JPH11323110A - Polyester elastomer resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester elastomer resin composition having a good oil resistance, grease resistance, heat aging characteristics, resistance to fatigue from flexing when in contact with a high-temperature grease, blow moldability and melt retention stability. SOLUTION: A polyester elastomer resin composition is prepared by mixing, against 100 pts.wt. polyether ester block copolymer (A) containing as principal structural components a high-melting crystalline polymer segment (a) mainly comprising crystalline aromatic polyester units and a low-melting polymer segment (b) mainly comprising aliphatic polyether units, from 0.01 to 10 pts.wt epoxy compound (B) with a functionality of two or larger, from 0.01 to 5 pts.wt. aromatic amine antioxidant (C), from 0.01 to 5 pts.wt. hindered phenol antioxidants (D), from 0.01 to 5 pts.wt. sulfur antioxidant and/or from 0.01 to 5 pts.wt. phosphorus antioxidants (F).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is excellent in heat aging resistance, oil resistance, grease resistance and bending fatigue resistance,
In particular, it has extremely excellent bending fatigue resistance when it comes in contact with high-temperature grease, has high melt viscosity and excellent melt viscosity stability that maintains the viscosity for a long time, and has good blow moldability, especially flexible boots. The present invention relates to a polyester elastomer resin composition suitable for use in molding.

[0002]

2. Description of the Related Art A polyetherester block copolymer having a crystalline aromatic polyester unit such as polybutylene terephthalate unit as a hard segment and an aliphatic polyether unit such as poly (alkylene oxide) glycol as a soft segment is known. Excellent in extrudability, injection moldability, high mechanical strength, rubber properties such as impact resistance, elastic recovery, flexibility, low and high temperature properties, water resistance, etc., and thermoplastic processing Because of its ease of use, applications are expanding to automotive parts, electric and electronic parts, fibers, films, and the like.

[0003] However, polyetherester block copolymers have the above-mentioned excellent properties, but have insufficient oil resistance. In particular, when immersed in high-temperature oil for a long period of time, the strength and elongation gradually decrease. Therefore, in applications where the oil comes into contact with high-temperature oil, its use is actually restricted.

Further, the polyetherester block copolymer has poor heat aging resistance due to its susceptibility to oxidative deterioration, and its strength and elongation are reduced in a relatively short time when used in a high-temperature atmosphere. Can no longer be used,
Because cracks occur on the surface of the molded product and the appearance deteriorates, in applications such as used in a high temperature atmosphere,
The fact is that its use is restricted.

Further, the polyetherester block copolymer obtains a sufficiently high melt viscosity when performing blow molding as well as extrusion molding and injection molding, and stabilizes the melt viscosity for a long time in the molten state. Since it is difficult to maintain, there is a problem that the blow moldability is poor.

In addition, flexible boots manufactured by blow molding require excellent bending fatigue resistance.
The polyetherester block copolymer alone could give only a blow molded product that did not have sufficient flex fatigue resistance.

In view of such circumstances, many and many attempts have been made to improve the heat aging resistance, oil resistance, melt stability and the like of polyetherester block copolymers. JP-A-38911 discloses a method of blending a hindered phenol-based antioxidant and a sulfur-based antioxidant and / or a phosphorus-based antioxidant with a polyetherester block copolymer to obtain a polyetherester block copolymer. A resin composition having improved heat aging resistance is disclosed. JP-A-48-89955 discloses a resin composition in which an arylamine-based antioxidant is blended with a polyetherester block copolymer to improve heat aging resistance.

Further, JP-A-58-23848 discloses a composition in which a mixture of a polyester polyether block copolymer, a polyamide and an arylamine antioxidant has remarkably enhanced resistance to oxidative deterioration at high temperatures. , ASTM No. It is disclosed that resistance to high temperature at 3 oil is also good.

Further, Japanese Patent Application Laid-Open No. 2-173059 discloses that a polyetherester block copolymer has a polyamide resin, a hindered phenolic antioxidant,
A resin composition containing a sulfur-based antioxidant and / or a phosphorus-based antioxidant is disclosed.
JP-A-91758 discloses a resin composition in which a polyetherester block copolymer is blended with a glycidyl ester compound to improve the heat aging resistance of the polyetherester block copolymer. Are disclosed.

[0010] In addition, JP-A-48-10049
No. 5 discloses an attempt to improve the melt stability of a polyetherester block copolymer by a resin composition obtained by reacting a polyetherester block copolymer with a polyepoxide having a functionality not less than about 2. The publication discloses that, when reacting a polyetherester block copolymer with a polyepoxide having a functionality of not less than about 2, prolonged stirring at high temperature in the presence of an epoxy catalyst, It is also disclosed that a resin composition modified by prolonged post-curing has a high melt viscosity and an improved flex life.

Still further, JP-A-49-13298 discloses a polyetherester block copolymer, a polyepoxide having a functionality of not less than about 2,
A resin composition having improved mechanical strength at high temperature, impact resistance at low temperature, and hydrolysis resistance by reacting an epoxy curing agent is disclosed.

The resin compositions disclosed in JP-B-46-38911 and JP-A-48-89955 are certainly resin compositions having improved heat aging resistance. It is hard to say enough, and it is hard to withstand aging under severe conditions. Also,
ASTM No. Resistance to lubricating oils represented by oil 3 is also insufficient.

Further, the resin composition disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 58-23848 has certainly improved heat aging resistance. Although the resin composition has improved resistance to lubricating oils represented by Oil No. 3, the ASTM No. It is not oil-resistant to low-viscosity lubricating oils such as oil 3, but is not sufficiently resistant to grease, which is a semi-solid lubricant containing high-grade lithium soap or molybdenum disulfide, and is suitable for blow molding. Since it does not have a melt viscosity, the melt stability is insufficient and the bending fatigue resistance is poor.

Further, the resin composition disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2-173059 is a composition having no bleed-out or yellowing on the surface of a molded article, and has certainly improved heat aging resistance. However, oil resistance and grease resistance are still inadequate, and because they do not have a melt viscosity suitable for blow molding, the melt stability is also insufficient,
The bending fatigue resistance is also poor.

Furthermore, the above-mentioned Japanese Patent Application Laid-Open No. 58-9175.
The resin composition disclosed in Japanese Patent Publication No. 8 is certainly excellent in heat deterioration resistance and hydrolysis resistance, but is not only inferior in oil resistance and grease resistance, but also has insufficient bending fatigue resistance.

In addition to the above, JP-A-48-100
Although the resin compositions disclosed in JP-A-495-495 and JP-A-49-13298 have certainly improved melt stability and mechanical strength at high temperatures, they increase the viscosity to a level at which blow molding is possible. However, since it is necessary to use an epoxy curing catalyst, stir at a high temperature for a long time, and perform post-curing for a long time, there is a problem that the process is uneconomical and the cost increases.

[0017]

SUMMARY OF THE INVENTION The present invention has been achieved as a result of studying to solve the problems in the prior art described above.

Accordingly, an object of the present invention is to provide heat aging resistance in a severe oxidizing atmosphere and ASTM No.
(3) Not only oil resistance to lubricating oil typified by 3 oils, but also excellent resistance to grease and bending fatigue resistance, especially bending fatigue resistance when high temperature grease comes in contact. A polyester elastomer resin that has a sufficiently high melt viscosity suitable for molding, has excellent melt viscosity stability that maintains the high viscosity for a long time, and has good blow moldability, and is particularly suitable for molding applications such as flexible boots. It is to provide a composition.

[0019]

In order to achieve the above object, the polyester elastomer resin composition of the present invention comprises:
A polyetherester block copolymer mainly composed of a high-melting crystalline polymer segment (a) mainly composed of a crystalline aromatic polyester unit and a low-melting polymer segment (b) mainly composed of an aliphatic polyether unit. 0.01 to 10 parts by weight of a bifunctional or more functional epoxy compound (B), 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (C), 100 parts by weight of the combined (A), and hindered 0.01 to 5 parts by weight of a phenolic antioxidant (D), 0.01 to 5 parts by weight of a sulfur-based antioxidant (E) and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (F) Is characterized by being blended.

Further, the polyester elastomer resin composition of the present invention comprises a high melting crystalline polymer segment (a) mainly composed of a crystalline aromatic polyester unit and a low melting polymer segment mainly composed of an aliphatic polyether unit (a). b) with respect to 100 parts by weight of the polyetherester block copolymer (A) containing
0.01 to 10 parts by weight of a bifunctional or higher epoxy compound (B), 0.01 to 5 parts by weight of an aromatic amine antioxidant (C), and 0.1 to 20 parts by weight of a polyamide resin (G). Is also characterized.

Further, the polyester elastomer resin composition of the present invention comprises a high melting point crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low melting point polymer segment mainly composed of aliphatic polyether units ( b) with respect to 100 parts by weight of the polyetherester block copolymer (A) containing
0.01 to 10 parts by weight of a bifunctional or higher epoxy compound (B) and 0.0 hindered phenolic antioxidant (D)
1 to 5 parts by weight, sulfur antioxidant (E) 0.01 to
5 parts by weight and / or phosphorus antioxidant (F) 0.0
It is also characterized by blending 1 to 5 parts by weight with 0.1 to 20 parts by weight of a polyamide resin (G).

Further, the polyester elastomer resin composition of the present invention comprises a high melting crystalline polymer segment (a) mainly composed of a crystalline aromatic polyester unit and a low melting polymer segment mainly composed of an aliphatic polyether unit ( b) with respect to 100 parts by weight of the polyetherester block copolymer (A) containing
Bifunctional or more epoxy compound (B) 0.01 to 10 parts by weight, aromatic amine antioxidant (C) 0.01 to 5 parts by weight, hindered phenolic antioxidant (D) 0.1 to 10 parts by weight.
01 to 5 parts by weight, and a sulfur-based antioxidant (E) 0.01
To 5 parts by weight and / or phosphorus antioxidant (F)
01 to 5 parts by weight, and polyamide resin (G) 0.1 to 20
It is also characterized by being blended with parts by weight.

The polyester elastomer resin composition of the present invention further comprises a high-melting crystalline polymer segment (a), which is a constituent of the polyetherester block copolymer (A), and a polybutylene terephthalate unit. Wherein the low-melting polymer segment (b), which is a component of the polyetherester block copolymer (A), comprises a poly (tetramethylene oxide) glycol unit and / or a poly (propylene oxide)
A copolymer of a low-melting polymer segment (b) in the polyester block copolymer (A) having a copolymerization amount of 10 to 8;
0% by weight, the bifunctional or higher epoxy compound (B) is a glycidyl ester compound, the aromatic amine antioxidant (C) is a diphenylamine compound, a hindered phenol antioxidant ( D)
Is a hindered phenol compound having a molecular weight of 500 or more, the sulfur-based antioxidant (E) is a thiodipropionate compound, and the phosphorus-based antioxidant (F) is a sulfur atom together with a phosphorus atom in the molecule. That the phosphorus-based antioxidant (F) is a compound having two or more phosphorus atoms in the molecule; that the polyamide resin (G) is a copolymerized polyamide resin;
According to STM D-1238, temperature 250 ° C, load 2
The melt viscosity index (MFR value) measured at 160 g was 5 g /
10 minutes or less, to be used for blow molding, to be a molding composition for flexible boots,
However, these are all preferable conditions, and by applying these conditions, it is possible to obtain more excellent effects.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The high-melting crystalline polymer segment (a) of the polyetherester block copolymer (A) used in the present invention is composed of a crystal formed from an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol. Aromatic polyester units, preferably polybutylene terephthalate units derived from terephthalic acid and / or dimethyl terephthalate and 1,4-butanediol, and terephthalic acid, isophthalic acid,
Phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4'-
Dicarboxylic acid, diphenoxyethane dicarboxylic acid, 5-
A dicarboxylic acid component such as sulfoisophthalic acid or an ester-forming derivative thereof, and a diol having a molecular weight of 300 or less, for example, 1,4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol , Aliphatic diols such as decamethylene glycol, alicyclic diols such as 1,4-cyclohexanedimethanol and tricyclodecane dimethylol, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane 2,2-bis [4- (2-hydroxyethoxy) phenyl] propane, bis [4- (2-hydroxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane 4,4'-dihydroxy -p
Polyester derived from aromatic diols such as -terphenyl and 4,4'-dihydroxy-p-quarterphenyl, or a copolymerized polyester unit in which two or more of these dicarboxylic acid components and diol components are used in combination. good. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, a polyfunctional oxyacid component, a polyfunctional hydroxy component and the like in a range of 5 mol% or less.

The low-melting polymer segment (b) of the polyester block copolymer (A) used in the present invention comprises an aliphatic polyether unit. Specific examples of the aliphatic polyether include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, a copolymer of ethylene oxide and propylene oxide, poly ( Propylene oxide)
Examples include an ethylene oxide addition polymer of glycol, and a copolymer of ethylene oxide and tetrahydrofuran. Among these aliphatic polyethers, poly (tetramethylene oxide) glycol, an ethylene oxide adduct of poly (propylene oxide) glycol, and the like are preferable because the resulting polyester block copolymer has excellent elastic properties. Further, the number average molecular weight of these low melting point polymer segments is preferably about 300 to 6000 in a copolymerized state.

The copolymerization amount of the low melting point polymer segment (b) in the polyetherester block copolymer (A) used in the present invention is preferably from 10 to 80% by weight,
More preferably, the content is 15 to 75% by weight.

The polyetherester block copolymer (A) used in the present invention can be produced by a known method. For example, a method of subjecting a lower alcohol diester of a dicarboxylic acid, an excessive amount of a low-molecular-weight glycol, and a low-melting polymer segment component to a transesterification reaction in the presence of a catalyst, and polycondensing the obtained reaction product. Alternatively, a dicarboxylic acid, an excess amount of glycol and a low melting polymer segment component are subjected to an esterification reaction in the presence of a catalyst, and the resulting reaction product is polycondensed. Further, any method such as a method in which a high-melting-point crystalline segment is prepared in advance, and a low-melting-point segment component is added thereto to randomize by transesterification, may be used.

Specific examples of the bifunctional or more functional epoxy compound (B) which is one of the components used in the polyester elastomer resin composition of the present invention include a bisphenol A type epoxy compound formed by a condensation reaction between bisphenol A and epichlorohydrin. Resin, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether,
Diglycidyl ether compounds of glycols such as dibromoneopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl Ethers, polyglycidyl ether compounds of polyols such as sorbitol polyglycidyl ether, diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl hexahydrophthalate, diglycidyl naphthalenedicarboxylate, bibenzo Acid diglycidyl ester, methyl terephthalic acid jig Sidyl ester, diglycidyl tetrahydrophthalate, diglycidyl cyclohexanedicarboxylate, diglycidyl adipic ester, diglycidyl succinate, diglycidyl sebacate, diglycidyl dodecane dicarboxylate, diglycidyl octadecane dicarboxylate, dimer Diglycidyl ester compounds of dicarboxylic acids such as acid diglycidyl ester; and polyglycidyl ester compounds of polycarboxylic acids such as trimellitic acid triglycidyl ester and pyromellitic acid tetraglycidyl ester. Among these, a bifunctional epoxy compound having two glycidyl groups in the compound is preferable. Glycidyl ester compounds are particularly preferred.

The compounding amount of such a bifunctional or higher epoxy compound (B) is 0.01 to 10 parts by weight, preferably 0.05 to 8 parts by weight, based on 100 parts by weight of the polyester block copolymer (A). Parts, more preferably 0.1
-5 parts by weight. Bifunctional or higher epoxy compound (C)
If the amount is less than 0.01 part by weight, the degree of improvement of the desired effect is small, and if the amount exceeds 10 parts by weight, gelation occurs due to molten stagnation during molding and molding cannot be performed, which is not preferable.

The polyester elastomer resin composition of the present invention basically does not use an epoxy curing catalyst. However, if necessary, an epoxy curing catalyst may be used together with a bifunctional or more epoxy compound (B). Examples of such an epoxy curing catalyst include an aliphatic polyamine, an aromatic polyamine, an alicyclic polyamine, an aromatic acid anhydride, a cyclic aliphatic acid anhydride, an imidazole compound, and a tertiary amine compound.

Specific examples of the aromatic amine antioxidant (C) which is one of the components used in the polyester elastomer resin composition of the present invention include phenylnaphthylamine, 4,4'-dimethoxydiphenylamine, 4,4 '
Examples thereof include -bis (α, α-dimethylbenzyl) diphenylamine and 4-isopropoxydiphenylamine. Of these, a diphenylamine compound is preferable.

Specific examples of the hindered phenolic antioxidant (D) which is one of the components used in the polyester elastomer resin composition of the present invention include 2,4-dimethyl-6-t-butylphenol, 6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, hydroxymethyl-2,6-di-t-butylphenol, 2,6-di-t-α-dimethylamino-p- Cresol, 2,5-di-t-butyl-4-ethylphenol, 4,4′-bis (2,6-di-t-butylphenol), 2,2′-methylene-bis-4-methyl-6 −
t-butylphenol, 2,2′-methylene-bis (4
-Ethyl-6-t-butylphenol), 4,4'-methylene-bis (6-t-butyl-o-cresol),
4,4'-methylene-bis (2,6-di-t-butylphenol), 2,2'-methylene-bis (4-methyl-
6-cyclohexylphenol), 4,4′-butylidene-bis (3-methyl-6-t-butylphenol),
4,4'-thiobis (6-t-butyl-3-methylphenol), bis (3-methyl-4-hydroxy-5-t
-Butylbenzyl) sulfide, 4,4′-thiobis (6-t-butyl-o-cresol), 2,2′-thiobis (4-methyl-6-t-butylphenol), 2,
6-bis (2'-hydroxy-3'-t-butyl-5 '
-Methylbenzyl) -4-methylphenol, 3,5-
Diethyl ester of di-t-butyl-4-hydroxybenzenesulfonic acid, 2,2'-dihydroxy-3,3 '
-Di (α-methylcyclohexyl) -5,5′-dimethyl-diphenylmethane, α-octadecyl-3 (3 ′,
5'-di-t-butyl-4'-hydroxyphenyl) propionate, 6- (hydroxy-3,5-di-t-butylanilino) -2,4-bis-octyl-thio-1,
3,5-triazine, hexamethylene glycol-bis [β- (3,5-di-t-butyl-4-hydroxyphenol) propionate], N, N′-hexamethylene-bis (3,5-di-t -Butyl-4-hydroxyhydrocinnamic acid amide), 2,2-thio [diethyl-bis-3
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], dioctadecyl ester of 3,5-di-t-butyl-4-hydroxybenzenephosphonic acid,
Tetrakis [methylene-3 (3,5-di-t-butyl-
4-hydroxyphenyl) propionate] methane,
1,3,5-trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene, 1,1,3-tris (2-methyl-4-hydroxy-5-di-t-butylphenyl) butane, tris (3
5-di-t-butyl-4-hydroxyphenyl) isocyanurate, and tris [β- (3,5-di-t-butyl-4hydroxyphenyl) propionyl-oxyethyl] isocyanurate. Among them, those having a molecular weight of 500 or more such as tetrakis [methylene-3 (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane are preferable.

The sulfur-based antioxidant (E), which is one of the components used in the polyester elastomer resin composition of the present invention, includes thioether-based, dithionate-based, mercaptobenzimidazole-based, thiocarbanilide-based, and thiodipropion-based. It is a compound containing sulfur such as ester type. Among them, thiodipropion ester-based compounds are preferable.

The phosphorus antioxidant (F), which is one of the components used in the polyester elastomer resin composition of the present invention, includes phosphoric acid, phosphorous acid, hypophosphorous acid derivatives, phenylphosphonic acid, polyphosphonate And dialkylpentaerythritol diphosphite and dialkylbisphenol A diphosphite. Among these, a compound having a sulfur atom together with a phosphorus atom in a molecule and a compound having two or more phosphorus atoms in a molecule are preferable.

The amount of each of the antioxidants (C) to (F) is 0.01 to 5 parts by weight, preferably 0.05 to 100 parts by weight, based on 100 parts by weight of the polyetherester block copolymer (A). To 3 parts by weight, more preferably 0.1 to 1 part by weight
Parts by weight. If the amount is less than 0.01 part by weight, the degree of improvement of the intended effect is small, and if the amount is more than 5 parts by weight, blooming occurs and the mechanical strength of the polyetherester block copolymer decreases, which is not preferable.

Note that the above (C) to (F) correspond to one of (C).
Type only, two types (D) / (E) or (D) / (F), three types (D) / (E) / (F), (C) / (D)
/ (E) or (C) / (D) / (F) and four types (C) / (D) / (E) / (F) must be combined and combined. If even one component is missing from these combinations, the desired effect cannot be obtained.

When the polyester elastomer resin composition of the present invention is blended with a polyamide resin (G), it can further be an excellent polyetherester elastomer resin composition. The polyamide resin (G) used in the polyester elastomer resin composition of the present invention is a high molecular compound having an amide bond in the molecular chain, and includes a polymer from lactam, adipic acid, sebacic acid, dodecanedioic acid and the like. And a polymer of a salt obtained by a reaction with ethylenediamine, hexamethylenediamine, metaxylenediamine, or the like, or a polymer from ω-aminocarboxylic acid. These may be copolymers or two or more different polymers may be used in combination. Among these polyamide resins, a higher effect can be obtained when a copolymerized polyamide resin is used.

The amount of the polyamide resin (G) is 0.1 to 20 parts by weight, preferably 0.3 to 10 parts by weight, more preferably 0 to 100 parts by weight, based on 100 parts by weight of the polyetherester block copolymer (A). 0.5 to 5 parts by weight. If the compounding amount of the polyamide resin (G) is less than 0.1 part by weight, the degree of improvement of the intended effect is small, and if it exceeds 20 parts by weight, the flexibility and rubbery properties inherent in the polyetherester block copolymer are obtained. It is not preferable because properties are impaired.

Various additives can be further added to the polyester elastomer resin composition of the present invention as long as the object of the present invention is not impaired. For example, molding auxiliaries such as known nucleating agents and lubricants, ultraviolet absorbers and hindered amine compounds such as light stabilizers, hydrolysis resistance improvers, coloring agents such as pigments and dyes, antistatic agents, conductive agents, and flame retardants , A reinforcing agent, a filler, a plasticizer, a release agent, and the like.

The method for producing the polyester elastomer resin composition of the present invention is not particularly limited. For example, a polyetherester block copolymer may be added to a bifunctional or higher functional epoxy compound and other predetermined antioxidants. A method in which a raw material obtained by mixing a polyetherester block copolymer with a raw material obtained by mixing a bifunctional or more functional epoxy compound, a predetermined antioxidant and a polyamide resin is supplied to a screw-type extruder and melt-kneaded. First, a polyetherester block copolymer is supplied to a mold extruder and melted, and then a bifunctional or more functional epoxy compound, antioxidant or other compound is supplied from another supply port and kneaded. And a method in which the polyamide resin is supplied and kneaded from the supply port.

The polyester elastomer resin composition of the present invention has a temperature of 250 according to ASTM D-1238.
° C, melt viscosity index (MFR) measured under a load of 2160 g
Value) is preferably 5 g / 10 min or less, particularly preferably 3 g / 10 min or less.

The polyester elastomer resin composition of the present invention thus constituted has rubber properties such as flexibility, resilience, and elastic recovery, and is excellent in heat aging resistance, oil resistance, and grease resistance. It has extremely good bending fatigue resistance, especially excellent bending fatigue resistance even when it comes in contact with high-temperature grease, and has high melt viscosity and excellent melt viscosity stability for maintaining the viscosity for a long time.

The polyester elastomer resin composition of the present invention has good blow moldability and is suitable for molding materials for automobile parts, electric / electronic parts, etc., including flexible boots such as constant velocity joint boots and rack and pinion boots. Is extremely useful.

[0045]

EXAMPLES The structure and effect of the present invention will be further described below with reference to examples. All percentages and parts in the examples are on a weight basis unless otherwise specified. The physical properties shown in Reference Examples were measured as follows.

[Relative viscosity] A 0.5% polymer solution using o-chlorophenol as a solvent was measured at 25 ° C.

[Melting point] Differential scanning calorimeter (Du Pont)
Using a DSC-910 (manufactured by Sharp Corporation), the peak temperature of the melting peak when heated at a rate of 10 ° C./min in a nitrogen gas atmosphere was measured.

[Hardness (Shore D scale)] JIS K
Measured according to -7215.

REFERENCE EXAMPLE [Production of polyetherester block copolymer (A-1)] 302 parts of terephthalic acid, 327 parts of 1,4-butanediol and poly (tetramethylene oxide) glycol having a number average molecular weight of about 1400 216 parts together with 0.15 part of titanium tetrabutoxide were charged into a reaction vessel equipped with a helical ribbon type stirring blade, and heated at 190 to 225 ° C. for 3 hours to carry out an esterification reaction while distilling reaction water out of the system. . Add "Irganox" 1010 to the reaction mixture.
After adding 0.75 parts of a hindered antioxidant (Ciba Geigy Co., Ltd.), the temperature was raised to 245 ° C., and then the pressure in the system was reduced to 0.2 mmHg over 50 minutes. For 2 hours and 45 minutes. The obtained polymer was discharged into water in the form of a strand, and cut into pellets.

[Production of polyetherester block copolymer (A-2)] 297 parts of dimethyl terephthalate,
243 parts of 1,4-butanediol and poly (tetramethylene oxide) glycol (number average molecular weight of about 200
0) 300 parts together with 0.15 part of titanium tetrabutoxide were charged into a reaction vessel equipped with a helical ribbon-type stirring blade, and heated at 210 ° C. for 2 hours to obtain a theoretical methanol amount of 9 parts.
5% of methanol was distilled out of the system. To the reaction mixture
After adding 0.75 parts of Irganox "1010,
The temperature was raised to 245 ° C., and then the pressure in the system was reduced to 0.2 mmHg over 50 minutes, and polymerization was carried out under these conditions for 2 hours and 20 minutes. The obtained polymer was discharged into water in the form of a strand, and cut into pellets.

[Production of polyetherester block copolymer (A-3)] 189 parts of dimethyl terephthalate,
160 parts of 1,4-butanediol, poly (propylene oxide) end-capped with ethylene oxide
Glycol (number average molecular weight about 2200, EO content 26.
8%) 297 parts together with 0.15 part of titanium tetrabutoxide and 3 parts of trimellitic anhydride were placed in a reaction vessel equipped with a helical ribbon-type stirring blade, and heated at 210 ° C. for 2 hours 30 minutes to obtain theoretical methanol. 95% methanol
Was distilled out of the system. After adding 0.75 parts of “Irganox” 1010 to the reaction mixture, the temperature was raised to 245 ° C., and the pressure in the system was raised to 0.2 mmHg over 50 minutes.
The polymerization was carried out for 1 hour and 50 minutes under the reduced pressure. The obtained polymer was discharged into water in the form of a strand, and cut into pellets.

Table 1 shows the composition and physical properties of A-1, A-2 and A-3.

[0053]

[Table 1] [Epoxy compound] Table 2 shows the abbreviations and structural formulas of the epoxy compounds used in the examples.

[0054]

[Table 2] [Antioxidant] Table 3 shows abbreviations and structural formulas of the antioxidants used in Examples.

[0055]

[Table 3] [Production of polyamide resin] A copolymer (polyamide resin (G-1)) having a composition ratio of polycaprolactam and polyhexamethylene adipamide of about 65/35, polycaprolactam, polyhexamethylene adipamide and polyhexamethylene adipamide The composition ratio of methylene sebacamide is about 45/35/20
(Polyamide resin (G-2)) consisting of

Examples 1 to 6 The polyetherester block copolymers (A-1) and (A-
2), (A-3), an epoxy compound antioxidant, and a polyamide resin were dry-blended at a compounding ratio as shown in Table 4, and a cylinder set temperature was determined using a twin-screw extruder having a 45 mmφ screw. After melt-kneading at 240 ° C., the mixture was pelletized. After drying these pellets at 80 ° C for 5 hours, at a molding temperature of 250 ° C and a mold temperature of 60 ° C,
It was injection molded into a JIS No. 2 dumbbell. The dumbbell was immersed in Showa Oil Co., Ltd.'s "Shoishi Sunlight Grease SW-2" (high-grade lithium soap grease) at 120 ° C., and the time required for the tensile elongation at break to drop to half the initial value was measured.

The injection molded dumbbell was aged in a hot air oven at 160 ° C., and the time required for the tensile elongation at break to fall to half of the initial value and the time required for the dumbbell to break when bent at 180 ° were measured.

Next, each pellet dried at 80 ° C. for 5 hours was press-molded at a temperature of 250 ° C. to have a thickness of 2 mm and a width of 20 mm.
mm test pieces were made. On one side of the central part of the test piece where bending occurs, "Morilex N" manufactured by Kyodo Yushi Co., Ltd.
o. 2 "(molybdenum disulfide mixed with high-grade lithium soap grease) and applied in a hot air oven at 120 ° C.
Aged for days. After the test piece was taken out of the hot air oven, the attached grease was wiped off, the bending fatigue resistance was tested under the following conditions, and the crack length after 500,000 bending cycles was measured.

Test conditions: Testing machine: Dematcher bending fatigue testing machine Test temperature: 100 ° C. Distance between chucks: 25 mm → 5.6 mm Flexing cycle: 300 times / min In this test, the smaller the crack occurrence, the more the durability Excellent.

Next, using each pellet dried at 80 ° C. for 5 hours, the melt viscosity index (MFR value) was measured according to ASTM D-1238 at a temperature of 250 ° C. and a load of 2160 g.
In this case, the residence time is 5 minutes and the residence time is 60 minutes.
The points were measured.

Further, each pellet dried with hot air at 80 ° C. for 5 hours was subjected to a press blow molding machine (SB, manufactured by Osberger).
E50 / 140) and cylinder temperature 230
Under a molding condition of 250 ° C., a nozzle temperature of 250 ° C. and a mold temperature of 30 ° C., a weight having a shape in which a large diameter portion and a small diameter portion are connected by a bellows portion having a thickness of 0.5 mm having five peaks and five valleys. Blow moldability was evaluated by attempting to mold into a 60 g flexible boot for constant velocity joints.

Table 5 shows the evaluation results.

[0063]

[Table 4]

[Table 5] [Comparative Examples 1 to 9] Dry blending was performed at the compounding ratios shown in Table 4 and pelletized as in Examples 1 to 6.
These pellets and the polyester block copolymers (A-1), (A-2), and (A-3) obtained in Reference Examples were injection-molded in the same manner as in Examples 1 to 6 to form dumbbells. It was evaluated similarly. Table 5 shows the results.

As is clear from the results in Table 5, the polyetherester block copolymer was obtained by adding a bifunctional or higher functional epoxy compound, an aromatic amine antioxidant, a hindered phenol antioxidant, and a phosphorus A polyester elastomer resin composition of the present invention containing an antioxidant (Example 1) or a polyetherester block copolymer, a bifunctional or higher functional epoxy compound, an aromatic amine antioxidant, The polyester elastomer resin composition of the present invention blended with a polyamide resin (Example 2) or a polyetherester block copolymer
The polyester elastomer resin composition of the present invention containing a functional or higher functional epoxy compound, a hindered phenol antioxidant, a sulfur antioxidant and / or a phosphorus antioxidant, and a polyamide resin (Examples 3 to 5). 5),
Polyester elastomer resin composition of the present invention further blended with an aromatic amine-based antioxidant (Example 6)
All have excellent oil resistance, grease resistance, and heat aging resistance, and have excellent bending fatigue resistance even when contacted with high-temperature grease. Further, it has a melt viscosity suitable for blow molding, and it is maintained for a long time.

On the other hand, the polyester elastomer resin compositions of Comparative Examples 1 to 9 which lack the conditions of the present invention do not satisfy all of the above-mentioned properties, and in particular, have resistance to bending fatigue when contacted with high-temperature grease, It is inferior in maintaining the melt viscosity suitable for blow molding for a long time.

[0066]

As described above, the polyester elastomer resin composition of the present invention comprises a polyetherester block copolymer, a bifunctional or higher functional epoxy compound, an aromatic amine-based antioxidant, and a hindered phenol. Blending a sulfur-based antioxidant with a sulfur-based antioxidant and / or a phosphorus-based antioxidant; a polyetherester block copolymer with a bifunctional or higher functional epoxy compound;
Blending an aromatic amine-based antioxidant and a polyamide resin, or a polyamide resin, a difunctional or higher functional epoxy compound, a hindered phenol-based antioxidant, and sulfur in a polyetherester block copolymer. Oil resistance, grease resistance, heat aging resistance, and high temperature grease contact by blending an antioxidant and / or a phosphorus antioxidant with an aromatic amine antioxidant. Flex fatigue resistance,
It has excellent blow moldability and melt retention stability, and is extremely useful as a molding material for automotive parts such as flexible boots such as constant velocity joint boots and rack and pinion boots, and electric and electronic parts. Useful.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI (C08L 67/02 77:00 63:00) (72) Inventor Riji Miyauchi 1-2-1, Sonoyama, Otsu City, Shiga Prefecture Toray・ DuPont Co., Ltd. Shiga Plant

Claims (17)

[Claims] 1. A polymer comprising, as main components, a high-melting crystalline polymer segment (a) mainly composed of a crystalline aromatic polyester unit and a low-melting polymer segment (b) mainly composed of an aliphatic polyether unit. 2 parts per 100 parts by weight of the ether ester block copolymer (A)
0.01 to 10 parts by weight of a functional or higher epoxy compound (B), 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (C), and 0.0 of a hindered phenol-based antioxidant (D)
1 to 5 parts by weight, sulfur antioxidant (E) 0.01 to
5 parts by weight and / or phosphorus antioxidant (F) 0.0
1 to 5 parts by weight of a polyester elastomer resin composition. 2. A polymer comprising, as main components, a high-melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low-melting polymer segment (b) mainly composed of aliphatic polyether units. 2 parts per 100 parts by weight of the ether ester block copolymer (A)
A functional or higher epoxy compound (B) 0.01 to 10 parts by weight, an aromatic amine antioxidant (C) 0.01 to 5 parts by weight, and a polyamide resin (G) 0.1 to 20 parts by weight. A polyester elastomer resin composition that is blended. 3. A polymer comprising, as main components, a high-melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low-melting polymer segment (b) mainly composed of aliphatic polyether units. 2 parts per 100 parts by weight of the ether ester block copolymer (A)
0.01 to 10 parts by weight of a functional or higher epoxy compound (B) and 0.01 hindered phenolic antioxidant (D)
-5 parts by weight, and sulfur-based antioxidant (E) 0.01-5
Parts by weight and / or phosphorus-based antioxidant (F) 0.01
A polyester elastomer resin composition, which comprises about 5 parts by weight and 0.1 to 20 parts by weight of a polyamide resin (G). 4. A polymer comprising, as main components, a high-melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low-melting polymer segment (b) mainly composed of aliphatic polyether units. 2 parts per 100 parts by weight of the ether ester block copolymer (A)
0.01 to 10 parts by weight of a functional or higher epoxy compound (B), 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (C), and 0.0 of a hindered phenol-based antioxidant (D)
1 to 5 parts by weight, sulfur antioxidant (E) 0.01 to
5 parts by weight and / or phosphorus antioxidant (F) 0.0
A polyester elastomer resin composition comprising 1 to 5 parts by weight and 0.1 to 20 parts by weight of a polyamide resin (G). 5. The high-melting crystalline polymer segment (a), which is a component of the polyetherester block copolymer (A), is composed of polybutylene terephthalate units. Item 10. The polyester elastomer resin composition according to item 1. 6. The low-melting polymer segment (b), which is a constituent component of the polyetherester block copolymer (A), comprises a poly (tetramethylene oxide) glycol unit and / or an ethylene oxide of poly (propylene oxide) glycol. The polyester elastomer resin composition according to any one of claims 1 to 5, comprising an addition polymer unit. 7. The polyester block copolymer (A)
The copolymerization amount of the low melting polymer segment (b) is 1
The polyester elastomer resin composition according to any one of claims 1 to 6, which is 0 to 80% by weight. 8. The polyester elastomer resin composition according to claim 1, wherein the bifunctional or higher functional epoxy compound (B) is a glycidyl ester compound. 9. The polyester elastomer resin composition according to claim 1, wherein the aromatic amine antioxidant (C) is a diphenylamine compound. 10. The polyester elastomer resin composition according to claim 1, wherein the hindered phenolic antioxidant (D) is a hindered phenolic compound having a molecular weight of 500 or more. 11. The method according to claim 1, wherein said sulfur-based antioxidant (E) is a thiodipropionate compound.
The polyester elastomer resin composition according to any one of the above. 12. The polyester elastomer resin composition according to claim 1, wherein the phosphorus antioxidant (F) is a compound having a sulfur atom as well as a phosphorus atom in a molecule. 13. The phosphoric antioxidant (F) is a compound having two or more phosphorus atoms in a molecule.
13. The polyester elastomer resin composition according to any one of items 12 to 12. 14. The polyester elastomer resin composition according to claim 2, wherein the polyamide resin (G) is a copolymerized polyamide resin. 15. A melt viscosity index (M) measured at a temperature of 250 ° C. and a load of 2160 g according to ASTM D-1238.
The polyester elastomer resin composition according to any one of claims 1 to 14, wherein the (FR value) is 5 g / 10 minutes or less. 16. The method according to claim 1, which is used for blow molding.
6. The polyester elastomer resin composition according to any one of 5. 17. The polyester elastomer resin composition according to claim 1, which is a molding composition for a flexible boot.