JPS6363743A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in moldability, tensile strength, bending strength, rigidity and impact resistance, by mixing a specified polyester-polyether block copolymer with a polycarbonate resin and a rubber- reinforced resin. CONSTITUTION:A terephthalic acid-based acid component, a 2-12C glycol component and a poly(oxyalkylene) glycol of an average MW of 400-6,000 are subjected to transesterification and polycondensation to obtain a polyester- polyether block copolymer (A) comprising 80-98wt% crystalline segments comprising aromatic polyester units and 20-2wt% segments comprising aliphatic polyether units. 30-84wt% component A is mixed with 15-50wt% polycarbonate resin (B) and 1-20wt% rubber-reinforced resin (C) (e.g., ABS resin) containing 40-80wt% rubber component comprising a conjugated diolefin polymer.

Description

[Detailed Description of the Invention] r! ? Field of Application] The present invention relates to thermoplastic resin Ml compositions, and more specifically, the present invention relates to thermoplastic resin Ml compositions, which have good molding processability and whose molded products have excellent tensile strength, bending strength, rigidity, and impact resistance. The present invention relates to a plastic resin composition.

[Prior Art] Among conventionally known thermoplastic resins, polyester-polyether block copolymers are resins with excellent fatigue resistance, wear resistance, impact resistance, etc.; There is a problem that strength and rigidity are low. In addition, polycarbonate resin is known for its impact resistance, heat resistance, and dimensional stability, but its impact resistance varies greatly depending on the shape (e.g., thickness) of the molded product of the resin. It has a good point. In addition, polycarbonate resins also have problems in molding processing because of their poor flow processing properties. Furthermore, there is also the problem of poor chemical resistance.

In order to solve the problems of conventional polyester-polyniter block copolymers and polycarbonate resins, Japanese Patent Publication No. 57-26538 discloses a polyester-polyniter block copolymer containing 20 to 80% by weight of polyalkylene gellicol units. A resin composition obtained by uniformly mixing a polyester-polyether block copolymer and a polycarbonate resin in a molten state is disclosed. However, in the case of this resin composition, the chemical resistance, tensile strength, bending strength, rigidity, etc. of the molded product obtained from it are not sufficiently improved depending on the blending ratio of the polycarbonate resin in the resin composition. It's hard to say.

Furthermore, JP-A-60-158251 discloses a method for improving the physical properties of the resin composition disclosed in JP-A-57-26538, in which polycarbonate resin, polyester-polyether block copolymer, and polyalkylene terephthalate are used. A resin composition obtained by uniformly mixing in a molten state is disclosed, but the molded product obtained from this resin composition also has a well-balanced tensile strength, bending strength, rigidity, and compatibility at a high level. I can't say that there is.

[Problems to be Solved by the Invention] The present invention solves the problem that conventional thermoplastic resins and resin compositions containing the same cannot provide molded products with excellent rigidity and impact resistance in a well-balanced manner. It is an object of the present invention to provide a thermoplastic resin composition which solves the problems and has good moldability and whose molded products have excellent tensile strength, bending strength, rigidity and impact resistance in a well-balanced manner.

[Means for Solving the Problems] The thermoplastic resin composition of the present invention comprises (I) a block consisting of (I) a crystalline segment A consisting of an aromatic polyester unit and a segment B consisting of an aliphatic polyether unit; Polyester-polyether block copolymers 30 to 84, which are copolymers in which the content of segment B in the copolymers is 20% by weight or less
% by weight, (II) 15 to 50% by weight of a polycarbonate resin, and (II) 1 to 20% by weight of a rubber reinforced resin containing 40 to 80% by weight of a rubber component consisting of a polymer of conjugated diolefin. do.

The present invention will be explained in detail below.

Segment A, which is a component of the polyester-polyether block copolymer of component (I) used in the present invention, is
It is a crystalline segment consisting of aromatic polynistyl units.

This segment) A is essentially a polyalkylene terephthalate unit derived from an acid component mainly consisting of terephthalic acid and a glycol component of a glycol having 2 to 12 carbon atoms, and this polyalkylene terephthalate unit is contained in segment A. a small amount of isophthalic acid as said acid component, preferably at least 80% by weight; 2.
Dicarboxylic acids such as 6-naphthalene dicarboxylic acid and adipic acid may be cocondensed and polymerized. The polyalkylene terephthalate unit is preferably a polyethylene terephthalate unit or a polytetramethylene terephthalate unit, and polytetramethylene terephthalate-1 position is particularly preferred.

Segment B, which is another component of the polyester-polyether block copolymer of component (I), is composed of aliphatic polyether units.

The components forming the aliphatic polyether unit of this segment) H include poly(oxyalkylene) glycols with an average molecular weight of 400 to 500, such as poly(ethylene oxide) glycol, poly(propylene oxide)
Examples include glycol, poly(tetramethylene oxide) glycol, and copolymers thereof, and poly(tetramethylene oxide) glycol is particularly preferred. If the average molecular weight is less than 400, the elastic function is lost, and if the average molecular weight exceeds 500 This is not preferable since the aliphatic polyether unit itself becomes crystalline and loses its elastic function.

The polyester-polyether block copolymer as component (I) is composed of segment A and segment B described above. Examples of the copolymer of component (I) include polyethylene terephthalate-poly(ethylene oxide) glycol block copolymer, polyethylene terephthalate-poly(tetramethylene oxide) glycol block copolymer, and polytetramethylene terephthalate-poly(tetramethylene oxide) glycol block copolymer. Examples include (ethylene oxide) glycol block copolymers and polytetramethylene terephthalate-poly(tetramethylene oxide) glycol block copolymers, with polytetramethylene terephthalate-poly(tetramethylene oxide) glycol block copolymers being particularly preferred. , these can be used alone or in combination. The content of segment B in the copolymer of component (I) must be 20% by weight or less. If the content of segment B exceeds 20% by weight, it is not preferable because the strength and rigidity of the molded product will decrease.The lower limit of the content of segment B is preferably 2% by weight.

The copolymer of component (I) comprises, for example, an aliphatic polyether providing segment B having a predetermined molecular weight;
Segment A can be produced by charging monomers to constitute segment A into a reaction vessel and then sequentially carrying out transesterification and polycondensation reactions in a conventional manner.

The content of the copolymer of component CI) in the resin composition is 30
-84% by weight, preferably 40-74% by weight. 3
If the content is less than 0% by weight, the impact properties of the molded product will be insufficient, and if the content exceeds 84% by weight, the strength and rigidity of the molded product will tend to decrease, which is not preferable.

Examples of the polycarbonate resin used as the (!tech) component in the present invention include polycarbonates mainly having structural units derived from aromatic bishydroxy compounds, such as bis-(4-hydroxyphenyl)-propane-2, Examples of polycarbonate resins include structural units derived from 2.

The content of the polycarbonate resin (I1) in the resin composition is 15 to 50% by weight, preferably 20 to 50% by weight. If the content is less than 15% by weight, the rigidity of the molded product of the composition will not be sufficient, and if the content exceeds 50% by weight, the solvent resistance will decrease, which is not preferable.

The component (I [ A rubber component made of a polymer is combined with a predetermined amount of a resin-forming monomer (see graph) 4. Examples of the rubber components constituting the component (■) include polybutadiene or butadiene-butyl acrylate copolymers containing 80% or more of units derived from butadiene as structural units, butadiene-styrene copolymers, and butadiene-acrylonitrile. Copolymers and the like can be mentioned. In addition, examples of resin-forming monomers to be graft-polymerized include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; styrene;
One or more types selected from aromatic vinyl compounds such as α-methylstyrene and vinyltoluene; acrylic acid alkyl esters, methacrylic acid alkyl esters, etc. can be mentioned.

The content of the rubber component in the component (II) is as described above, but preferably 40 to 70 c! It is 6. If the content of the rubber component is less than 40% by weight, it will be difficult to sufficiently improve the impact resistance of the molded product of the composition;
If it exceeds 0% by weight, it is not preferable because the rigidity of the molded product decreases.

The content of the rubber reinforced resin as component (III) in the resin composition is 1 to 20% by weight, preferably 1 to 10% by weight.

If the content is 1% by weight, the impact resistance of the molded product of the composition will be insufficient, and if it exceeds 20% by weight,
This is not preferable because the rigidity of the molded product decreases.

In addition to the above-mentioned CI) to (B) components, the composition of the present invention may optionally contain phenolic or subacidic compounds.
stabilizers; mold release agents such as ethylene bisstearamide, rice fatty acid esters and wax; ultraviolet absorbers; fillers; modifiers; dyes; pigments and flame retardants.

The composition of the present invention includes the above-mentioned components (I) to (III) and optionally other additives, such as a Panbali mixer,
It can be obtained by mixing using a heating roll or an extruder.

[Embodiments of the invention] Hereinafter, the present invention will be explained in further detail with reference to Examples.

In addition, in Examples and Comparative Examples, all "%" is based on weight, and evaluation of physical properties was performed by the following method.

#Impact resistance: According to ASTM D256, 23℃ and -
Notched Izot impact strength at 40°C was measured.

Stiffness: Flexural modulus at 23°C was measured according to ASTM 0790.

Examples 1 to 9 and Comparative Examples 1 to 18 Polynister-bolyether resin composition] Using dimethyl terephthalate, tetramethylene glycol, and polytetramethylene glycol having a number average molecular weight of 1,000 or 2.000. A block copolymer having a content ratio of segment A and segment B as shown in Table 1 was produced by the following method.

First, a predetermined amount of each of the above components was placed in a stainless steel transesterification reaction vessel equipped with a stirrer and a rectification column, and then heated while stirring. The temperature inside the container is 1
When the temperature reaches 50 to 160°C, tetra-n is added as a catalyst.
-Butyl titanate was added.Next, the methanol produced was distilled off while raising the temperature to 200°C over about 150 minutes to carry out the transesterification reaction, and when methanol had distilled out 97% or more of the theoretical distillation amount. The reaction was terminated.

The reaction product thus produced was placed in a stainless steel polymerization reaction vessel equipped with a vacuum device and a distillation system. After that, the temperature inside the polymerization reaction vessel was raised to 240°C, and the pressure of the reaction system was immediately reduced from normal pressure to 2 mmHg or less, and the reaction was continued in this state for about 3 hours to complete the polycondensation reaction. Then, the obtained reaction product was discharged, cooled, and cut to obtain a pellet-shaped polyester-polyether block copolymer.

As the component (I) constituting the composition of the present invention, the above-mentioned copolymer or a copolymer of polytetramethylene terephthalate and polytetramethylene glycol (Perubrene P70B and Velprene P40) are used. 1 [Product name, manufactured by Toyobo Construction; Both contain polytetramethylene glycol corresponding to segment B in an amount exceeding 20%; (II) Tubarex 7025A, which is a polycarbonate resin, as the component [Product name] ; using Mitsubishi Chemical Industries Co., Ltd.; (■) the first rubber-reinforced resin component
ABS resin having the monomer composition shown in the table was used. In addition to these, in Comparative Examples 10-18, polytetramethylene terephthalate ([η]=0.98 at 25° C. in a mixture of equal amounts of phenol and tetrachloroethane) was used.

The above components (I) to (In) were premixed in the proportions shown in Table 1 using a V-type blender. Then,
This mixture was melt-kneaded using a vented extruder with a screw diameter of 65 mm at a cylinder temperature of 250°C.
The resin composition of the present invention was obtained by shaping into pellets.

The resin composition thus obtained was injection molded using a 5 ounce injection molding machine with a screw diameter of 36 mm at a cylinder temperature of 270°C and a mold temperature of 80°C to achieve notched Izo impact strength. and test pieces for evaluation of flexural modulus were prepared.

Using this test piece, the notched Izot impact strength and flexural modulus were measured. The results are shown in Table 1.

As is clear from the results shown in Table 1, all test specimens prepared from the compositions of Examples were poor in both stiffness and impact resistance.

On the other hand, as in Comparative Example 1, when the content of segment B in the copolymer in component (I) exceeds 20%, the rigidity is inferior, and as in Comparative Examples 2 to 4, (II
) If the content of the rubber component in the rubber reinforced resin was less than 40%, the impact resistance was poor. Also, Comparative Examples 5 to 9
When a polyester-polyether block copolymer containing more than 20% of the component corresponding to segment B is combined with a polycarbonate resin, as in 1, the impact resistance is crushed, but the rigidity is low; Examples 10-1
When polyester-polyether block copolymers, polycarbonate resins, and polytetramethylene terephthalate containing more than 20% of the component corresponding to segment H as in 3 were combined, rigidity was excellent, but #impact It was inferior in gender. In general, when a polyester-polyniter block copolymer, polycarbonate resin, polytetramethylene terephthalate, and ABS resin containing a component corresponding to segment B in an amount exceeding 206% are combined as in Comparative Examples 14 to 18. had high rigidity, but poor impact resistance.

εEffects of the Invention As explained above, the thermoplastic resin composition of the present invention has good moldability and can be easily molded into a desired shape. In addition, the molded product is excellent in that it has both excellent rigidity and impact resistance in a well-balanced manner, and can be applied to other uses.

Claims (1)

[Scope of Claims] (I) A block copolymer consisting of a crystalline segment A consisting of an aromatic polyester unit and a segment B consisting of an aliphatic polyether unit, wherein the segment B in the copolymer Polyester-polyether block copolymer 30-8 having a content of 20% by weight or less
4% by weight, (II) 15 to 50% by weight of polycarbonate resin, and (II) a rubber component consisting of a polymer of conjugated diolefin.
A thermoplastic resin composition comprising 1 to 20% by weight of a rubber reinforced resin containing 0 to 80% by weight.