolymer with the alkyl ester of acrylic acid in an amount of 0.1 to 10%. It is used in an amount accounting for % by weight.

A typical example is acrylic ester (e.g. n
-butyl acrylate, 2-ethylhexyl acrylate) and butadiene with a small amount of crosslinking agent (e.g. ethylene dimethacrylate, divinylbenzene) and optionally a methacrylic acid ester (e.g. methyl methacrylate).
are copolymerized by emulsion polymerization according to a conventional method, and styrene and styrene are added as graft component monomers to the obtained latex.
Graft copolymer obtained by adding a vinyl compound appropriately selected from methyl methacrylate, acrylonitrile, vinyl chloride, etc. and graft polymerizing according to a conventional method; acrylic ester (e.g., n-butyl acrylate, 2-
ethylhexyl acrylate) and compounds that have a non-conjugated double bond in addition to a conjugated diene type double bond in one molecule (e.g. Eva, 1-vinyl-2-vinyl-4,6-hebutadiene-
1-ol) and an ester of methacrylic acid as desired by a conventional method, adding a graft component i-mer to the obtained latex, and graft polymerizing according to a conventional method, such as a graft copolymer etc. It is.

These graft polymerizations may be carried out in one stage, or may be carried out in multiple stages by changing the components of the graft component monomer in multiple stages. Although a typical production example is shown using the emulsion polymerization method, it is a matter of course that the desired acrylic ester graft copolymer can be produced by other known polymerization methods as well. It is.

Such acrylic acid ester-based Graph 1 copolymer is available from Kureha Chemical Industry under the trade name "IIA-15", rHI
Resins commercially available as "A-28j or r I-11A-30" are preferably used.

To the above in the thermoplastic resin composition of the present invention.

Aromatic polycarbonate resin is 60 to 90 wt%, B,
Aromatic saturated polyester resin is 8 to 30 wt%, C, polyolefin 1 to 20 wt%, and D, +11 butadiene-based graft copolymer 0.3 to 10 wt% and (
2) Acrylic acid ester graft copolymer 0.3-1
The total amount of both is 1.0 to 2'Owt% in the range of 0.
Contains.

If the aromatic polycarbonate resin is less than 60 wt%, the heat resistance will not reach the level required for engineering plastics, and the dimensional stability will be poor, and if it exceeds 90 wt%, the improvement in moldability will be insufficient and the chemical resistance will deteriorate. It becomes insufficient. If the amount of aromatic saturated polyester resin is less than 8wt%, the improvement in chemical resistance will be insufficient, and 30w
Exceeding t% causes poor dimensional stability. Further, if the polyolefin content is less than 1 wt%, no improvement in chemical resistance or impact resistance will be achieved, and if it exceeds 20-t%, it will cause poor heat resistance. Furthermore, if the total amount of both the (11-butadiene-based graft copolymer and (2) acrylic acid ester-based graft copolymer) is less than 1 wt%, it is difficult to improve the flow marks at the gate portion.

The thermoplastic resin composition of the present invention as described above may contain various additives such as stabilizers, pigments, dyes, flame retardants, and lubricants, reinforcing materials such as inorganic or organic fiber substances, glass beads, etc., as desired. Various fillers may be blended, and other resin components may also be blended within a range that does not impair the characteristics of the present invention. For example, polycarbonate oligomers from bisphenol A or tetrabromobisphenol A can be used to improve moldability, flame retardancy, and surface properties, and heat-resistant polyesters such as polyester carbonates and polyarylates (e.g., trade names: U Polymer, Unitika@) For improving heat resistance, it is possible to incorporate

In preparing the thermoplastic resin composition of the present invention,
Any conventionally known method may be used, and methods of kneading using an extruder, Banbury mixer, rolls, etc. may be selected as appropriate.

Hereinafter, it will be explained by examples and comparative examples, but "%"
and "molecular weight" are based on weight unless otherwise specified.

Examples 1 and 2 and Comparative Examples 1 to 3 Aromatic polycarbonate resin made from bisphenol A (Mitsubishi Gas Chemical Company, trade name Newpiron 5-iooo, molecular weight 28,000), polyethylene terephthalate (Toyo Made by Boseki ■, product name: Univent RT-580, intrinsic viscosity 1.2 at 30°C, in a mixed solvent of phenol/tetrachlorethylene-6/4I ratio), polyethylene (
Manufactured by Mitsui Petrochemical @, product name: Hize Sox 7000F)
and butadiene-based graft copolymer (Japan Synthetic Rubber@
(product name: JSRMBS 67) and acrylic acid ester graft copolymer (manufactured by Ou Kagaku@, product name: Former A
-28) in the proportion shown in Table 1 in a blender, and
Mixed for a minute.

The resulting mixture was fed into a 404m vented extruder,
The mixture was melted and kneaded at a cylinder temperature of 260°C to form pellets. After drying the pellets in a hot air dryer at 120° C. for 5 hours or more, test pieces for measuring physical properties were molded by injection molding. The test results are shown in Table 1.

For comparison, aromatic polycarbonate resin alone (comparative example -
1), a composition of aromatic polycarbonate resin and polyethylene terephthalate (Comparative Example-2), a composition in which the butadiene-based graft copolymer and the acrylic acid ester-based graft copolymer were removed from the resin components of the example (Comparative Example-2); -3
), the physical properties were measured in the same manner as in the examples. The test results are shown in Table 1.

Examples 3 and 1 Comparative Example 4.5 In Examples 1 and 2, except for using ethylene-propylene copolymer (manufactured by Mitsui Petrochemical Sumikiku, trade name: Tafmer P-680) instead of polyethylene. Using the same resin components, they were mixed in the proportions shown in Table 1, pelletized using a vented extruder, and molded into test pieces for measuring physical properties in the same manner. The measurement results are shown in Table 1.

For comparison, the resin component of Example-3 excluding the butadiene-based graft copolymer and the acrylic acid ester-based graft copolymer (Comparative Example = 4), and the composition of Comparative Example-4 containing ethylene- Instead of propylene copolymer, use ethylene-propylene copolymer manufactured by Japan Synthetic Rubber ■, trade name: J
Table 1 also shows the results obtained using SREP 07C (Comparative Example-5) in the same manner as above.

Example 4 and Comparative Examples 6 and 7 In Examples 1 and 2, polytetramethylene terephthalate (Toyobo Sekibu, trade name: Toughpet N-1200, intrinsic viscosity 1.
2 at 30°C, a mixed solvent with a phenol/tetrachlorethylene-6/Awt ratio) was used, and the same resin components were used, mixed in the proportions shown in Table 1, and the cylinder temperature of the vented extruder was set at 250°C. A test piece for measuring physical properties was molded in the same manner except that. The measurement results are shown in Table 1.

For comparison, a resin composition of aromatic polycarbonate resin and polybutylene terephthalate (Comparative Example-6) and a butadiene-based graft copolymer and an acrylic acid ester-based graft copolymer were excluded from the resin components of Example-4. The same results as above were also obtained for the sample (Comparative Example-7).
Also listed in the table.

Example-5 and Comparative Example-8 In Example-4, ethylene was used instead of polyethylene.
A propylene copolymer (manufactured by Mitsui Petrochemical Co., Ltd., trade name: Tafuma-P-680) was used, using the same resin components and mixing in the proportions shown in Table 1 G, using a vented extruder. A test piece for measuring physical properties was formed using the same procedure.

The measurement results are shown in Table 1.

For comparison, Table 1 shows the results obtained in the same manner as above for the resin component of Example 5 excluding the butadiene-based graft copolymer and the acrylic acid ester-based graft copolymer (Comparative Example-8). Also listed.

Examples 6 and 7 The resin components used in Examples 1 to 5 were mixed in the proportions shown in Table 1, and test pieces for measuring physical properties were formed in the same manner as Examples 1 to 7. Physical properties were measured. The results are shown in Table 1.

Procedure (Hoshosho Seal) January 22, 1985 1, Indication of the case 1982 Patent Application No. 239080 2, Name of the invention Thermoplastic resin composition 3, Relationship with the amended person case (Patent (Applicant) 4. Subject of amendment 5. The following amendments will be made to the "Detailed description of the invention" column of the statement of contents of the amendment.

■Page 3, line 15 [Thickness dependence also corrects -1 to ``thickness dependence''.

■Page 19, line 7, 1 Examples-1 to 7”
1 to 5".

I-I Ni

Claims (1)

[Claims] A, aromatic polycarbonate resin 60 to 90 wt%,
B, aromatic saturated polyester resin 8-30wt%, C
, polyolefin 1-20iyt%, and D,
(11 butadiene-based graft copolymer 0.3-10wt
% and (2) acrylic acid ester graft copolymer 0
．． The total amount of both is 1.0 to 20 in the range of 3 to 10 wt%.
A thermoplastic resin composition having excellent low-temperature impact resistance, characterized in that it contains wt%.