JP2000191891A - Polyester elastomer resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester elastomer resin composition having a high oil resistance, grease resistance, heat aging resistance, resistance to flex fatigue when contacting a high-temperature grease, blow moldability and melt residence stability. SOLUTION: The titled composition is prepared by blending, against 100 pts.wt. polyether ester block copolymer, which essentially comprises a high- melting point crystalline polymer segment (a) mainly comprising a crystalline aromatic polyester unit and a low-melting point polymer segment (b) mainly comprising an aliphatic polyether unit, from 0.01 to 10 pts.wt. isocyanate compound having a functionality of 2 or larger and/or from 0.01 to 10 pts.wt. alkali or alkaline earth metal salt of a fatty acid, from 0.01 to 5 pts.wt. aromatic amine antioxidant, from 0.01 to 5 pts.wt. hindered phenol antioxidant, from 0.01 to 5 pts.wt. sulfur antioxidant and/or from 0,01 to 5 pts.wt. phosphorus antioxidant.

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, although the polyetherester block copolymer has the above-mentioned excellent properties, it has insufficient oil resistance, and when immersed in high-temperature oil for a long period of time, its 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.

[0007] In view of such circumstances, attempts have been made to improve the heat aging resistance and oil resistance of polyetherester block copolymers. For example, Japanese Patent Publication No. 46-38911 discloses this technique. Improved heat aging resistance of polyetherester block copolymer by blending hindered phenolic antioxidant and sulfur-based antioxidant and / or phosphorus-based antioxidant in polyetherester block copolymer A resin composition is disclosed.

[0008] 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.

Furthermore, Japanese Patent Application Laid-Open No. 58-23848 discloses a composition comprising a mixture of a polyester polyether block copolymer, a polyamide and an arylamine antioxidant, whose resistance to oxidative deterioration at high temperatures is significantly enhanced. , 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.

[0011] In addition, attempts to impart high melt viscosity to the polyetherester block copolymer include:
JP-A-52-121699 and JP-A-57-784.
No. 13, a resin composition obtained by reacting a polyetherester block copolymer with a polyisocyanate, and a polyetherester block copolymer disclosed in JP-A-61-111318 mixed with liquid diphenylmethane diisocyanate Resin composition,
Resin compositions obtained by mixing a metal salt of a carboxylic acid with a polyetherester block copolymer disclosed in JP-A-7-42728 can be exemplified. Also, JP-A-8-15
No. 1508 discloses a resin composition in which a polyetherester block copolymer is mixed with an aliphatic mono- or polycarboxylate having 10 to 40 carbon atoms, a diphenylamine-based compound, and a hindered phenol-based antioxidant. I have.

However, Japanese Patent Application Laid-Open No. 58-2384 describes the above.
No. 8, the resin composition disclosed in JP-A-8 No. 8 has certainly improved heat aging resistance. The resistance to lubricating oils represented by three oils has also been improved. However, 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. It does not have a melt viscosity, has insufficient melt stability, and has poor bending fatigue resistance. Further, Japanese Patent Application Laid-Open No. 2-173
The composition disclosed in Japanese Patent No. 059 is a composition having no bleed-out or yellowing on the surface of a molded article, and has improved heat aging resistance. However, it has insufficient oil resistance and grease resistance, does not have a melt viscosity suitable for blow molding, has insufficient melt stability, and has poor bending fatigue resistance. Furthermore, the composition disclosed in the above-mentioned JP-A-58-91758 is excellent in heat deterioration resistance and hydrolysis resistance,
Oil resistance and grease resistance are poor, and bending fatigue resistance is not sufficient. Furthermore, Japanese Patent Application Laid-Open Nos. 52-121699, 57-78413, and 61-1
The compositions disclosed in JP-A-11318, JP-A-57-42728 and JP-A-8-151508 certainly have high melt viscosities suitable for blow molding, and in particular, JP-A-8-151508. Although the composition disclosed in the gazette is excellent in bending fatigue resistance, it has insufficient heat aging resistance, oil resistance, and grease resistance, particularly, bending fatigue resistance when contacted with high-temperature grease.

[0013]

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

[0014] 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.

[0015]

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 isocyanate compound (B) and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C) with respect to 100 parts by weight of the combined (A). 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (D), 0.01 to 5 parts by weight of a hindered phenol-based antioxidant (E), and 0.01 of a sulfur-based antioxidant (F) To 5 parts by weight and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (G).

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
Bifunctional or higher isocyanate compound (B) 0.01 to 5
Parts by weight and / or 0.01 to 5 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of an aromatic amine antioxidant (D), and a polyamide resin (H) It is also characterized by comprising 0.1 to 20 parts by weight.

Further, the polyester elastomer resin composition of the present invention comprises a high melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low melting polymer segment mainly composed of aliphatic polyether units ( b) with respect to 100 parts by weight of the polyetherester block copolymer (A) containing
Bifunctional or higher isocyanate compound (B) 0.01 to 1
0 parts by weight and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of a hindered phenolic antioxidant (E), and sulfur-based antioxidant 0.01 to 5 parts by weight of an agent (F) and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (G) and 0.1 to 20 parts by weight of a polyamide resin (H). Also features.

Further, the polyester elastomer resin composition of the present invention comprises a high-melting crystalline polymer segment (a) mainly composed of crystalline aromatic polyester units and a low-melting polymer segment mainly composed of aliphatic polyether units (a). b) with respect to 100 parts by weight of the polyetherester block copolymer (A) containing
Bifunctional or higher isocyanate compound (B) 0.01 to 1
0 parts by weight and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of an aromatic amine antioxidant (D), and a hindered phenol type 0.01 to 5 parts by weight of an antioxidant (E), 0.01 to 5 parts by weight of a sulfur-based antioxidant (F) and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (G), Also characterized by the fact that 0.1 to 20 parts by weight of a polyamide resin (H) is blended.

The polyester elastomer resin composition of the present invention further comprises a high-melting crystalline polymer segment (a), which is a constituent component 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 difunctional or higher functional isocyanate compound (B) is diphenylmethane diisocyanate, and the alkali or alkaline earth metal salt (C) of the fatty acid is an aliphatic mono- or polycarboxylic acid having 10 to 40 carbon atoms. That the aromatic amine-based antioxidant (D) is a diphenylamine-based compound;
Hindered phenolic antioxidant (E) has a molecular weight of 50
0 or more hindered phenol compounds, sulfur antioxidant (F) is a thiodipropionate compound, phosphorus antioxidant (G) has a sulfur atom as well as a phosphorus atom in the molecule. A compound, wherein the phosphorus-based antioxidant (G) is a compound having two or more phosphorus atoms in a molecule, a polyamide resin (H)
Is a copolymerized polyamide resin, ASTM D-1
According to H.238, the melt viscosity index (MFR value) measured at a temperature of 250 ° C. under a load of 2160 g is 5 g / 10 min or less, used for blow molding, or a molding composition for flexible boots. Are also preferable conditions, and by applying these conditions, it is possible to expect to obtain a more excellent effect.

[0020]

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 point 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 polymer segment (b) in the polyetherester block copolymer (A) used in the present invention is preferably 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.

Examples of the difunctional or higher functional isocyanate compound (B) which is one of the components used in the resin composition of the present invention include tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, tolidine diisocyanate, naphthalene Diisocyanate, hexamethylene diisocyanate,
Examples include isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, and dicyclohexylmethane diisocyanate.
Among them, diphenylmethane diisocyanate is preferably used. The compounding amount of the bifunctional or higher functional isocyanate compound (B) is 0.01 to 10 parts by weight, preferably 0.05 to 8 parts by weight, more preferably 100 to 100 parts by weight of the polyetherester block copolymer (A). 0.1 ~
5 parts by weight. If the compounding amount is less than 0.01 part by weight, the effect is small, and if the compounding amount exceeds 10 parts by weight, gelation occurs due to stagnation of the melt during molding and molding cannot be performed.

Examples of the alkali or alkaline earth metal salt of a fatty acid (C) which is one of the components used in the resin composition of the present invention include decanoic acid, undecanoic acid, lauric acid, sebacic acid, myristic acid, Palmitic acid, stearic acid, linoleic acid, linolenic acid, oleic acid, dodecanecarboxylic acid, octadecylsuccinic acid,
Salts of sodium, potassium, lithium, barium, calcium, magnesium and the like such as octadecenylsuccinic acid, docosandicarboxylic acid, dimer acid and montan wax acid are included. Among them, an aliphatic mono- or polycarboxylate having 10 to 40 carbon atoms is preferably used. The amount of the alkali or alkaline earth metal salt of the fatty acid (C) is 0.01 to 10 parts by weight based on 100 parts by weight of the polyetherester block copolymer (A).
Preferably 0.05 to 8 parts by weight, more preferably 0.1 to 8 parts by weight.
1 to 5 parts by weight. If the compounding amount is less than 0.01 part by weight, the effect is small, and if the compounding amount exceeds 10 parts by weight, gelation occurs due to stagnation of the melt during molding and molding cannot be performed.

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

The phosphorus antioxidant (G) 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 these antioxidants (D) to (G) is 0.01 to 5 parts by weight, preferably 0.05 to 5 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.

The above (D) to (G) are the same as (D).
Type only, two types (E) / (F) or (E) / (G), three types (E) / (F) / (G), (D) / (E)
/ (F) or (D) / (E) / (G) and four types (E) / (E) / (F) / (G) must be combined and compounded. If even one component is missing from these combinations, the desired effect cannot be obtained.

The polyester elastomer resin composition of the present invention, when blended with a polyamide resin (H), can further provide an excellent polyetherester elastomer resin composition. The polyamide resin (H) used in the polyester elastomer resin composition of the present invention is a high molecular compound having an amide bond in a 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 polyamide resin (H) is used in an amount of 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 blending amount of the polyamide resin (H) is less than 0.1 part by weight, the degree of improvement of the desired 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 may 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 isocyanate compound and / or an aliphatic alkali or A raw material in which an alkaline earth metal salt and another predetermined antioxidant are blended, or a polyetherester block copolymer, a difunctional or higher functional isocyanate compound and / or an aliphatic alkali or alkaline earth metal salt, A method in which a raw material in which a predetermined antioxidant and a polyamide resin are blended is supplied to a screw-type extruder and melt-kneaded.Also, a screw-type extruder is first supplied with a polyetherester block copolymer and melted. Difunctional or more isocyanate compound and / or fat from the supply port of Of or alkali or alkaline earth metal salt, by supplying antioxidants and other formulations kneading, etc. Furthermore, the method of supplying kneading polyamide resin than other supply port, can be appropriately employed.

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.

[0040]

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 compositions and physical properties of A-1, A-2 and A-3.

[0048]

[Table 1] [Antioxidant] Table 2 shows abbreviations and structural formulas of the antioxidant used in the examples.

[0049]

[Table 2] [Production of polyamide resin] A copolymer (polyamide resin (H-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
A terpolymer (polyamide resin (H-2)) consisting of

Examples 1 to 6 The polyetherester block copolymers (A-1) and (A-
2) and (A-3), diphenylmethane diisocyanate (B-
1) Dry-blending sodium stearate (B-2) as an aliphatic alkali or alkaline earth metal salt, an antioxidant, and a polyamide resin at a compounding ratio shown in Table 3 and having a screw of 45 mmφ. Using a screw extruder, the mixture was melt-kneaded at a cylinder set temperature of 240 ° C. and then 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 tester Test temperature: 100 ° C. Distance between chucks: 25 mm ← 5.6 mm Flexing cycle: 300 times / min In this test, the smaller the generation of cracks, the better the durability. Excellent.

Next, using each pellet dried at 80 ° C. for 5 hours, the melt viscosity index (MFR value) was measured at 250 ° C. under a load of 2160 g according to ASTM D-1238.
In the case of a residence time of 5 minutes and a case of a residence time of 20 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 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 4 shows the evaluation results.

[0057]

[Table 3]

[Table 4] [Comparative Examples 1 to 9] Dry blending was performed at the compounding ratio shown in Table 3, and pelletization was performed in the same manner 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 4 shows the results.

As is evident from the results in Table 4, the polyetherester block copolymer had a difunctional or higher functional isocyanate compound, an aromatic amine-based antioxidant, a hindered phenol-based antioxidant, and a phosphorus-based antioxidant. A polyester elastomer resin composition of the present invention containing an antioxidant (Example 1) or a polyetherester block copolymer, an aliphatic alkali metal salt, an aromatic amine antioxidant, Polyester elastomer resin composition of the present invention blended with polyamide resin (Example 2),
Alternatively, a polyetherester block copolymer,
The polyester elastomer resin composition of the present invention comprising a difunctional or higher functional isocyanate compound or an aliphatic alkali metal salt, a hindered phenol antioxidant, a sulfur antioxidant or a phosphorus antioxidant, and a polyamide resin. Products (Examples 3 to 5) and the polyester elastomer resin composition of the present invention (Example 6) further blended with an aromatic amine-based antioxidant were all oil-resistant,
It has excellent grease resistance and heat aging resistance, and has excellent bending fatigue resistance even when it comes in contact 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 particularly have a resistance to bending fatigue when contacted with high-temperature grease, and It is inferior in maintaining the melt viscosity suitable for blow molding for a long time.

[0060]

As described above, the polyester elastomer resin composition of the present invention comprises a polyetherester block copolymer and a bifunctional or higher functional isocyanate compound and / or an aliphatic alkali or alkaline earth metal salt. , Aromatic amine antioxidants, hindered phenol antioxidants, sulfur antioxidants and / or
Or blending a phosphorus-based antioxidant, blending a polyetherester block copolymer with a bifunctional or more epoxy compound, an aromatic amine-based antioxidant, and a polyamide resin, or In the ether ester block copolymer, a polyamide resin, a difunctional or higher functional isocyanate compound and / or an aliphatic alkali or alkaline earth metal salt, a hindered phenol antioxidant, a sulfur antioxidant and / or By blending with a phosphorus-based antioxidant, and further blending an aromatic amine-based antioxidant,
It has excellent properties such as oil resistance, grease resistance, heat aging resistance, bending fatigue resistance when contacting with high temperature grease, blow moldability, and melt retention stability, especially constant velocity joint boots and rack and pinion boots. It is extremely useful as a molding material for automobile parts such as flexible boots and electric / electronic parts.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/49 C08K 5/49 C08L 75/04 C08L 75/04 F16J 15/52 F16J 15/52 A // B29C 49/00 B29C 49/00 (C08L 67/00 77:00) B29K 67:00 F-term (reference) 3J043 CB13 FA06 FB20 4F208 AA24 AA24F AA29 AA29E AB06 AG10 AR17 LB01 LG01 4J002 CF101 DH02 EG027 EG037 EJ019 EN068 EN068 EN068 EU198 EV029 EV049 EV059 EV149 EV249 EV259 EW04 EW06 FD078 FD079

Claims (18)

[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)
Functional or higher isocyanate compound (B) 0.01 to 10
Parts by weight and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (D), and hindered phenol-based oxidation 0.01-5 parts by weight of an antioxidant (E), 0.01-5 parts by weight of a sulfur-based antioxidant (F) and / or 0.01-5 parts by weight of a phosphorus-based antioxidant (G) A polyester elastomer resin composition comprising: 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)
0.01 to 5 parts by weight of a functional or higher isocyanate compound (B) and / or 0.01 to 5 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C) and an aromatic amine antioxidant (D) 0 A polyester elastomer resin composition comprising 0.11 to 5 parts by weight and 0.1 to 20 parts by weight of a polyamide resin (H). 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)
Functional or higher isocyanate compound (B) 0.01 to 10
Parts by weight and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of a hindered phenol-based antioxidant (E), and a sulfur-based antioxidant (F) A polyester elastomer obtained by mixing 0.01 to 5 parts by weight and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (G) and 0.1 to 20 parts by weight of a polyamide resin (H). Resin composition. 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)
Functional or higher isocyanate compound (B) 0.01 to 10
Parts by weight and / or 0.01 to 10 parts by weight of an alkali or alkaline earth metal salt of a fatty acid (C), 0.01 to 5 parts by weight of an aromatic amine-based antioxidant (D), and hindered phenol-based oxidation 0.01 to 5 parts by weight of an antioxidant (E), 0.01 to 5 parts by weight of a sulfur-based antioxidant (F) and / or 0.01 to 5 parts by weight of a phosphorus-based antioxidant (G), and polyamide A polyester elastomer resin composition comprising 0.1 to 20 parts by weight of a resin (H). 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. Bifunctional or higher functional isocyanate compound (B)
Is a diphenylmethane diisocyanate, The polyester elastomer resin composition of any one of Claims 1-7 characterized by the above-mentioned. 9. The method according to claim 1, wherein the fatty acid alkali or alkaline earth metal salt (C) is an aliphatic mono- or polycarboxylate having 10 to 40 carbon atoms. The polyester elastomer resin composition according to the above. 10. The method according to claim 1, wherein said aromatic amine antioxidant (D) is a diphenylamine compound.
The polyester elastomer resin composition according to any one of the above. 11. The polyester elastomer resin composition according to claim 1, wherein the hindered phenolic antioxidant (E) is a hindered phenolic compound having a molecular weight of 500 or more. 12. A method according to claim 1, wherein said sulfur-based antioxidant (F) is a thiodipropionate compound.
The polyester elastomer resin composition according to any one of the above. 13. The polyester elastomer resin composition according to claim 1, wherein the phosphorus antioxidant (G) is a compound having a sulfur atom as well as a phosphorus atom in a molecule. 14. The phosphoric antioxidant (G) is a compound having two or more phosphorus atoms in a molecule.
14. The polyester elastomer resin composition according to any one of items 13 to 13. 15. The polyester elastomer resin composition according to claim 2, wherein the polyamide resin (H) is a copolymerized polyamide resin. 16. 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 15, wherein the FR value is 5 g / 10 minutes or less. 17. The method according to claim 1, which is used for blow molding.
7. The polyester elastomer resin composition according to any one of 6. 18. The polyester elastomer resin composition according to claim 1, which is a molding composition for a flexible boot.