JP3376622B2 - Thermoplastic resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a thermoplastic resin which is excellent in compatibility and has improved delamination of a molded product, and at the same time has improved chemical resistance, impact resistance, molding processability and molding shrinkage. It relates to a composition.

[0002]

2. Description of the Related Art Acrylonitrile-styrene-butadiene copolymer resin (ABS resin) has excellent impact resistance and molding processability and is widely used as a general-purpose thermoplastic resin. However, chemical resistance is still insufficient, and there are problems such as cracking of molded products by various chemicals and surface roughness due to suction of paint, and the use is currently limited depending on the application.

On the other hand, an aromatic polyester resin (hereinafter abbreviated as polyester) generally has excellent chemical resistance, mechanical properties, electrical properties, heat resistance, low hygroscopicity, processability, etc., and is an engineering plastic. Widely used as.

Attempts have already been made to blend polyesters for the purpose of improving the chemical resistance of ABS resins. For example, JP-A-49-97081 and JP-A-61-183344 disclose blends of ABS resin and polybutylene terephthalate. Also,
JP-A-51-81848 discloses a graft copolymer,
A blend of polybutylene terephthalate and a thermoplastic elastomer is disclosed.

[0005]

However, although the chemical resistance is improved by these methods, the compatibility of both resins is still insufficient, and the excellent impact resistance which is an excellent characteristic of ABS resin is It does not develop sufficiently, or characteristics such as molding shrinkage change significantly with respect to ABS resin due to blending with a resin with high crystallinity, and in some cases it is necessary to renew the conventionally used mold.
It has the drawback that it is difficult to use the material as an extension of the resin.

An object of the present invention is to provide a resin composition having improved chemical resistance, which is a drawback of ABS resin, without impairing the excellent basic properties of ABS resin.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the ABS resin has excellent properties by blending the ABS resin with a specific aromatic polyester resin in a specific ratio. Further, they have found that a molded product which can improve chemical resistance without impairing impact resistance and molding shrinkage ratio and has excellent compatibility can be obtained without delamination, thereby reaching the present invention.

That is, the present invention relates to a diene rubber (A) 1
Vinyl cyanide (a) 10 in the presence of 0 to 85 parts by weight.
˜50% by weight, aromatic vinyl (b) 50 to 90% by weight,
Other copolymerizable vinyl monomer (c) 0 to 20% by weight
A graft copolymer obtained by graft-polymerizing 90 to 15 parts by weight of a monomer mixture (B) consisting of or a graft copolymer comprising the graft copolymer and a copolymer obtained by copolymerizing the remaining monomer. 50 to 95 parts by weight of the composition (a), 5 to 50 parts by weight of an aromatic polyester resin (b) in which the main dicarboxylic acid component is an aromatic dicarboxylic acid, and 10 to 90 mol% of the glycol component is cyclohexanedimethanol. The present invention provides a thermoplastic resin composition containing 1 to 50% by weight of the diene rubber (A) based on the total composition.

The present invention will be specifically described below.

The graft copolymer or the graft copolymer composition in the present invention means vinyl cyanide, aromatic vinyl, and, if necessary, all or part of other copolymerizable monomers of diene type. It is a composition of a graft copolymer and a copolymer graft-copolymerized with rubber.

Examples of the diene rubber include polybutadiene rubber, acrylonitrile-butadiene copolymer rubber, styrene-butadiene copolymer rubber, polyisoprene rubber and the like, and these may be used alone or in combination of two or more. . Especially polybutadiene rubber and /
Alternatively, a styrene-butadiene copolymer rubber is preferably used.

Examples of vinyl cyanide include acrylonitrile and methacrylonitrile.
Acrylonitrile is preferably used.

Examples of aromatic vinyl include styrene, α-methylstyrene, p-methylstyrene, pt-butylstyrene and the like. Among them, styrene and / or α-methylstyrene is preferably used.

As other copolymerizable monomers, methyl methacrylate, ethyl methacrylate, methacrylic acid-t-
Butyl, α-β-unsaturated carboxylic acid esters such as cyclohexyl methacrylate, unsaturated dicarboxylic acid anhydrides such as maleic anhydride and itaconic anhydride or derivatives thereof, N-phenylmaleimide, N-methylmaleimide, N- Examples thereof include imide compounds of unsaturated dicarboxylic acid such as t-butylmaleimide.

The composition ratio of the graft copolymer composition is not particularly limited, but the graft copolymer composition 100
From the viewpoint of moldability and impact resistance of the resulting thermoplastic resin composition, 10 to 85 parts by weight of diene rubber is preferable, and 15 to 75 parts by weight is more preferable, relative to parts by weight. The vinyl cyanide content is preferably 10 to 50 parts by weight, more preferably 12 to 45 parts by weight, and especially 15 to 40 parts by weight.
Parts by weight are preferred. 50-90 for aromatic vinyl
Part by weight is preferable, 55 to 88 parts by weight is more preferable, and 60 to 85 parts by weight is particularly preferable.
As the copolymerizable vinyl monomer other than the above, 0-2
It is preferably used in the range of 0 parts by weight.

The content of the diene rubber in the total thermoplastic resin composition is preferably in the range of 1 to 50% by weight, more preferably 3 to 45% by weight, and especially 5 to 40% by weight.
It is preferably in the range of. Diene rubber content is 5
If it exceeds 0% by weight, the rigidity of the resin composition is significantly impaired, which is not preferable. On the other hand, if it is less than 1% by weight, the impact resistance is poor.

There are no particular restrictions on the production of the graft copolymer composition, and commonly known methods such as bulk polymerization, solution polymerization, bulk suspension polymerization, suspension polymerization and emulsion polymerization can be used. It is also possible to obtain the above composition by blending copolymers which are (graft) copolymerized separately.

The polyester used in the present invention is a copolymer in which the main dicarboxylic acid component is an aromatic dicarboxylic acid and 10 to 90 mol% of the glycol component is derived from cyclohexanedimethanol.

The aromatic dicarboxylic acid constituting the polyester includes terephthalic acid, isophthalic acid, phthalic acid,
1,5-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,
2'-biphenyldicarboxylic acid, 3,3'-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid,
4,4'-diphenyl ether dicarboxylic acid, 4,4 '
-Diphenylmethane dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 4,4'-diphenyl isopropylidene dicarboxylic acid, 1,2-bis (phenoxy)
Ethane-4,4'-dicarboxylic acid, 2,5-anthracene dicarboxylic acid, 2,6-anthracene dicarboxylic acid,
4,4'-p-terphenylenedicarboxylic acid, 2,5-
Pyridine dicarboxylic acid and the like, terephthalic acid,
Isophthalic acid is particularly preferably used.

Two or more kinds of these aromatic dicarboxylic acids may be mixed. Incidentally, if a small amount, with these aromatic dicarboxylic acids, adipic acid, sebacic acid, dodecanedioic acid, aliphatic dicarboxylic acids such as azelaic acid,
One or more alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid can be mixed and used.

The diol components other than cyclohexanedimethanol include ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol,
2-Methyl-1,3-propanediol, diethylene glycol, triethylene glycol and the like can be mentioned. Ethylene glycol is particularly preferably used as a diol component other than cyclohexanedimethanol.

In the thermoplastic resin composition of the present invention, the blending ratio of the graft copolymer or the graft copolymer composition (a) and the aromatic polyester resin (b) is 50 to 95 parts by weight of (a), It is preferably 51 to 90 parts by weight, more preferably 55 to 85 parts by weight, and (b) is 5 to 5 parts by weight.
It is 0 parts by weight, preferably 10 to 49 parts by weight, more preferably 15 to 45 parts by weight, and the ratio is such that the total of (a) and (b) becomes 100 parts by weight. If (a) is less than 50 parts by weight, the molding processability such as excellent flowability of the ABS resin is impaired, and if (b) is less than 5 parts by weight, the ABS resin is ABS.
It is not preferable because the effect of improving the chemical resistance to the resin is small.

In the present invention, by using the vinyl copolymer having a functional group, the compatibility is further improved, the mechanical properties,
In particular, a thermoplastic resin composition having further improved impact strength can be obtained. The functional group-containing vinyl-based copolymer is a copolymer of aromatic vinyl, vinyl cyanide and / or another copolymerizable vinyl-based compound, which is further copolymerized with a vinyl-based monomer having a functional group. It is a copolymer obtained by.

Here, as the aromatic vinyl, styrene,
Examples thereof include α-methylstyrene, p-methylstyrene, pt-butylstyrene and the like. Of these, styrene and α-methylstyrene are preferable.

Examples of vinyl cyanide include acrylonitrile and methacrylonitrile. Of these, acrylonitrile is preferred.

As the vinyl-based monomer having a functional group,
Α, β-Unsaturated carboxylic acids such as acrylic acid and methacrylic acid, glycidyl esters of unsaturated organic acids such as glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylic acid and glycidyl itaconate, glycidyl ethers such as allyl glycidyl ether , Α, β-unsaturated carboxylic acid amides such as acrylamide and methacrylamide, and hydroxyl group-containing vinyl monomers such as 2-hydroxyethyl methacrylate. Of these, glycidyl acrylate and glycidyl methacrylate are preferably used. Further, these can be used alone or as a mixture of two or more kinds.

Other vinyl monomers which can be copolymerized include α, β-unsaturated carboxylic acid esters such as methyl methacrylate, ethyl methacrylate, t-butyl methacrylate and cyclohexyl methacrylate, and maleic acid. And unsaturated dicarboxylic acid anhydrides such as itaconic anhydride or derivatives thereof, imide compounds of unsaturated dicarboxylic acids such as N-phenylmaleimide, N-methylmaleimide, Nt-butylmaleimide and the like. Of these, methyl methacrylate is preferred.

The content of the functional group-containing vinyl copolymer of the present invention is not particularly limited, but the content of the functional group-containing vinyl monomer is usually from the viewpoint of impact resistance and fluidity of the resin. 1, (a) and (b)
It is preferable to select the compounding amount so as to be in the range of 0.01 to 30 parts by weight with respect to 00 parts by weight. If the amount is less than 0.01 parts by weight, the effect due to the addition is not observed, and if it exceeds 30 parts by weight, the moldability is deteriorated and the physical properties are deteriorated due to gelation, which is not preferable.

The method for producing the thermoplastic resin composition of the present invention is not particularly limited, and a generally known method can be adopted. That is, the graft copolymer or graft copolymer composition, 10 to 90 mol% of the glycol component
Is a cyclohexane dimethanol aromatic polyester resin and optionally modified vinyl copolymer pellets, powder, in the state of fine particles, granular state, etc. after uniform mixing using a high-speed stirrer, of sufficient kneading ability A method of melt-kneading with a certain single-screw or multi-screw extruder and a method of melt-kneading using a Banbury mixer or a rubber roll machine,
Various methods can be adopted.

The molding resin composition of the present invention comprises a graft copolymer or a graft copolymer composition, an aromatic polyester resin in which 10 to 90 mol% of the glycol component is cyclohexanedimethanol, and if necessary, Polystyrene, styrene / acrylonitrile copolymer, polymethylmethacrylate, styrene / methylmethacrylate / acrylonitrile copolymer, α-methylstyrene / styrene / acrylotolyl copolymer, α-methylstyrene / methylmethacrylate / acrylonitrile copolymer , P-methylstyrene / acrylonitrile copolymer, styrene / N
-Vinyl-based polymers such as phenylmaleimide copolymer, methyl methacrylate / butadiene / styrene terpolymer (MBS resin), AES resin, AAS resin, polycarbonate, polycaproamide (nylon 6), polyhexamethylene Adipamide (nylon 66), or other thermoplastic resin is appropriately mixed, polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / brene-1 copolymer, ethylene / propylene / cyclopentadiene copolymer, ethylene By appropriately mixing a polyolefin rubber such as / propylene / 5-ethylidene-2-norbornene copolymer, ethylene / vinyl acetate copolymer, ethylene / butyl acrylate copolymer,
It is also possible to adjust to more desirable physical properties and characteristics.

Depending on the purpose, reinforcing agents and fillers such as pigments and dyes, glass fibers, metal fibers, metal flakes, carbon fibers, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers and lubricants. , A plasticizer, an antistatic agent, a flame retardant and the like can also be added.

[0032]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples.

As an evaluation of impact resistance, 1/2 "Izod impact strength was measured according to ASTM D256-56. The lower limit of molding pressure is the lowest injection pressure required to fill a resin with a resin during injection molding. The chemical resistance was measured, and the results were compared.The chemical resistance was observed by visually observing the surface of the square plate by immersing the injection-molded square plate in methanol and gasoline for 24 hours at 23 ° C. The molding shrinkage ratio was ASTM D-955-. 5
It was measured according to 1. In addition, the following parts and% represent parts by weight and% by weight, respectively.

Reference example A graft copolymer was produced according to the following formulation.

A-1: 30 parts of polybutadiene latex (rubber particle diameter of about 0.28 μm, gel content of 80%) (as solid content), 70 parts of styrene 75%, acrylonitrile 25% of monomer, and emulsion polymerization method Graft-copolymerized by. The obtained graft copolymer was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to prepare a powdery graft copolymer (A-1). A-2: Polybutadiene latex (rubber particle diameter of about 0.
40 parts of a monomer consisting of 28 μm, gel content of 80% (60 parts) (as solid content), styrene of 75% and acrylonitrile of 25% was graft-copolymerized by an emulsion polymerization method. The obtained graft copolymer was coagulated with sulfuric acid, then neutralized with caustic soda, washed, filtered and dried to prepare a powdery graft copolymer (A-2). A-3: Polybutadiene latex (rubber particle diameter of about 0.
28 parts by weight (gel content 80%) 30 parts (as solid content), styrene 60%, acrylonitrile 25%, and methyl methacrylate 70 parts were graft-copolymerized by emulsion polymerization. The resulting graft copolymer was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to prepare a powdery graft copolymer (A-3).

B-1: An aromatic polyester resin comprising terephthalic acid as a dicarboxylic acid and 40 mol% of ethylene glycol and 60 mol% of 1,4-cyclohexanedimethanol as a diol component. B-2: An aromatic polyester resin comprising terephthalic acid as a dicarboxylic acid and 60 mol% of ethylene glycol and 40 mol% of 1,4-cyclohexanedimethanol as a diol component. B-3: Polybutylene terephthalate resin (Toray Industries, Inc.)
Manufactured by PBT-1200L).

C-1: 70 parts of styrene, 29 parts of acrylonitrile, and 1 part of glycidyl methacrylate were subjected to suspension polymerization to obtain a bead-shaped functional group-containing resin (C-1). C-2: 70 parts of styrene, 25 parts of acrylonitrile, and 5 parts of methacrylic acid were suspension-polymerized to obtain a bead-shaped functional group-containing resin (C-2).

D-1: 75 parts of styrene and 25 parts of acrylonitrile were subjected to suspension polymerization to give a bead-like copolymer (D-
1) was obtained.

Examples 1 to 12 Graft copolymer compositions A-1 and A- prepared in Reference Examples
2 and A-3, an aromatic polyester B-1 copolymerized with cyclohexanedimethanol as a glycol component,
B-2 and modified vinyl copolymer C-1, C-2 and copolymer D-3 were mixed in the mixing ratio shown in Table 1, and 40
Extruded by a mmφ extruder at an extrusion temperature of 250 ° C., pelletized, and then molded at a molding temperature of 2 for each pellet.
It was subjected to injection molding under the conditions of 60 ° C. and mold temperature of 60 ° C., each test piece was prepared, and the physical properties were evaluated.

Comparative Examples 1 to 5 Graft copolymers A-1 and A-2 produced in Reference Examples and aromatic polyesters B-1, B-2 and B-3 copolymerized with cyclohexanedimethanol as a glycol component. , Modified vinyl copolymer C-1 and copolymer D-
1 was mixed in the mixing ratio shown in Table 1, extruded by a 40 mmφ extruder at an extrusion temperature of 250 ° C., pelletized, and then each pellet was subjected to injection molding under the conditions of a molding temperature of 260 ° C. and a mold temperature of 60 ° C. It provided, each test piece was produced, and physical property evaluation was performed.

The following is clear from the examples and comparative examples. That is, the resin compositions obtained by the present invention are all excellent in moldability and chemical resistance, at the same time have good Izod impact strength, and have a molding shrinkage of AB.
It is almost equivalent to S resin. On the other hand, when the amount of the aromatic polyester in which 10 to 90 mol% of the glycol component is cyclohexanedimethanol is blended in excess of the composition disclosed in the present invention, the fluidity at the time of molding is increased as shown in the molding lower limit pressure. Property is deteriorated and the molding shrinkage is also poor. Further, the ABS resin alone has poor chemical resistance. on the other hand,
A system using a polybutylene terephthalate resin as the aromatic polyester has a drawback that the molding shrinkage is large.

[0042]

[Table 1]

[0043]

EFFECTS OF THE INVENTION The present invention is a thermoplastic resin composition which has improved compatibility and has improved delamination of molded articles, and at the same time improved chemical resistance, impact resistance, molding processability, and molding shrinkage. Regarding

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Claims (3)

(57) [Claims] 1. Copolymerizable in the presence of 10 to 85 parts by weight of diene rubber (A), 10 to 50% by weight of vinyl cyanide (a), 50 to 90% by weight of aromatic vinyl (b), and others. A graft copolymer obtained by graft-polymerizing 90 to 15 parts by weight of a monomer mixture (B) consisting of 0 to 20% by weight of a vinyl monomer (c), or the graft copolymer and the remaining monomer are copolymerized. 50 to 95 parts by weight of a graft copolymer composition (a) composed of a polymerized copolymer, a main dicarboxylic acid component is an aromatic dicarboxylic acid, and a glycol component of 10
Aromatic polyester resin (B) having 90 to 90 mol% of cyclohexanedimethanol (b) 5 to 50 parts by weight (however, the total of (a) and (b) is 100 parts by weight) A thermoplastic resin composition containing 1 to 50% by weight of a rubber (A). 2. A graft copolymer or a graft copolymer composition (a) 60 to 80 parts by weight and an aromatic polyester resin 20 to 40 parts by weight (however, the total of (a) and (b) is 100 parts by weight). The thermoplastic resin composition according to claim 1, which comprises: 3. The content of the vinyl monomer having a functional group is 0.01 to 30 parts by weight based on 100 parts by weight of the thermoplastic resin composition according to claim 1 or 2. A thermoplastic resin composition containing a functional group-containing vinyl copolymer.