JPS63301250A - Tough polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in impact resistance, heat resistance and chemical properties, by mixing a thermoplastic polyester with a specified resin mixture. CONSTITUTION:A resin mixture (B) is obtained by melt-mixing 100pts.wt. resin (a) having at least one epoxy group in the molecule and a bending modulus at room temperature <=10<4>kg/cm<2> [e.g., ethylene/glycidyl (meth)acrylate copolymer] with a copolymer (b) of an alpha-olefin with an alpha,beta-unsaturated carboxylic acid, in which at least 5mol.% of the carboxyl groups are neutralized with an alkali metal salt and which has a bending modulus at room temperature <=10<4>kg/cm<2> [e.g., ethylene/(meth)acrylic acid copolymer] and 0-66pts.wt. thermoplastic polyester (c) of an intrinsic viscosity of 0.35-1.20 at 150-300 deg.C. 100pts.wt. thermoplastic polyester (A) of an intrinsic viscosity of 0.35-1.20 is mixed with 5-100pts.wt. component B.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a novel tough polyester resin composition.

More specifically, the present invention relates to a thermoplastic polyester resin composition that provides a tough molded product with improved impact resistance.

[Prior art/problems to be solved by the invention] As a method of improving the impact resistance of thermoplastic resin molded products, a method of blending and modifying rubber-based substances has been generally adopted. Regarding thermoplastic polyester, which is one of the engineering plastics, a method of blending a rubber-based material is generally adopted for the purpose of improving impact resistance strength. Specifically, for example,
Examples include methods described in Japanese Patent Publication No. 7419 and Japanese Patent Publication No. 59-2822'a. However, in the method described above, the theory as to what kind of rubber-based substances are effective in improving impact resistance strength has not been sufficiently established, and experiments have been conducted using various combinations of thermoplastic polyester, rubber, and other substances. The reality is that we are searching for effective combinations.

In addition, blending high-performance engineering plastics with a rubber-based material with a relatively low modulus of elasticity improves impact resistance, but it also improves mechanical strength, heat resistance, chemical properties, and other properties expected of engineering plastics. There are two things that will not affect the performance.

[Means for Solving the Problems] The present invention was made to improve the impact strength of thermoplastic polyester without significantly reducing its excellent properties such as mechanical strength, heat resistance, and chemical properties. (a) 100 parts (by weight, same hereinafter) of thermoplastic polyester and a resin having at least one epoxy group in one molecule and having a bending modulus of elasticity at room temperature of 10' kg/cnl or less 100 parts, [2] A copolymer of an α-olefin and an α,β-unsaturated carboxylic acid, in which 5 mol% or more of the carboxyl groups contained in the copolymer are neutralized with an alkali metal salt. A tough polyester resin composition containing 5 to 100 parts of a copolymer having a flexural modulus of elasticity at room temperature of 104) cg/cj or less and 5 to 100 parts of a resin mixture obtained by melt-mixing 6 parts of thermoplastic polyester O to 6. relating to things.

[Example] The thermoplastic polyester as used herein refers to one containing at least 90 mol% of terephthalic acid or a derivative capable of forming an ester thereof as an acid component, and a glycol having 2 to 10 carbon atoms or a glycol thereof as a glycol component. A linear saturated polyethylene terephthalate resin obtained by using a polyethylene terephthalate resin containing at least 90 mol% of a derivative having ester-forming ability, a polyethylene terephthalate resin containing polyethylene terephthalate as a representative example, and polyethylene glycol, polypropylene glycol,
General formula (I): (wherein R1 is a divalent hydrocarbon group of 02 to C4, X is, for example, -〇(CH3)2-, -CH2''
, -8-1-3O2-, -Co- or other divalent bonding groups or direct bonds, m and n are each integers of 5 to 20, (m+n) R1s do not need to be the same) The concept includes a polyether compound having a unit of 1, a block copolymer with at least one derivative of the polyether compound, and further polybutylene terephthalate.

The acid components other than terephthalic acid and its derivatives having ester forming ability used in the range of less than 10 mol% include other aromatic dicarboxylic acids having 6 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 8 carbon atoms; , even carbon number 8-12
Specific examples include phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, adipic acid, sebacic acid, and cyclohexanedicarboxylic acid. etc. can be mentioned.

In addition, as the diol components other than glycol used in the range of less than 10 mol%, examples include aliphatic diols having 3 to 10 carbon atoms, alicyclic diols having 6 to 15 carbon atoms, and aromatic diols having 6 to 15 carbon atoms. Examples include propane-1,3-diol, butane-14-diol, pentane-1,5-diol, hexane-1,8-diol, cyclohexane-1, 4-dimethator, 2,2-dimethylpropane-
Examples include 1,3-diol, 2,2-bis(4°-hydroxycyclohexyl)propane, 2,2-bis(4′-hydroxyphenyl)propane, and hydroquinone.

Polyethylene terephthalate resin, which is one of the thermoplastic polyesters in the present invention and is produced from the above-mentioned components, usually has an intrinsic viscosity of 0.35 to 1.20 (phenol/tetrachloroethane-50,750 (weight ratio),
It has an intrinsic viscosity of 0.5% (wt%, the same applies hereinafter)/a degree, 25°C, the same applies hereinafter), but from the viewpoint of improving the balance between crystallization rate and mechanical strength, it has an intrinsic viscosity of 0.
40 to 0.70 is preferred, and 0.45 to 0.65
Particularly preferred.

The polyether unit contained in the block copolymer, which is another example of the thermoplastic polyester in the present invention, has the general formula (■): +R20+T-(■) (wherein, R2 has 2 to 18 carbon atoms). Divalent group, g is 5 to 4
(the integer of 0, the two R2s do not have to be the same) is a unit (excluding the terminal), and by containing this unit, the crystallization rate of the composition containing the block copolymer is increased. It can speed up the process and improve impact resistance.

Specific examples of R2 include ethylene, propylene, isopropylene, butylene, bisphenol A residue, etc. Among polyether compounds having a unit represented by general formula (1), polyethylene glycol, polypropylene glycol, and A block copolymer using one or more polyether compounds selected from tetramethylene glycol and polyether compounds having units represented by the general formula m has a high crystallization rate and is suitable for injection molding. This is preferable from the viewpoint of improved thermal stability.

The polyether compound contains 2 in a block copolymer component consisting of this polyether compound and a polyethylene terephthalate resin.
~90 parts, preferably 5 to 60 parts, particularly preferably 2
It is contained in an amount of 5 to 50 parts. If the amount is less than 2 parts, a sufficient effect of improving the crystallization rate cannot be expected, and if it exceeds 90 parts, the mechanical strength, moisture resistance, etc. of the molded article will be markedly reduced, which tends to be undesirable.

The block copolymer, which is one of the thermoplastic polyesters in the present invention produced from the above components, usually has an intrinsic viscosity of 0.35 to 1.20.
From the viewpoint of well improving the balance between crystallization rate and mechanical rate, those having an intrinsic viscosity of 0.40 to 1.00 are preferable, and those having an intrinsic viscosity of 0.50 to 0.80 are particularly preferable.

The block copolymer may be manufactured by copolymerizing in a polyester synthesis reaction vessel or by copolymerizing in an extruder.

The thermoplastic polyester may be used alone or in combination of two or more.

The resins used in the present invention that have at least one epoxy group in the molecule and have a flexural modulus of 104 kg/cIIi or less at room temperature (hereinafter referred to as resin ①) are epoxy groups, glycidyl ether groups, glycidyl ester groups, glycidyl A resin that has at least one epoxy group in its molecule, such as an epoxy group synthesized by the reaction of a compound having an amino group or a nitrogen-containing heterocycle with epichlorohydrin, and at the same time has a flexural modulus of 104 kg/crj or less. It is something.

Specific examples of the resin (2) include 01-C24 such as ethylene-glycidyl (meth)acrylate copolymer, ethyl acrylate-glycidyl (meth)acrylate copolymer, and butyl acrylate-allyl glycidyl ether copolymer. Copolymer of ester of alkyl alcohol and acrylic acid with glycidyl (meth)acrylate or allyl glycidyl ether, ethylene-allyl glycidyl ether copolymer, ethylene-glycidyl (meth)acrylate-vinyl acetate terpolymer, Ethylene-glycidyl (meth)acrylate copolymer 99-1
Copolymers in which 1 to 90% of methyl (meth)acrylate is grafted onto 0% methyl (meth)acrylate, polybutadiene epoxidized at both ends, epoxidized 1,2-polybutadiene, and the like.

Among these, particularly preferred are ethylene,
Copolymers of propylene, ■-butene, l-hexene, ■-octene, etc., or two or more of these, and glycidyl acrylate, glycidyl methacrylate, glycidyl cyclohexene-4-carboxylate, etc., or two or more of these, Examples include terpolymers in which vinyl acetate, methyl acrylate, methyl methacrylate, etc. are further included in the copolymer components.

The objective of the present invention, which is to improve impact resistance, can be achieved if there is one or more epoxy groups in the resin (2) in the molecule, but preferably 1 mol% or more (units constituting the resin) are present in the resin. Although it is preferable to have a certain amount (in terms of mass) from the viewpoint of improving the impact resistance when blended with a thermoplastic resin, if it exceeds 10 mol %, the impact strength of molded products from the composition of the present invention tends to decrease.

Note that the bending elastic modulus of the resin in ■ at room temperature is 104 k.
If it exceeds g/cj, the effect of improving impact resistance will be significantly reduced, which is not preferable.

A copolymer of an α-olefin and an α,β-unsaturated carboxylic acid according to the present invention, which is at least 5 mol%, preferably at least 30 mol%, particularly preferably at least 30 mol% of the carboxyl groups contained in the copolymer. More than 40 mol% is neutralized with alkali metal salt, and the flexural modulus at room temperature is 104 kgl.
A copolymer of less than cd (hereinafter referred to as a copolymer of 1) is a copolymer of at least one α-olefin such as ethylene, propylene, l-butene, 1-octene, or 1-hexene, and acrylic acid or methacrylic acid. , a copolymer with at least one α,β-unsaturated carboxylic acid such as maleic acid, in which 5 mol% or more of the carboxyl groups in the copolymer are neutralized with an alkali metal salt. , the content of α-olefin is preferably 50% or more.

The copolymer may further contain up to 25% of the copolymer, such as methyl acrylate, methyl methacrylate,
Other copolymerizable components such as butyl acrylate may also be copolymerized.

Preferred examples of the alkali metals forming the alkali metal salts in the copolymer (2) include sodium and potassium;
The toughness of the composition of the present invention is greatly improved by neutralizing more than 30 mol % of the carboxyl groups with the alkali metal salt, especially when 30 mol % or more of the carboxyl groups are neutralized with the sodium salt. This is particularly noticeable.

The flexural modulus of the copolymer (2) at room temperature is 10' in order to improve the impact strength of molded products made from the composition of the present invention.
It is necessary that it is 11 kg/ct or less.

In the present invention, 5 to 100 parts of copolymer (2), preferably 40 to 80 parts, particularly preferably 60 to 75 parts (60 to 75 parts) of copolymer (2) can be added to 100 parts of resin (2), and if necessary (thermoplastic polyester of ω component) A resin mixture of the above components is prepared by melt-mixing the components in a ratio of 86 parts or less. (2) Adding ingredients is preferable because it increases impact strength and produces less gel during processing.

The impact strength of molded products made from compositions in which the proportion of the copolymer in item (2) above is outside the range of 5 to 100 parts is not sufficiently improved, which is not preferable.

Furthermore, if the proportion of the thermoplastic polyester component (2) exceeds 66 parts, the impact strength will not be sufficiently improved.

In the resin mixture of component (b), each component is heated to 150'C~
Prepared by melt mixing at 300°C, preferably 170"C to 280"C. Especially with ■ resin and ■
If the temperature exceeds 250°C when melt-mixing the copolymer with the copolymer, it tends to gel, but even if the composition is manufactured using a gelled product, it will not be possible to produce a molded product with improved impact strength. It will be done.

5 to 10 parts, preferably 10 to 60 parts of the component (b) thus obtained (100 parts of the ω component and The composition of the present invention can be changed by melt mixing in a machine.

The blending amount of the +b+ component is (5 parts per 100 parts of the ω component)
If the amount is less than 100 parts, the effect of improving impact strength will not be sufficiently obtained, and if it exceeds 100 parts, the mechanical strength and heat resistance will be significantly reduced.

The composition of the present invention includes additives commonly used in resin compositions, such as stabilizers, colorants, antistatic agents, flame retardants,
Processability improvers, reinforcing materials such as glass fibers and carbon fibers, fillers such as talc, mica, glass peas, calcium carbonate, and the like may be appropriately blended.

Since molded products made from the composition of the present invention have good impact resistance,
It can be suitably used for housings of light electrical equipment, automobile parts, power tool bodies, etc.

Next, the composition of the present invention will be explained in more detail based on Examples and Comparative Examples.

The meanings of symbols used in Examples and Comparative Examples are as follows.

PET: 0.5 in a mixed solvent of phenol, 1.2.2-tetrachloroethane-50150 (weight ratio)
% concentration, polyethylene terephthalate with an intrinsic viscosity of 0.60 measured at 25°C.

PBT: East PBT 1401-XO7 (East ■
manufactured by).

MPET-1: Bisphenol A with an average molecular weight of 1000
1,2.2-tetrachloroethane-5015, which is obtained by copolymerizing the ethylene oxide addition polymer of bisphenol A by melt-kneading 30% of the ethylene oxide addition polymer of bisphenol A and 70% of polyethylene terephthalate oligomer under reduced pressure.
Modified polyethylene terephthalate with an intrinsic viscosity of 0.80 measured at 25°C in a mixed solvent of 0 (weight ratio).

MPET-2 20% of a block copolymer with an average molecular weight of 1300, in which 25% of polyethylene glycol is bonded to both ends of 5% of polypropylene glycol through ether bonds, and 80% of polyethylene terephthalate oligomer are melt-kneaded under reduced pressure. Phenol-1,2,2-tetrachloroethane-50150 (weight ratio) copolymerized with
A modified polyethylene terephthalate having an intrinsic viscosity of 0.60 as measured at 25°C in a mixed solvent.

EGMA: Ethylene-glycidyl methacrylate copolymer with a flow rate of 3.0 g/10 m1n according to ASTM D-1238E and a glycidyl methacrylate unit content of 10%.

BAAGE: Butyl acrylate-allyl glycidyl ether copolymer having a Mooney viscosity of 30 and an allyl glycidyl ether unit content of 4.5%.

EGMAVA: Terpolymer with 85% ethylene unit content, 10% glycidyl methacrylate unit content, 5% vinyl acetate unit content and 17 g/login according to ASTM D-1238.

EGMAGP: A resin obtained by graft copolymerizing 70 parts of a copolymer with an ethylene unit content of 85% and a glycidyl methacrylate unit content of 15% and 30 parts of methyl methacrylate.

EMANa-1: Old 1.0 g/10 m1n according to ASTM D-1288 with ethylene unit content 87%, methacrylic acid unit content 8.5%, sodium methacrylate unit content 6.5%
Random copolymer of.

EMANa-2: 2.8 g/10 m1n old random copolymer according to ASTM D-1238 with 86% ethylene unit content, 10% methacrylic acid unit content, and 4% sodium methacrylate unit content.

EAA: Random copolymer with ethylene unit content 9426, acrylic acid unit content 6%, old 5.0 g/10 m1n according to ASTM D-1238.

Examples 1 to 5 and Comparative Examples 1 to 3 Tetrakis[methylene-3 (3", 5°
-di-t-butyl-4°-hydroxyphenyl)probionate]methane 0.2 parts, tris(2,4-di-t-butyl)
-butylphenyl) phosphite and 0.4 part of pentaerythritol tetrakis (β-laurylthiopropionate) were added and mixed, and an extruder (
PCM-45) was used to perform kneading and extrusion at 280°C.

Total number of components of the resulting resin mixture (heaps in Table 1) +
0.8 parts) dried to a moisture content of 0.02% or less, the total number of parts of the PCM-45)
A resin composition was obtained by melt-kneading at 270°C. At this time, 30.0 parts of glass fiber (diameter 9.5 door, length 3 am) was added from the middle of the extruder.

The obtained resin composition was dried to a moisture content of 0.02% or less, and test pieces of 120X 120X 3■■ were prepared by injection molding, and the falling weight strength (load: 500 g) was prepared.

The tip radius (R 3/8 inch, semi-fracture height) was measured.

The results are shown in Table 1.

[Effect of the invention] Molded articles made from the composition of the present invention have excellent impact resistance ζ.

Claims (1)

[Scope of Claims] 1 (a) 100 parts by weight of thermoplastic polyester and (b) [1] Having at least one epoxy group in one molecule, and having a flexural modulus of elasticity at room temperature of 10^4 kg/cm^2
100 parts by weight of the following resin, [2] A copolymer of α-olefin and α,β-unsaturated carboxylic acid, in which 5 mol% or more of the carboxyl groups contained in the copolymer is an alkali metal salt. A resin mixture 5 to 100 parts by weight of a copolymer which is neutralized and has a flexural modulus of 10^4 kg/cm^2 or less at room temperature and [3] 0 to 66 parts by weight of a thermoplastic polyester. A tough polyester resin composition containing 100 parts by weight. 2. The composition according to claim 1, wherein the thermoplastic polyester is a polyethylene terephthalate resin. 3 Thermoplastic polyester is polyethylene terephthalate, polyethylene glycol, polypropylene glycol, general formula (I): ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1 is divalent carbonization of C_2 to C_4 hydrogen group,
A polyether compound having a unit represented by X is a divalent bonding group or a direct bond, m and n are each an integer of 5 to 20, and (m+n) R^1 do not need to be the same, and the polyether The composition according to claim 1, which is a block copolymer with at least one derivative of an ether compound. 4 The divalent bonding group is -C(CH_3)_2-, -C
The composition according to claim 3, which is H_2-, -S-, -SO_2-, -CO-. 5 A resin having at least one epoxy group in one molecule and having a flexural modulus of 10^4 kg/cm^2 or less at room temperature is ethylene-glycidyl (meth)acrylate copolymer, acrylate ester-glycidyl (meth) 2.) The composition according to claim 1, which is an acrylate copolymer or an acrylic acid ester-allyl glycidyl ether copolymer. 6 A patent in which the resin having at least one epoxy group in one molecule and having a flexural modulus of 10^4 kg/cm^2 or less at room temperature is an ethylene-glycidyl (meth)acrylate-vinyl acetate terpolymer A composition according to claim 1. 7 A resin having at least one epoxy group in one molecule and having a flexural modulus of 10^4 kg/cm^2 or less at room temperature is mixed with 99 to 10% by weight of ethylene-glycidyl (meth)acrylate copolymer (meth) ) Methyl acrylate 1~
The composition according to claim 1, wherein 90% by weight of the composition is graft copolymerized. 8 A copolymer of α-olefin and α,β-unsaturated carboxylic acid, in which 5 mol% or more of the carboxyl groups contained in the copolymer is neutralized with an alkali metal salt, and the flexural elasticity at room temperature is 2. The composition according to claim 1, wherein the copolymer having a copolymer ratio of 10^4 kg/cm^2 or less is an ethylene-(meth)acrylic acid copolymer. 9. The composition according to claim 8, wherein the alkali metal salt is a sodium salt or a potassium salt.