JP2957231B2 - Polyester elastomer composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a polyester elastomer composition.
More specifically, it relates to a polyester elastomer composition having excellent moisture resistance and heat resistance.

[Prior Art and Problems to be Solved by the Invention] Polyester-based block copolymers are widely used as thermoplastic elastomers.

The copolymer has excellent heat resistance and durability, but a higher level is desired. Further, since the ester bond lacks in moisture resistance and durability due to its hydrolyzability, improvement is desired.

As a method for improving the heat resistance (heat resistance and durability in this specification) and the water resistance (humidity resistance in this specification) of the polyester-based block copolymer, an epoxy compound is blended with the polyester ester block copolymer. A method (see JP-A-58-162654) and a method of blending an epoxy compound with a heat stabilizer (see JP-A-59-152951) have already been reported. However, although the heat resistance and water resistance are considerably improved by these methods, they are still insufficient.

On the other hand, a method of improving heat resistance and water resistance by blending a polycarbodiimide with a polyester ether elastomer (see JP-A-47-30753) has been reported, but the water resistance at high temperatures exceeding 100 ° C. has been reported. Insufficient heat resistance and durability.

Further, a method has been reported in which a tetrafluoroethylene resin is added to polybutylene terephthalate to improve friction characteristics, abrasion characteristics and water repellency (see JP-A-63-213551). However, this method is applied to elastomers. However, the properties as an elastomer are impaired, and the durability is not improved.

The present invention has been made in order to solve the problems of the polyester-based thermoplastic elastomers conventionally used as described above and to satisfy the demand for the elastomer, that is, to improve the moisture resistance and the heat resistance of the elastomer. It is a thing.

[Means for Solving the Problems] The present invention relates to a polyester block copolymer comprising a crystalline aromatic polyester segment and a (poly) lactone segment.
The present invention relates to a polyester elastomer composition comprising 100 parts (parts by weight, hereinafter the same) of 1 to 50 parts of polyvinylidene fluoride.

[Example] The polyester block copolymer in the present invention is a polyester block copolymer having a crystalline aromatic polyester segment as a hard segment and a polylactone segment as a soft segment.

The crystalline aromatic polyester segment, which is the hard segment, is obtained by reacting a dicarboxylic acid component containing terephthalic acid and / or an ester-forming derivative thereof in an amount of 80 mol% or more with a diol component that is a glycol having 2 to 10 carbon atoms. Is the segment obtained by

Examples of the dicarboxylic acid component optionally used in a range of less than 20 mol% other than the terephthalic acid and / or its ester-forming derivative include isophthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, and the like. Sebacic acid and the like, but are not limited thereto.

Specific examples of the glycol having 2 to 10 carbon atoms as the diol component include, but are not limited to, for example, ethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane dimethanol, and the like. . Among these diol components, ethylene glycol, tetramethylene glycol and cyclohexane dimethanol are preferred from the viewpoint of mechanical strength and durability, and ethylene glycol is more preferred. The diol component may be used alone or in combination of two or more, but it is preferable to use a single glycol of 80 mol% or more in order to maintain crystallinity and a high melting point.

Preferred specific examples of the crystalline aromatic polyester segment produced from the dicarboxylic acid component and the diol component as described above include a polyethylene terephthalate segment, a polytetramethylene terephthalate segment, and a poly-1,4-cyclohexylene dimethylene terephthalate segment. And polyethylene-2,6-naphthalate segment. One of these segments may be contained in one polyester block copolymer, or two or more thereof may be contained.

Examples of the (poly) lactone segment as the soft segment include ε-caprolactone, methyl-
ε-caprolactone, dimethyl-ε-caprolactone,
Specific examples include (poly) lactone segments produced using at least one of trimethyl-ε-caprolactone, β-propiolactone, pivalolactone, α-valerolactone, enantholactone, caprylolactone, and the like. It is not limited to these. Of these segments, a (poly) lactone segment from ε-caprolactone is preferred. One of these segments may be contained in one polyester block copolymer, or two or more thereof may be contained.

The polyester block copolymer used in the present invention is produced, for example, by reacting a crystalline aromatic polyester with (poly) lactone.

Preferred specific examples of the polyester ester block copolymer obtained by reacting the crystalline aromatic polyester with (poly) lactone include, for example, a polyethylene terephthalate / polycaprolactone block copolymer and a polytetramethylene terephthalate / polycaprolactone block. Copolymers and the like are exemplified, and among them, polyethylene terephthalate / polycaprolactone block copolymer is particularly preferred, but is not limited thereto.

Examples of a method for obtaining the polyester ester block copolymer include a method in which a crystalline aromatic polyester is reacted with a (poly) lactone in a batch system, a method in which a continuous reaction is performed, and the like.

The polyester block copolymer used in the present invention may be used alone or in combination of two or more.

The polyvinylidene fluoride used in the present invention is a component used for improving the moisture resistance and heat resistance of the polyester block copolymer used in the present invention.
The properties required for such polyvinylidene fluoride include a melting point at which it can be melted and kneaded with the elastomer at 270 ° C.
That is, polyvinylidene fluoride is particularly preferable from the viewpoint of dispersibility.

The amount of polyvinylidene fluoride used in the present invention is usually 1 to 50 parts per 100 parts of the polyester block copolymer.
Parts, preferably 2 to 40 parts. If the amount is less than 1 part, the effect of improving heat resistance, moisture resistance and oil resistance cannot be sufficiently obtained. If the amount exceeds 50 parts, moldability is poor, phase separation occurs and flow marks are observed on the surface of the molded article. Become like

The composition of the present invention may optionally contain a nucleating agent. There is no particular limitation on the crystal nucleating agent used, and generally known ones can be used, but an organic compound containing a metal carboxylate in the molecule or a polymer compound containing a metal carboxylate in the molecule can be used. Preferably, from the viewpoint of compatibility and dispersibility with respect to the polyester block copolymer,
A metal carboxylate having a number average molecular weight of 1,000 or less is particularly preferred.

Further, the composition of the present invention may contain an epoxy compound which is generally used as a stabilizer. There is no particular limitation on the structure of such an epoxy compound, and the epoxy compound may be a monofunctional epoxy compound or a polyfunctional epoxy compound, but preferably has an epoxy equivalent of about 70 to 1000 g / equivalent. . These epoxy compounds may be used alone or in combination of two or more. Epoxy here is a concept including glycidyl.

Further, the composition of the present invention, other than the above-mentioned additives, other well-known heat stabilizers, catalyst deactivators, lubricants, fillers, weathering agents, pigments, thermoplastic polymers, etc. You may mix.

There is no particular limitation on the method for preparing the polyester elastomer composition obtained by blending the fluororesin with the polyester block copolymer of the present invention, and any method can be adopted as long as each component can be uniformly melt-mixed. For example, it may be prepared by a usual method such as a method of dry-blending a polyester block copolymer pellet, the above-mentioned fluororesin and, if necessary, an additive, followed by heating and melting with an extruder and mixing.

The polyester elastomer composition of the present invention thus obtained is one in which the moisture resistance and durability of the polyester block copolymer have been well improved, and the heat resistance and durability have been further improved, and as a material for molding materials, films, fibers and the like. It can be suitably used.

Next, the polyester 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. The properties of the polyester block copolymer (polyester elastomer) in each Example were evaluated by the following methods.

(Logarithmic viscosity) Phenol / tetrachloroethane as solvent (weight ratio)
Using a 50/50 mixture, the concentration is measured using an Ubbelohde viscometer at a concentration of 0.5 g / dl and a temperature of 25 ° C.

(Tensile rupture elongation) Measured according to JIS K 6301 using a No. 3 dumbbell having a thickness of 3 mm and molded by a 1-oz injection molding machine.

(Moisture resistance) After holding No. 3 dumbbell with a thickness of 3mm for 32 hours in a 170 ° C oven that supplies water at an average of 30cc / hr as water vapor, measure the tensile elongation at break and hold it against the initial value. Calculate the rate.

(Heat resistance / durability) After holding a No. 3 dumbbell having a thickness of 3 mm in a hot air drier kept at 195 ° C for 10 days, the tensile elongation at break is measured, and the retention ratio to the initial value is calculated.

Examples 1-3 Polyethylene terephthalate / polycaprolactone block copolymer (70/30 by weight) (logarithmic viscosity 1.05) 100
Parts of vinylidene fluoride resin (KF polymer # 1000 manufactured by Kureha Chemical Industry Co., Ltd.) in the amounts shown in Table 1 (2, 5, and 40 parts, respectively), 0.3 parts of sodium montanate, and diethylene glycol diglycidyl ether After 1.0 part and 0.3 part of Irganox 1010 (manufactured by Ciba Geigy) were dry-blended, the mixture was extruded at 250 ° C. using a 32 mm co-rotating twin screw extruder (L / D = 25.5), pelletized after water cooling. The characteristics were evaluated using the obtained pelletized composition. The results are shown in Table 1.

Comparative Examples 1-2 The compositions were prepared and evaluated in the same manner as in Examples 1-3, except that the amount of the vinylidene fluoride resin used in Examples 1-3 was changed as shown in Table 1. . The results are shown in Table 1.

The results in Table 1 show that the composition of the present invention is excellent as a polyester elastomer composition in both moisture resistance and heat resistance.

[Effects of the Invention] The composition of the present invention is a polyester elastomer composition in which the moisture resistance and durability are improved and the heat resistance and durability are further improved, and the demand for the conventional polyester-based block copolymer is satisfied. is there.

Continuation of the front page (56) References JP-A-59-213755 (JP, A) JP-A-59-210968 (JP, A) JP-A-60-76561 (JP, A) JP-A-59-152951 (JP) , A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 67/00-67/08 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. Polyvinylidene fluoride is added to 100 parts by weight of a polyester block copolymer comprising a crystalline aromatic polyester segment and a (poly) lactone segment.
A polyester elastomer composition containing up to 50 parts by weight. 2. The composition according to claim 1, wherein the polyester block copolymer is a polyester ester block copolymer comprising a polyethylene terephthalate segment or a polybutylene terephthalate segment and a (poly) caprolactone segment.