JP2682696B2 - Polyester ester elastomer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyester ester elastomer composition. More specifically, the present invention relates to a polyester ester elastomer composition which is excellent in heat resistance and humidity resistance, and also excellent in oil resistance and moldability, and thus can be suitably used as, for example, a molding material, a film, a fiber and the like.

[Prior Art] Polyester ester block copolymers composed of crystalline aromatic polyesters and lactones have excellent rubber-like properties, heat resistance and weather resistance, but when subjected to heat treatment at high temperature for a long time, tensile rupture occurs. The elongation decreases greatly, and the moisture resistance and durability are not sufficient. Of these, polyester ester block copolymers obtained by reacting polyethylene terephthalate and lactones (hereinafter referred to as PET / PL) are compared with those obtained by reacting polybutylene terephthalate and laurones. The Vicat softening point is far superior, but it has poor oil resistance and moldability.

As a method for improving various physical properties of the polyester ester block copolymer, a method for improving heat resistance (heat resistance durability in the present invention) and (2) water resistance by adding an epoxy compound has been reported. (JP-A-58-162654). However, this method
There is no example applied to PL, and even when actually applied, heat resistance durability was not improved, oil resistance was poor, and moldability did not change.

Also, by adding an epoxy compound and a metal salt of an aliphatic carboxylic acid to the polyester ester block copolymer,
A method for simultaneously improving (1) heat resistance (heat resistance and durability in the present invention), (2) water resistance and (3) moldability has been disclosed (JP-A-59-152947). However, the effect on oil resistance is not clarified in this publication, and when this method is actually applied to PET / PL, (1) heat resistance durability, (2) moisture resistance durability, and (3) molding It was found that the oil resistance was not improved although the oil resistance was improved.

Furthermore, there is a report that the polyester ester block copolymer is blended with an epoxy compound and an isocyanate compound to improve the water resistance and the viscosity to improve the moldability (JP-A-61-162513). However, in this case as well, an example applied to PER / PL is not shown, and an effect on oil resistance is not shown. Actually, as a result of applying to PET / PL, (1) Moisture resistance and durability, (2)
It was found that neither heat resistance durability nor (3) oil resistance could be improved.

[Problems to be Solved by the Invention] Therefore, in view of the above-mentioned conventional techniques, the present inventors have made a polyester ester block copolymer (PET / PL) obtained by reacting polyethylene terephthalate with lactones.
As a result of intensive research to improve the heat resistance durability, moisture resistance durability, oil resistance and moldability in a well-balanced manner, we have found the PET / PL with excellent physical properties for the first time as a polyester ester elastomer composition and completed the present invention. Came to do.

[Means for Solving the Problems] That is, according to the present invention, 100 parts by weight of a polyester ester block copolymer obtained by reacting polyethylene terephthalate with lactones, (a) a crystal nucleating agent,
The present invention relates to a polyester ester elastomer composition containing 0.1 to 10 parts by weight of an epoxy compound and (c) 0.05 to 5 parts by weight of a bifunctional or higher functional isocyanate compound.

In the present invention, a bifunctional or higher functional isocyanate compound means a compound containing two or more isocyanates.

[Operation and Examples] The polyester ester block copolymer (hereinafter referred to as PET / PL) used in the present invention is composed of a polyethylene terephthalate segment and a polylactone segment, and has excellent rubber properties, heat resistance and weather resistance. Since it has a higher Vicat softening point than a polyester ester block copolymer composed of polybutylene terephthalate and polylactone, it is used as, for example, a molding material, a film or a fiber.

Such PET / PL is obtained, for example, by a method of reacting polyethylene terephthalate with lactones in a batch system or continuously, and in the present invention, the logarithmic viscosity is 0.7 to 2.0 dl / g, preferably 0.9 to 1.5. It is desirable to use one that is dl / g.

If the logarithmic viscosity is smaller than the above range, the resulting polyester ester elastomer composition tends to have too low heat resistance and humidity resistance, and if it exceeds the above range, the polyester ester elastomer composition is obtained. The crystallization rate tends to be slow, and moldability tends to be poor.

In addition, the polyethylene terephthalate used in the reaction to obtain PET / PL is one in which 80 mol% or more of all the constituent units are ethylene terephthalate units. Glycols such as methanol or dicarphonic acids such as isophthalic acid, adipic acid, sebacic acid may be copolymerized.

Examples of lactones include ε-caprolactone,
Methyl-ε-caprolactone, dimethyl-ε-caprolactone, trimethyl-ε-caprolactone, β-propiolactone, bivalolactone, α-valerolactone, enanthlactone, caprylolactone and the like, and among them, ε-caprolactone is Especially preferred. Such lactones may be used alone or in combination of two or more in the reaction with the polyethylene terephthalate.

The composition ratio of polyethylene terephthalate and lactones in PET / PL (weight basis, the same applies below) is 90:10.
-40: 60, preferably 80: 20-60: 40. In such a composition ratio, the proportion of polyethylene terephthalate is
If it exceeds 90, the tensile elongation at break of the obtained PET / PL tends to be small, and it tends to become difficult to become an elastomer.
If it is less than 40, the crystallization rate tends to be low and the moldability tends to be poor.

The crystal nucleating agent blended with PET / PL in the present invention is a component for crystallizing PET / PL to exhibit rubber-like elasticity. As the crystal nucleating agent, any generally known one can be used, and as such a specific example,
For example, talc having an average particle size of 50 microns or less, an inorganic compound such as kaolin, for example, stearic acid, palmitic acid, montanic acid, dimer acid, trimer acid, benzoic acid,
Organic compounds containing a carboxylic acid metal salt in the molecule such as a metal salt of naphthalene dicarboxylic acid, or, for example, ethylene-methacrylic acid copolymer, ethylene-acrylic acid copolymer, ethylene-maleic anhydride copolymer, styrene- Examples thereof include polymer compounds containing a carboxylic acid metal salt in the molecule such as a metal salt of a maleic acid copolymer. Among these, an organic compound containing a carboxylic acid metal salt in the molecule or a polymer compound containing a carboxylic acid metal salt in the molecule is preferable in that the effect of increasing the crystallization rate is large, and compatibility with PET / PL and From the viewpoint of dispersibility, a carboxylic acid metal salt having a number average molecular weight of 1,000 or less is particularly preferable.

In addition, as the metal to be neutralized to obtain the carboxylic acid metal salt, a metal of Group IA or IIA of the Periodic Table of the Elements can be used. Among them, for example, sodium, lithium, potassium, calcium, barium and the like are preferable, and sodium is particularly preferable.

These crystal nucleating agents are blended alone or in combination of two or more, and the blending amount of such crystal nucleating agent is PET / PL10.
It is desirable that the amount is 0.05 to 10 parts by weight, preferably 0.1 to 5 parts by weight, and particularly preferably 0.1 to 3 parts by weight, relative to 0 parts by weight.

If the blending amount is less than 0.05 parts by weight, crystallization is not sufficiently performed, so that the moldability tends to be poor,
On the other hand, if it exceeds 10 parts by weight, the resulting polyester ester elastomer composition tends to have poor tensile elongation at break and poor moisture resistance.

An epoxy compound is added to the PET / PL in addition to the crystal nucleating agent in order to improve heat resistance and humidity resistance. The structure of such an epoxy compound is not particularly limited, but an epoxy compound having an epoxy equivalent of 70 to 1000 g / equivalent is preferable.

Specific examples of such epoxy compounds include, for example, phenyl glycidyl ether, polyethylene glycol monophenyl monoglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, hexamethylene glycol diglycidyl ether, bisphenol A diglycidyl ether,
Examples thereof include glycerin triglycidyl ether and pentaerythritol tetraglycidyl ether.

The blending amount of such an epoxy compound cannot be unconditionally determined because it varies depending on the epoxy equivalent of the blended epoxy compound, but is usually 0.1% with respect to PET / PL100 parts by weight.
-10 parts by weight, preferably 0.2-5 parts by weight, particularly preferably 0.3-3 parts by weight. When the amount is less than 0.1 parts by weight, the effect of improving heat resistance and humidity resistance becomes too small. If it exceeds 10 parts by weight, the tensile elongation at break of the obtained composition tends to be too small.

In the present invention, PET / PL is blended with a bifunctional or higher functional isocyanate compound in order to improve oil resistance and heat resistance durability. As such an isocyanate compound,
The structure is not particularly limited as long as it is a bifunctional or higher functional isocyanate compound.

Specific examples of such an isocyanate compound include, as bifunctional compounds, hexamethylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, dicyclohexylmethane diisocyanate, and the like. Examples thereof include tri (isocyanatophenyl) methane and tri (isocyanatophenyl) thiophosphate.

The blending amount of such an isocyanate compound cannot be unconditionally determined because it depends on its molecular weight, but it is usually 0.05 to 5 parts by weight, preferably 0.1 to 2 parts by weight, particularly preferably 0.1 to 100 parts by weight of PET / PL. ~ 1 part by weight.

When the amount is less than 0.1 parts by weight, the effect of improving oil resistance and heat resistance tends to be too small, and when it exceeds 5 parts by weight, the tensile elongation at break of the obtained composition is small. Tends to be too much.

The polyester ester elastomer composition of the present invention is obtained by blending the PET / PL with the crystal nucleating agent, the epoxy compound and the difunctional or higher functional isocyanate compound as additives and mixing them.

The mixing method is not particularly limited as long as each component can be uniformly melt-mixed, but usually, for example, PET / PL chips are dry-blended with the additives including the crystal nucleating agent. After that, a method of heating and melting with an extruder and mixing, a method of mixing the above additives and melting and mixing after the completion of PET / PL polymerization and before withdrawal are used.

In the present invention, when mixing the PET / PL and the additive, it is usually well known other than the additive, for example, a heat stabilizer, a pigment, a catalyst deactivator, a lubricant, a filler, You may mix | blend a thermoplastic polymer, a weather-resistant agent, etc.

Thus obtained polyester ester elastomer composition of the present invention, PET / PL heat resistance durability, moisture resistance durability,
It has a well-balanced improvement in oil resistance and moldability, and can be suitably used as, for example, molding materials, films, fibers and the like.

Next, the polyester ester elastomer composition of the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

In addition, "parts" in Examples, Comparative Examples and Tables represent "parts by weight", and physical properties of the polyester ester elastomer compositions in each Production Example, Examples and Comparative Examples were measured according to the methods described below. It was

(Logarithmic viscosity (dl / g)) Dissolve the obtained polyester ester block copolymer or polyester ester elastomer composition in a phenol / tetrachloroethane (weight ratio 1: 1) mixed solvent to a concentration of 0.5 g / dl. Then, a polymer solution was prepared and measured at a measurement temperature of 25 ° C. using an Ubbelohde viscometer.

(Tensile rupture elongation) The obtained polyester ester elastomer chips were molded with a 1-ounce injection molding machine to form a No. 3 dumbbell-shaped test piece having a thickness of 3 mm, and this test piece was used for measurement according to JIS K 6301. .

(Heat resistance) The dumbbell-shaped test piece was subjected to 1 at 170 ° C in a gear oven.
After maintaining for 6 days, the tensile elongation at break was measured and calculated as the retention rate with respect to the initial value by the following formula.

(Heat resistance) (Humidity resistance) The dumbbell-shaped test piece was kept in a thermo-hygrostat at 80 ° C and 95% relative humidity for 12 days, and then the tensile elongation at break was measured. did.

(Moisture resistance) (Oil resistance) The dumbbell-shaped test piece was immersed in the brake oil of DOT-4 kept at 50 ° C for 7 days, and then the tensile elongation at break was measured, and the retention ratio to the initial value was calculated by the following formula (oil resistance sex) (Vicat softening point) Measured with a load of 1 kg according to JIS K 7206.

(Moldability) The releasability when the dumbbell-shaped test piece was injection-molded was evaluated according to the following criteria.

◯: 95% or more of the injection-molded test pieces were automatically released from the mold.

Δ: 70% or more of the injection-molded test pieces were automatically released from the mold.

X: Less than 70% of the injection-molded test pieces were automatically released from the mold.

Production Example 1 70 parts of polyethylene terephthalate in which 100 mol% of all structural units are ethylene terephthalate units, and ε-
A polyester ester block copolymer was obtained by dissolving 30 parts of caprolactone at 240 ° C. and polymerizing for 1 hour. When the logarithmic viscosity of the block copolymer was measured, it was confirmed to be 1.05 dl / g.

Production Example 2 A polyester ester block copolymer was obtained by dissolving 70 parts of polybutylene terephthalate, which is a butylene terephthalate unit in 100 mol% of all structural units, and 30 parts of ε-caprolactone, at 230 ° C. and then polymerizing for 1 hour. I got it.

When the logarithmic viscosity of the block copolymer was measured, it was confirmed to be 1.15 dl / g.

Example 1 To 100 parts (3 kg) of the polyester ester block copolymer obtained in Production Example 1, 0.3 part of sodium montanate, 1 part of diethylene glycol diglycididiether, and Irganox 1010 (trade name, manufactured by Ciba Geigy) as a heat stabilizer. After 0.3 parts of hexamethylene diisocyanate and 0.1 parts of triphenyl phosphate as a catalyst deactivator were dry blended, 24 parts were added using a 25 mm twin screw extruder.
It was extruded at 5 ° C. to obtain a polyester ester elastomer composition. The composition was cooled with water and pelletized into chips. When the inherent viscosity of the obtained polyester ester elastomer chip was measured, it was 1.15 dl / g.

Next, various physical properties of the obtained polyester ester elastomer chip were measured according to the methods described above. Table 1 shows the results.

Comparative Example 1 A polyester ester elastomer chip was obtained and various physical properties were measured in the same manner as in Example 1 except that the compounding amount of sodium montanate was changed as shown in Table 1. The results are shown in Table 1.

Comparative Examples 2 and 3 Instead of the polyester ester block copolymer obtained in Production Example 1, the polyester ester block copolymer obtained in Production Example 2 was used, and the amount of sodium montanate shown in Table 1 was added. Then, in the same manner as in Example 1, polyester ester elastomer chips were obtained and various physical properties were measured. The results are shown in Table 1.

From the results shown in Table 1, it can be seen that the polyester ester elastomer composition obtained in Example 1 has a higher Vicat softening point than any of the polyester ester elastomer compositions obtained in Comparative Examples 1 to 3. In addition, since the product obtained in Example 1 contains the crystal nucleating agent in an appropriate amount, the moldability, heat resistance durability, moisture resistance durability and oil resistance are well-balanced as compared with the product obtained in Comparative Example 1, It can be seen that this is a marked improvement.

Examples 2 and 3 and Comparative Example 4 Polyester ester elastomer chips were obtained and various physical properties were measured in the same manner as in Example 1 except that the compounding amount of diethylene glycol diglycidyl ether was changed as shown in Table 2. The results are also shown in Table 2.

From the results shown in Table 2, the polyester ester elastomer compositions obtained in Examples 2 and 3 in which an appropriate amount of the epoxy compound was blended were compared with those obtained in Comparative Example 4 in which the amount of the epoxy compound was too small. The heat resistance, moisture resistance and oil resistance are well-balanced and may be significantly improved.

Example 4 and Comparative Example 5 A polyester ester elastomer chip was obtained in the same manner as in Example 1 except that the compounding amount of hexamethylene diisocyanate was changed as shown in Table 3, and various physical properties were measured. The results are shown in Table 3.

From the results shown in Table 3, the polyester ester elastomer compositions obtained in Examples 1 and 4 in which an appropriate amount of the isocyanate compound was added were added to those obtained in Comparative Example 5 in which the amount of the isocyanate compound was too small. hand,
It can be seen that the oil resistance is remarkably improved.

[Effect of the Invention] The polyester ester elastomer composition of the present invention has a higher Vicat softening point than the polyester ester elastomer composition obtained by the reaction of polybutylene terephthalate and lactones, and further has heat resistance, moisture resistance, and oil resistance. Since it is excellent in balance between moldability and moldability, it can be suitably used as a molding material, a film, a fiber and the like.

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Claims (2)

(57) [Claims] 1. 100 parts by weight of a polyester ester block copolymer obtained by reacting polyethylene terephthalate with lactones, (a) a crystal nucleating agent, (b) an epoxy compound in an amount of 0.1 to 10 parts by weight, and (c). A polyester ester elastomer composition comprising 0.05 to 5 parts by weight of a bifunctional or higher isocyanate compound. 2. The polyester ester elastomer composition according to claim 1, wherein the crystal nucleating agent is an organic carboxylic acid salt.