JP2000212406A - Ester-based elastomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain excellent flexibility and mechanical characteristics, compression set in particular, at a high temperature by allowing an elastomer to contain crystalline aromatic polyester ingredients in its structure and have a specific storage elastic modulus. SOLUTION: An elastomer having a storage elastic modulus (23 deg.C) of 1×107-6×107 Pa and a storage elastic modulus (160 deg.C) of 2×106-5×107 Pa is provided. Concretely, is preferable a block copolymer of a polyester-based copolymer composed of 50-95 wt.% of a short chain component of formula I and 50-5 wt.% of a long chain component of formula II with a polyester composed of formula III linked together by an isocyanate component of formula IV or V. In the formulae, R0 is a 6-12C hydrocarbon; R1 and R3 are each a 2-8C alkylene; R2 is -R-O- having a number average mol.wt. of 500-5,000 (wherein R is a 2-8C alkylene); and R4 is a 2-15C alkylene, phenylene or a combination of methylene with phenylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ester-based elastomer which is excellent in flexibility and mechanical properties at a high temperature, particularly excellent in compression set at a high temperature.

[0002]

2. Description of the Related Art In recent years, due to increasing awareness of environmental issues,
The replacement of recyclable materials in various industrial fields is accelerating. As a rubber material, thermoplastic elastomer (TPE) has been attracting attention for a long time, and has been used in various applications in fields such as automobiles and various industries.

[0003] Among them, polyester-based elastomer (TPEE) is excellent in mechanical strength, heat resistance, abrasion resistance, flex fatigue resistance and the like, and is used in a wide range of industrial fields mainly in the automobile field. However, in TPEE,
There are drawbacks such as a higher hardness than ordinary rubber and lack of flexibility, a large compression set at large deformation and high temperature, and a lack of sag resistance. Improvements are desired.

When imparting flexibility to TPEE, it is necessary to reduce the proportion of hard segment components responsible for physical crosslinking, and such a method is disclosed in, for example, JP-A-2-88.
632 publication. However, there was a problem that the blockability of the hard segment component was reduced, and as a result, the melting point was lowered and the mechanical properties at high temperatures were lowered. A technique for improving sag resistance by increasing the degree of polymerization is disclosed in, for example, JP-A-52-121.
Although disclosed in Japanese Patent Application Laid-Open No. 699, there is a limit, and it is impossible to achieve both sag resistance and flexibility.

[0005]

DISCLOSURE OF THE INVENTION In view of the above, the present invention has a high blockability of a hard segment component and a soft segment component, and has excellent flexibility and mechanical properties at high temperatures, especially excellent compression set at high temperatures. An object is to provide an ester-based elastomer.

[0006]

The ester elastomer of the present invention has a crystalline aromatic polyester component in its structure and has a storage elastic modulus at 23 ° C. of 1 × 10 ^{7 to} 6 × 1.
0 ⁷ is Pa, and wherein the storage modulus in definitive to 160 ° C. is ^{2 × 10 6 ~5 × 10 7} Pa.

Hereinafter, the present invention will be described in detail.

[0008] The ester elastomer of the present invention is a thermoplastic elastomer having a crystalline aromatic polyester component as a hard segment, and the soft segment is not particularly limited.

[0009] The ester elastomer of the present invention comprises:
The storage elastic modulus at 1 ° C. is 1 × 10 ^{7 to} 6 × 10 ⁷ Pa, and the storage elastic modulus at 160 ° C. is 2 × 10 7
^{It is 6 to} 5 × 10 ⁷ Pa.

The storage elastic modulus at 23 ° C. is 1 × 1
If it is lower than 0 ⁷ Pa, sufficient mechanical strength cannot be obtained, and if it is higher than 6 × 10 ⁷ Pa, the flexibility becomes insufficient. Preferably from ^{2 × 10 7 ~5 × 10 7} Pa.
The storage elastic modulus at 160 ° C. is 2 × 10
Mechanical strength is lowered at a high temperature when ⁶ Pa becomes smaller than, a problem occurs in moldability becomes larger than 5 × 10 ⁷ Pa. Preferably, it is 5 × 10 ⁶ to 2 × 10 ⁷ Pa.

The above storage elastic modulus at 23 ° C. is 1 × 1
0 ⁷ be in the range of to 6 × 10 ⁷ Pa, when the storage elastic modulus at 160 ° C. is 2 × 10 ⁶ Pa less reduces the mechanical strength at high temperature, 5 × 10 ⁷ when Pa greater than A problem arises in moldability. On the other hand, even if the storage elastic modulus at 160 ° C. is in the range of 2 × 10 ^{6 to} 5 × 10 ⁷ Pa, if the storage elastic modulus at 23 ° C. is smaller than 1 × 10 ⁷ Pa, sufficient mechanical strength is obtained. When the pressure is higher than 6 × 10 ⁷ Pa, sufficient flexibility cannot be obtained. Therefore, 2
When the storage elastic modulus at 3 ° C. and 160 ° C. satisfies the above ranges, an ester-based elastomer excellent in both flexibility and mechanical strength at high temperatures is provided.

The above storage modulus is a value measured by a viscoelastic spectrometer (for example, “RSA-II” manufactured by Rheometric Scientific Effey). The storage elastic modulus is measured using a test piece having a thickness of 0.5 mm and a width of 3 mm, under the conditions of a measurement temperature of -100 to 200 ° C, a heating rate of 3 ° C / min, and a frequency of 1.6 Hz. .

The ester elastomer of the present invention is not particularly limited as long as it satisfies both the storage elastic modulus at 23 ° C. and the storage elastic modulus at 160 ° C.
For example, polyester-polyether copolymer elastomer, polyester-polylactone copolymer elastomer,
Polyester-polycarbonate copolymer elastomer,
Examples thereof include a polyester-polyester copolymer elastomer, and among them, a polyester-polyether copolymer elastomer is preferable.

The ester-based elastomer of the present invention is preferably constituted by repeating a short-chain polyester component represented by the general formula (1) and a long-chain polyester component represented by the general formula (2). 50 ingredients
Of a polyester-based copolymer (A) having a long-chain polyester component content of 50 to 5% by weight and a polyether (B) composed of a repeating unit represented by the general formula (3). An isocyanate component (C) which is a block copolymer, wherein the polyester copolymer (A) and the polyether (B) are represented by the general formula (4) or (5):
Are preferred.

The polyester-based copolymer (A) comprises a repeating short-chain polyester component represented by the general formula (1) and a long-chain polyester component represented by the general formula (2).

[0016] ^{-CO-R 0 -CO-O-} R 1 -O- ···· (1) -CO-R 0 -CO-O-R 2 - ···· (2)

In the formula, R ⁰ represents a divalent hydrocarbon group having 6 to 12 carbon atoms, R ¹ represents an alkylene group having 2 to 8 carbon atoms, and R ² represents —R—O— (in the formula, R represents an alkylene group having 2 to 8 carbon atoms) and a component having a number average molecular weight of 500 to 5000.

As the polyester-based copolymer (A), for example, known polyether elastomers obtained by reacting aromatic dicarboxylic acids and their ester-forming derivatives, low molecular weight diols and polyethers can be used. It is.

The aromatic dicarboxylic acid and its ester-forming derivative include, for example, terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, paraphenylenedicarboxylic acid, dimethyl terephthalate, dimethyl isophthalate, dimethyl orthophthalate, naphthalenedicarboxylic acid And dimethyl paraphenylenedicarboxylate. These may be used alone or in combination of two or more.

Examples of the low molecular weight diol include, for example,
Ethylene glycol, 1,2-propanediol, 1,
3-propanediol, 1,3-butanediol, 1,
4-butanediol, neopentyl glycol, 1,5
-Pentanediol, 1,6-hexanediol and the like, which may be used alone or in combination of two or more.

Examples of the polyether include polyethylene glycol, poly-1,3-propylene glycol, poly-1,2-propylene glycol, polytetramethylene glycol, polyhexamethylene glycol and the like. Among them, polytetramethylene glycol is preferred from the viewpoint of excellent mechanical properties and weather resistance, and commercially available products of polytetramethylene glycol include, for example, BA
"PTHF" manufactured by SF Co., Ltd., "PTMG" manufactured by Mitsubishi Kasei Co., Ltd., and the like.

The above polyether has a number average molecular weight of 500
It is preferable to use one having a number average molecular weight of 500 to 2,000. When the number average molecular weight is less than 500, the blocking property of the obtained polyester copolymer (A) is reduced, the melting point is reduced, and the mechanical strength of the ester elastomer at high temperature is reduced. If the number average molecular weight exceeds 5,000, the degree of polymerization of the ester elastomer does not increase due to low compatibility with the polyether (B) described below, and an ester elastomer having sufficient strength cannot be obtained.

As the soft segment of the polyester copolymer (A), an aliphatic polyether and / or an aliphatic polyester is preferred from the viewpoint of excellent flexibility and durability at low temperatures. Examples of the aliphatic polyether include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene glycol, and the like. Examples of the aliphatic polyester include polycaprolactone, polybutylene adipate, and the like.

The proportion of the short-chain polyester component in the components of the polyester copolymer (A) is 50 to 9
It is 5% by weight, preferably 70-90% by weight.
When the content of the short-chain polyester component is less than 50% by weight, the melting point of the polyester copolymer (A) is low, which adversely affects the mechanical strength of the ester elastomer at a high temperature. On the other hand, if the content exceeds 95% by weight, the compatibility with the polyether (B) described later is low, so that the degree of polymerization of the obtained ester elastomer does not increase, and a sufficient strength cannot be obtained.

The above polyester copolymer (A) can be polymerized by a known method. Specifically, the transesterification reaction is performed by heating the aromatic dicarboxylic acid and its ester-forming derivative together with the polyether and the excess low-molecular-weight diol to 200 ° C. in the presence of a catalyst,
Subsequently, a polyester-based copolymer (A) can be obtained by performing a polycondensation reaction at 240 ° C. under reduced pressure.

Polyether (B) used in the present invention
Is composed of repetitions represented by the general formula (3).
As such a polyether (B), for example, the same polyether as that constituting the polyester-based copolymer (A) is suitably used.

-R ³ -O- (3) In the formula, R ³ represents an alkylene group having 2 to 8 carbon atoms.

In order to obtain an ester-based elastomer linked by the isocyanate component (C), a polyester-based copolymer (A) and a polyether (B) are combined with a general formula OCN-R ⁴ -NCO (wherein R ⁴ has 2 to 15 carbon atoms
And a diisocyanate compound represented by the formula (1) in which an alkylene group, a phenylene group, or a methylene group is bonded to a phenylene group).

The above-mentioned polyester copolymer (A) and polyether (B) usually have a hydroxyl group at both ends, but may have a carboxyl group at a part of both ends. At this time, when both terminal functional groups reacting with the diisocyanate compound are hydroxyl groups, the isocyanate component (C) represented by the general formula (4) is used. When one is a hydroxyl group and the other is a carboxyl group, the general formula (5) is used. It is preferable to use the isocyanate component (C) represented by the formula (1).

[0030] ^{-O-CO-NH-R 4} -NH-CO-O- ··· (4) -CO-NH-R 4 -NH-CO-O- ··· (5) wherein, R ⁴ Represents an alkylene group having 2 to 15 carbon atoms, a phenylene group, or a combination of a methylene group and a phenylene group.

In the case where the terminal functional group of the polyester copolymer (A) is a carboxyl group, the compound represented by the general formula -CO-
NH-R ⁴ -NH-CO- (wherein, R ⁴ is a carbon number 2 to 1
5 shows an alkylene group, a phenylene group, or a methylene group and a phenylene group bonded to each other).

The structure of the diisocyanate compound is not particularly limited as long as it is a compound having two isocyanate groups in the same molecule, and three or more isocyanate groups within a range that maintains the fluidity of the produced ester elastomer. May be used.

Examples of the diisocyanate compound include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, and naphthalene diisocyanate; 1,2-ethylene diisocyanate, 1,3-
Propylene diisocyanate, 1,4-butane diisocyanate, 1,6-hexamethylene diisocyanate,
Examples include 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, isophorone diisocyanate, and aliphatic diisocyanates such as hydrogenated 4,4′-diphenylmethane diisocyanate.

The ester elastomer of the present invention can be obtained by melt-mixing the polyester copolymer (A), the polyether (B) and the isocyanate component (C). The amount of the polyether (B) is 50 to 50 parts by weight based on 100 parts by weight of the polyester copolymer (A).
The amount is preferably 0 parts by weight, more preferably 100 to 300 parts by weight. The amount of the isocyanate component (C) is preferably 10 to 100 parts by weight, more preferably 30 to 70 parts by weight, based on 100 parts by weight of the polyester copolymer (A).

When the amount of the polyether (B) is less than 50 parts by weight, the storage elastic modulus at 23 ° C. is 6 × 10 ⁷ Pa.
The ester elastomer did not have sufficient flexibility, and the storage elastic modulus at 160 ° C. was 5 × 10
^It becomes larger than ⁷ Pa, and the moldability decreases. When the amount of the polyether (B) exceeds 500 parts by weight,
The storage elastic modulus at 23 ° C. is smaller than 1 × 10 ⁷ Pa, and sufficient mechanical strength cannot be obtained.

If the amount of the isocyanate component (C) is less than 10 parts by weight, the ester elastomer does not become a high molecular weight substance, and the storage elastic modulus at 160 ° C. is 2 × 10 ^6.
It becomes smaller than Pa, and the mechanical strength at high temperature becomes low. Further, the storage elastic modulus at 23 ° C. may be smaller than 1 × 10 ⁷ Pa, and the mechanical strength may be reduced. Also,
If the amount of the isocyanate component (C) exceeds 100 parts by weight, the storage elastic modulus at 23 ° C. becomes larger than 6 × 10 ⁷ Pa, and the ester elastomer becomes inferior in flexibility.

An extruder can be used for the reaction between the polyester copolymer (A), polyether (B) and isocyanate component (C). When an extruder is used, the extrusion temperature is preferably 180 to 260 ° C, more preferably 2 to 260 ° C.
00-240 ° C. When the extrusion temperature is lower than 180 ° C., the reaction is difficult because the polyester copolymer (A) does not melt. When the extrusion temperature is higher than 260 ° C., the polyester copolymer (A) and the isocyanate component (C) are decomposed,
An ester elastomer having sufficient strength cannot be obtained.

The isocyanate compound (C) is preferably supplied after the mixture of the polyester copolymer (A) and the polyether (B) is melted and becomes uniform. Here, the uniform state refers to a state in which the molten mixture is transparent. Such a transparent state is at a temperature sufficiently higher than the melting point of the polyester-based copolymer (A), preferably at least 180 ° C, more preferably at 200 ° C.
The above is obtained by melting and mixing for 5 seconds or more.

In a mixing method other than the above, for example, a method of simultaneously supplying and mixing the polyester copolymer (A), the polyether (B) and the isocyanate compound (C), the methods (A), (B) and A heterogeneous reaction occurs due to the difference in the reactivity of (C), and an ester elastomer having sufficient mechanical strength cannot be obtained.

Also, a method of mixing the polyester copolymer (A) and the isocyanate compound (C) and then supplying and melt-mixing the polyether (B); a method of mixing the polyether (B) with the isocyanate compound (C); In the method in which the polyester-based copolymer (A) is supplied and melt-mixed after mixing with (C), an ester-based elastomer having a sufficient mechanical strength cannot be obtained.

The extruder is preferably a co-rotating twin-screw extruder or a co-rotating twin-screw extruder, more preferably a co-rotating intermeshing twin-screw extruder, in consideration of good stirring and mixing. It is. The control of the melt mixing temperature is as follows:
This can be done by setting the cylinder temperature of the extruder.

A catalyst can be used at the time of melt-mixing the polyester copolymer (A) and the polyether (B) with the diisocyanate compound (C). Examples of the catalyst include diacyl stannous, tetraacyl stannic, dibutyltin oxide, dibutyltin dilaurate,
Dimethyltin maleate, tin dioctanoate, tin tetraacetate, triethyleneamine, diethyleneamine, triethylamine, metal naphthenate, metal octylate, triisobutylaluminum, tetrabutyltitanate, calcium acetate, germanium dioxide, antimony trioxide, etc. These may be used alone or in combination of two or more.

A stabilizer may be used in the ester elastomer of the present invention.
3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene,
3,9-bis {2- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) -propionyloxy]-
Hindered phenolic antioxidants such as 1,1-dimethylethyl {-2,4,8,10-tetraoxaspiro [5,5] undecane; tris (2,4-di-t-butylphenyl) phosphite , Trilauryl phosphite, 2-
t-butyl-α- (3-t-butyl-4-hydroxyphenyl) -p-cumenylbis (p-nonylphenyl) phosphite, dimyristyl 3,3′-thiodipropionate, distearyl 3,3′-thio Examples thereof include heat stabilizers such as dipropionate, pentaerythryltetrakis (3-laurylthiopropionate), and ditridecyl 3,3′-thiodipropionate.

To the ester-based elastomer of the present invention, fibers, inorganic fillers, flame retardants, ultraviolet absorbers, antistatic agents, inorganic substances, higher fatty acid salts and the like are added to the extent that practicality is not impaired during or after production. An agent may be added.

Examples of the fibers include glass fibers,
Examples include inorganic fibers such as carbon fiber, boron fiber, silicon carbide fiber, alumina fiber, amorphous fiber, and silicon / titanium / carbon fiber; and organic fibers such as aramid fiber. Examples of the inorganic filler include calcium carbonate, titanium oxide, mica, and talc. Examples of the flame retardant include hexabromocyclododecane, tris- (2,3-dichloropropyl) phosphate, and pentabromophenyl allyl ether.

As the above-mentioned ultraviolet absorber, for example, p-
tert-butylphenyl salicylate, 2-hydroxy-
4-methoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,4,5-
Trihydroxybutyrophenone and the like.

Examples of the antistatic agent include N, N
-Bis (hydroxyethyl) alkylamine, alkylallyl sulfonate, alkyl sulfanate and the like. As the inorganic substance, for example, barium sulfate,
Alumina, silicon oxide and the like can be mentioned. Examples of the higher fatty acid salt include sodium stearate, barium stearate, sodium palmitate and the like.

The ester elastomer obtained in the present invention may be mixed with other thermoplastic resins and rubber components to modify its properties before use. As the thermoplastic resin, for example, polyolefin, modified polyolefin,
Examples include polystyrene, polyvinyl chloride, polyamide, polycarbonate, polysulfone, and polyester.

Examples of the rubber component include natural rubber, styrene-butadiene copolymer, polybutadiene,
Polyisoprene, acrylonitrile-butadiene copolymer, ethylene-propylene copolymer (EPM, EPD
M), polychloroprene, butyl rubber, acrylic rubber,
Examples thereof include silicone rubber, urethane rubber, olefin-based thermoplastic elastomer, styrene-based thermoplastic elastomer, PVC-based thermoplastic elastomer, ester-based thermoplastic elastomer, and amide-based thermoplastic elastomer.

The above-mentioned ester-based elastomer can be formed into a molded product by a generally used molding method such as press molding, extrusion molding, injection molding, blow molding and the like. The molding temperature varies depending on the melting point of the ester elastomer and the molding method, but is preferably from 160 to 280C. Molding temperature is 1
If the temperature is lower than 60 ° C, a uniform molded article cannot be obtained because the fluidity of the ester elastomer is low. If the temperature exceeds 280 ° C, the ester elastomer is decomposed and a molded article having sufficient strength cannot be obtained.

The molded article obtained by using the ester-based elastomer of the present invention is suitably used for, for example, automobile parts, electric / electronic parts, industrial parts, sports goods, medical goods and the like.

The above-mentioned automobile parts include, for example, boots such as constant velocity joint boots and rack and opinion boots; ball joint seals; safety belt parts;
Bumper fascia; emblem; mall, and the like. Examples of the electric / electronic parts include wire covering materials, gears, rubber switches, membrane switches, tact switches, O-rings, and the like. Examples of the industrial components include a hydraulic hose, a coil tube, a sealing material, a packing, a V-belt, a roll, a vibration damping material,
Shock absorbers, couplings, diaphragms, and the like.

Examples of the sporting goods include shoe soles and ball balls. Examples of the medical supplies include a medical tube, a blood transfusion pack,
Catheters and the like. Further, in addition to the above-mentioned uses, it can be suitably used as an elastic fiber, an elastic sheet, a composite sheet, a hot melt adhesive, a material for alloying with other resins, and the like.

[0054]

The conventional ester-based elastomer has been difficult to react because of insufficient compatibility of the constituent components. However, the ester-based elastomer of the present invention is a polyester-based copolymer (A) obtained by copolymerizing a short-chain polyester as a hard segment component with a polyether as a soft segment component, and a soft segment constituent component. It is presumed that the use of the polyether (B) improves the compatibility and improves the reactivity. As a result, an ester-based elastomer having a high blockability between the hard segment component and the soft segment component is obtained.

In the ester elastomer of the present invention, the crystal formed by the short-chain polyester component constitutes a cross-linking point, thereby exhibiting the properties as an elastomer. In particular, the above-mentioned ester-based elastomer is composed of a portion rich in a short-chain polyester component and a portion rich in a polyether component in a molecule, and has a shorter-chain polyester component than the conventional ester-based elastomer showing the same degree of flexibility. Is easily crystallized, so that a strong crosslinking point is formed. Further, the presence of the polyether component-rich portion increases the molecular weight between crosslinking points. As a result, the ester-based elastomer of the present invention can have a specific storage elastic modulus, become an elastomer having excellent flexibility and excellent mechanical properties at high temperatures.

[0056]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.

Preparation of Polyester Copolymer (A) 100 parts by weight of dimethyl terephthalate, 102 parts by weight of 1,4-butanediol, polytetramethylene glycol having a number average molecular weight of about 1,000 (“PTF1” manufactured by BASF)
000 "), 48 parts by weight, 0.3 parts by weight of tetrabutyl titanate as a catalyst, and 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4) as a stabilizer.
-Hydroxybenzyl) benzene 0.3 parts by weight, and
0.3 parts by weight of tris (2,4-di-t-butylphenyl) phosphite was added, and the reaction system was heated at 200 ° C. under nitrogen for 3 hours.
The transesterification reaction was performed while keeping the time. The progress of the transesterification reaction was confirmed by measuring the amount of methanol distilled off. After the transesterification proceeded, the temperature was raised to 240 ° C. for 20 minutes, and the pressure was reduced. The polymerization system is 20
Minutes, the degree of reduced pressure reached 2 mmHg or less. 20 in this state
As a result of performing the polycondensation reaction for 160 minutes, 160 parts by weight of a white polyester copolymer (A) was obtained.

Example 1 100 parts by weight of the polyester copolymer (A), polytetramethylene glycol (B) having a number average molecular weight of about 1000 (“PTF” manufactured by BASF)
H1000 ") 120 parts by weight and 4,4'-diphenylmethane diisocyanate (C) 40 parts by weight using a twin-screw extruder (L / D = 40, manufactured by Berstorf Co.), the cylinder temperature was all set to 220 ° C. The mixture was melt-mixed (residence time: 230 seconds) to obtain pellets of the ester elastomer. The resulting pellets are press-formed (press temperature 23
0 ° C.) to obtain a 2 mm thick ester-based elastomer sheet. The raw materials were supplied from the polyester copolymer (A) and the polytetramethylene glycol (B).
Was supplied from a raw material supply port of an extruder, and 4,4′-diphenylmethane diisocyanate (C) was supplied from an injection port provided in a fourth cylinder.

Example 2 Example 1 was repeated except that the amount of polytetramethylene glycol (B) was 100 parts by weight and the amount of 4,4'-diphenylmethane diisocyanate (C) was 30 parts by weight. Similarly, a 2 mm-thick ester-based elastomer sheet was obtained.

Example 3 Example 1 was repeated except that the amount of polytetramethylene glycol (B) used was 100 parts by weight and the amount of 4,4'-diphenylmethane diisocyanate (C) was 20 parts by weight. Similarly, a 2 mm-thick ester-based elastomer sheet was obtained.

Comparative Example 1 Dimethyl Terephthalate 100
Parts by weight, 102 parts by weight of 1,4-butanediol, 170 parts by weight of polytetramethylene glycol (B) having a number average molecular weight of about 1,000 ("PTH1000" manufactured by BASF), 0.3 parts by weight of tetrabutyl titanate as a catalyst 1,3,5-trimethyl-2,4,6 as a stabilizer
0.3 parts by weight of tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and tris (2,4
0.3 parts by weight of (-di-t-butylphenyl) phosphite was added, and the reaction system was maintained at 200 ° C. for 3 hours under nitrogen to carry out a transesterification reaction. The progress of the transesterification reaction was confirmed by measuring the amount of methanol distilled off. After the transesterification proceeded, the temperature was raised to 240 ° C. for 20 minutes, and the pressure was reduced. 2 mmH in 20 minutes
g or less. As a result of performing a polycondensation reaction in this state for 6 hours, 283 parts by weight of a white ester-based elastomer was obtained. The obtained ester-based elastomer was press-molded (press temperature 230 ° C.) to obtain 2 m
Thus, an ester elastomer sheet having a thickness of m was obtained.

Comparative Example 2 Polyester methylene glycol (B) having a number average molecular weight of about 1,000 (“PTF1000” manufactured by BASF) was used in the same manner as in Example 1 except that no polyester was used. Copolymer 11
0 parts by weight were obtained. 100 parts by weight of this polyester-based copolymer, polytetramethylene glycol (B) having a number average molecular weight of about 1,000 (“PFTF100” manufactured by BASF)
0 ") 110 parts by weight and 42 parts by weight of 4,4'-diphenylmethane diisocyanate (C) were all set to a cylinder temperature of 220 ° C. using a twin-screw extruder (L / D = 40 manufactured by Berstorf). Melt mixing (residence time 200
S), but pellets of the ester-based elastomer were not obtained.

Comparative Example 3 A 2 mm thick ester-based elastomer sheet was obtained by press-forming at 230 ° C. using “Hytrel 4047” manufactured by Dupont Toray as an ester-based elastomer.

Comparative Example 4 A 2 mm thick ester-based elastomer sheet was obtained by press-forming at 230 ° C. using “Hytrel 4275JB” manufactured by Du Pont-Toray as an ester-based elastomer.

The following items were evaluated for the ester-based elastomer sheets obtained in the above Examples and Comparative Examples.
The results are shown in Table 1. (1) Storage modulus Using a viscoelastic spectrometer “RSA-II” manufactured by Rheometric Scientific Effey, 23
C. and 160.degree. The storage elastic modulus was measured using a test piece having a thickness of 0.5 mm and a width of 3 mm, at a measurement temperature of −100 to 200 ° C., a heating rate of 3 ° C./min, a frequency of 1.6 Hz, and a strain of 0.001%. Was performed under the following conditions. (2) Glass transition temperature (Tg), melting point Differential scanning calorimeter (“D” manufactured by TA Instruments
SC2920 ”) at a heating rate of 10 ° C./min. (3) Surface hardness According to JIS K 6301, 23 ° C with A type spring
Was measured. (4) Tensile properties Tensile strength and tensile elongation at room temperature were measured according to JIS K6301. (5) Compression set The compression set was measured at 100 ° C with a compression set of 25% in accordance with JIS K6301.

[0066]

[Table 1]

The ester-based elastomer of the present invention has the above constitution, and has a specific storage elastic modulus.
Excellent flexibility and mechanical properties at high temperatures, especially compression set at high temperatures.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI theme coat ゛ (reference) C08G 69/44 C08G 69/44 C08L 71/02 C08L 71/02 77/12 77/12 F-term (reference) 4J001 DA04 DB05 DC02 DC03 DC05 EB74 EB75 ED63 ED66 EE57A GB16 GC05 JA01 JA04 JA05 JB21 JB23 4J002 CF10W CH01X CH02X ER006 FD010 FD050 FD060 FD070 FD100 FD160 FD200 4J029 AA03 AB05 BA05 BA02 BA05 AC02 AD10 AE17 EG09 HA01 HB01 HB03A JC152 JE182 KD01 KD07 KE02 KE05 KH01 4J034 BA07 DA01 DA05 DB04 DB07 DF01 DF12 DF16 DF20 DF21 DF22 DG02 DG03 DG04 DG06 DH02 DH05 DH06 DH10 HA01 HC07 HC01 HC01 HC07 HC12 HC01 HC07 HC12 HC01 HC07 HC12 KC16 KC17 KC18 KC23 KD02 KD04 KD05 KD12 KE01 KE02 PA03 QB14 QB15 RA02 RA03 RA08 RA09 RA12 RA14

Claims (2)

[Claims] A crystalline aromatic polyester component is contained in the structure, and the storage elastic modulus at 23 ° C. is 1 × 10 ^{7 to} 6 ×.
10 ⁷ is Pa, and an ester-based elastomer, wherein the storage elastic modulus in definitive to 160 ° C. is ^{2 × 10 6 ~5 × 10 7} Pa. 2. A short-chain polyester component represented by the general formula (1) and a long-chain polyester component represented by the general formula (2) repeated, wherein the short-chain polyester component is 50 to 95% by weight. A polyester copolymer (A) wherein the long-chain polyester component is 50 to 5% by weight.
Polyether (B) 50 to 500 composed of a repeating unit represented by the general formula (3) with respect to 100 parts by weight.
2. The ester-based elastomer according to claim 1, further comprising 10 parts by weight of the isocyanate component and 10 to 100 parts by weight of the isocyanate component (C). —CO—R ⁰ —CO—O—R ¹ —O— (1) —CO—R ⁰ —CO—O—R ² — (2) —R ³ —O—. ·· (3) -O-CO- NH-R 4 -NH-CO-O- ·· (4) -CO-NH-R 4 -NH-CO-O- ···· (5) ( wherein , R ⁰ represents a divalent hydrocarbon group having 6 to 12 carbon atoms, R ¹ represents an alkylene group having 2 to 8 carbon atoms, and R ² represents —RO— (where R represents 2 carbon atoms. And a number average molecular weight of 500 to 5000. R ³ has 2 carbon atoms.
And R ⁴ represents an alkylene group having 2 to 15 carbon atoms, a phenylene group, or a combination of a methylene group and a phenylene group.