JPS642140B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester composition that has good moldability and provides molded articles with excellent surface gloss and mechanical properties. More specifically, the crystallization rate is high, and during injection molding, approximately 120
The present invention relates to a polyester composition that provides excellent molded products even at mold temperatures below .degree. Polyethylene terephthalate has excellent mechanical properties, electrical properties, heat resistance, chemical resistance, etc., and is useful for fibers,
It is used as a film in many industrial products. When used as fibers or films, they are usually stretched, but if they are to be used as injection molded products in plastics, for example, the stretching process described above is required. It is known that various problems occur in terms of molding and physical properties due to this.
In other words, since the crystallization rate is low at low temperatures, the molded product obtained is A difference in crystallinity occurs between the surface and the inside, resulting in nonuniform mechanical properties, dimensional stability, and shape stability.
It is extremely difficult to obtain a molded product that can withstand practical use. Conventionally, many methods have been proposed to solve these problems, such as a method of using a high-temperature mold and a method of adding a crystal nucleating agent or a crystallization promoter. However, the method using a high-temperature mold is not practical because the operation for raising the temperature is complicated, the molding cycle becomes longer, and the working efficiency is significantly lowered. On the other hand, although many methods of adding crystal nucleating agents and crystallization promoters have been studied, the crystallization speed during injection molding is still not sufficient, and the molding cycle is slower than that of other plastics. In some cases, adding crystal nucleating agents or crystallization promoters may significantly reduce the surface properties such as surface gloss, mechanical properties, thermal properties, etc. of the molded product, or may cause crystallization. Various problems occur, such as additives such as accelerators volatilizing during molding and emitting odor. The reality is that there are still many points to be considered regarding the method of adding crystal nucleating agents and crystallization promoters. Therefore, the present inventors conducted intensive research to obtain a polyethylene terephthalate composition useful as a molding material that has excellent moldability, that is, a fast crystallization rate during molding, and has excellent surface gloss and mechanical properties. As the polyethylene terephthalate resin, a specific polyethylene terephthalate resin having a specific amount of an alkali metal salt of sulfonic acid in the molecule is selected, and this resin contains (a) an inorganic compound with an average particle size of 50μ or less, and a metal with a carboxyl group. At least one of an organic compound having a salt, a polymer compound having a metal salt of a carboxyl group, and (b) a specific amount of a specific modified polyolefin or modified olefin elastomer are blended, and if necessary, a specific amount of It has been discovered that the above object can be achieved by incorporating a fibrous reinforcing material, and the present invention has been achieved. That is, the present invention is directed to polyethylene terephthalate resins (hereinafter referred to as PET-SO ₃ M
100 parts by weight of at least one of (a) an inorganic compound with an average particle size of 50 μ or less, an organic compound having a metal salt of a carboxyl group, and a polymer compound having a metal salt of a carboxyl group in 0.01 to 15 parts by weight. (b) 0.01 to 10 parts by weight of at least one compound selected from the group consisting of alicyclic carboxylic acids having a cis double bond in the ring or functional derivatives thereof in the polyolefin or polyolefin elastomer;
The present invention relates to a polyester composition containing 0.5 to 30 parts by weight of a modified polyolefin or a modified olefin elastomer added by mol%, and further containing 5 to 150 parts by weight of a fibrous reinforcing material per 100 parts by weight of the polyester composition. The present invention relates to a polyester composition containing the following parts by weight. The inventors of the present invention have previously applied for patent application No. 56-163821.
In No. 1, when specific amounts of component (a) and component (b) are added to polyethylene terephthalate or a polyester having at least 80 mol% or more of ethylene terephthalate repeating units, the crystallization rate of the polyester increases and surface gloss etc. Although it was shown that the surface properties were improved and the composition was useful as a molding material, further intensive research revealed that at least 95% by mole of the polyester
or more ethylene terephthalate repeating unit, and 0.01 per 10,000g of polyester in the molecule.
When a polyethylene terephthalate resin containing ~0.5 equivalent of an alkali metal salt of sulfonic acid is used, the crystallization rate is even higher and the surface gloss is good.If necessary, if a fibrous reinforcing material is added, It has been discovered that a composition useful as a molding material with excellent mechanical properties can be obtained. Conventionally, it has been known that adding fibrous reinforcing materials such as glass fiber to polyethylene terephthalate resin improves the mechanical and thermal properties of the polyethylene terephthalate resin. Not only is it bad, but the crystallization rate of polyethylene terephthalate resin is slow,
The molding cycle is longer and the mold temperature is e.g.
At temperatures as low as 120°C or lower, crystallization does not proceed sufficiently, which not only deteriorates the dimensional stability of the molded product, but also prevents it from fully demonstrating its original performance in terms of thermal and mechanical properties. Can not. In order to solve these problems, various studies have been conducted on adding crystal nucleating agents and crystallization promoters. They must be mixed and dispersed, and even during heating during injection molding, be stably compatible and not ooze out of the molded product or volatilize and escape. However, the compatibility of conventionally used additives with polyethylene terephthalate resins is not sufficient, and problems arise in that they may partially separate and ooze out when heated, or they may evaporate and escape. On the other hand, in the polyester composition of the present invention, since a specific modified polyolefin or modified olefin elastomer is used as component (b), the compatibility with the polyester resin is higher than that of the usual polyolefin or olefin elastomer. Even when heated, it does not separate from the polyester and ooze out or volatilize. In addition, in the present invention, a polyethylene terephthalate resin containing a specific amount of an alkali metal salt of sulfonic acid is used as the polyester, and component (A) is also blended with component (B), so that the crystallization rate is high. Mold temperature during injection molding is 120℃
Hereinafter, even at a temperature of, for example, 100 to 70°C, a molded article with excellent surface gloss can be obtained with a short cooling time. Furthermore, the polyester composition of the present invention containing a specific amount of fibrous reinforcement has excellent moldability and surface properties and excellent mechanical properties, providing a well-balanced and useful molding material. . The polyethylene terephthalate resin containing an alkali metal salt of sulfonic acid in the molecule of the present invention can be prepared by simply copolymerizing a specific amount of an ester bond-forming monomer containing an alkali metal salt of sulfonic acid, or by simply copolymerizing a specific amount of an ester bond-forming monomer containing an alkali metal salt of sulfonic acid. It can be obtained by, for example, melt-mixing polyester having a salt and polyethylene terephthalate using an extruder. Examples of the ester bond-forming monomer containing an alkali metal salt of sulfonic acid include dibasic acids containing an alkali metal salt of sulfonic acid, monoesters or diesters thereof, and glycols or oxyesters containing an alkali metal salt of sulfonic acid. Carboxylic acid derivatives are mainly used as copolymerization components, and monobasic acids or their esters containing alkali metal salts of sulfonic acids, monoalcohols containing alkali metal salts of sulfonic acids, etc. are used as polymerization terminators or terminal blocking agents. It can also be used as Examples of the ester-forming monomer containing an alkali metal salt of sulfonic acid include sodium 2,5- or 3,5-dicarboxybenzenesulfonate, 2,5- or 3,5-dicarboxybenzenesulfonate,
-Sodium dicarbomethoxybenzenesulfonate, sodium 2,5- or 3,5-di(β-hydroxyethyl)benzenesulfonate, α-
Sodium sulfosuccinic acid and its dimethyl ester, β-sodium sulfoadipic acid and its dimethyl ester, sodium 2-carbo-β-hydroxyethoxy-5-hydroxyethoxybenzenesulfonate, 3-sodium sulfo-
1,8-naphthalene dicarboxylic acid, sodium 4,4'-di(carbomethoxy)biphenyl-2-sulfonate, p-sodium sulfobenzoic acid, 3
Specific examples include sodium -hydroxypropane-1-sulfonate and compounds in which the sodium salt of the above compound is replaced with a potassium salt or lithium salt. Usually, easily available sodium or potassium 3,5-dicarboxybenzenesulfonate or its dimethyl ester is used. In the present invention, the molecule contains 10,000 polyesters.
0.01 to 0.5 alkali metal salt of sulfonic acid per g
It is necessary to use a polyester containing an equivalent amount of ethylene terephthalate repeating units and having at least 95 mol% or more of ethylene terephthalate repeating units. It is presumed that this increases the If the amount of the alkali metal salt of sulfonic acid is more than 0.5 equivalent per 10,000 g of polyester, the action of the crystal nucleating agent will increase to some extent, but the bulky alkali metal salt of sulfonic acid will adversely affect molecular orientation and crystallization. This will ultimately lead to a tendency for the crystallization rate to decrease. Conversely, if the content of alkali metal salt of sulfonic acid is less than 0.01 equivalent per 10,000 g of polyester,
The effect as a crystal nucleating agent is insufficient, and the effect is only the same as that of ordinary polyethylene terephthalate. Therefore, the content of alkali metal salt of sulfonic acid in polyester is 10,000 g of polyester.
It is necessary to suppress the content to 0.01 to 0.5 equivalents, preferably 0.01 to 0.3 equivalents, and more preferably 0.01 to 0.15 equivalents. Furthermore, the polyester used in the present invention should contain at least 95 ethylene terephthalate repeating units while suppressing the amount of alkali metal salt of sulfonic acid in the molecule to 0.01 to 0.5 equivalent per 10,000 g.
It is necessary to use a polyester with mole% or more, and the amount of ethylene terephthalate repeating units is
If it is less than 95 mol%, it may be difficult to increase the crystallization rate even if the amount of the alkali metal salt of sulfonic acid in the molecule is suppressed within the above range. Generally, when polyethylene terephthalate is produced from terephthalic acid or its ester derivative and ethylene glycol by melt polymerization, several mol% of diethylene glycol units are introduced into the main chain of the polymer due to a side reaction of ethylene glycol. It is well known that crystallization of polyethylene terephthalate is inhibited, and when an ester-forming monomer containing an alkali metal salt of sulfonic acid is copolymerized, diethylene glycol is more likely to be produced. However, in the present invention, diethylene glycol It is desirable to use a polyester having at least 95 mol %, preferably 97 mol % or more of ethylene terephthalate repeating units, with low component formation. The polyester of the present invention can be produced by copolymerizing an ester-forming monomer containing an alkali metal salt of sulfonic acid with a monomer that mainly produces ethylene terephthalate repeating units, or by copolymerizing an alkali metal salt of sulfonic acid in the molecule. Examples include a method of producing a polyester having the following and mixing it with polyethylene terephthalate. Examples of the polyolefin or olefin elastomer used as a starting material in producing the modified polyolefin or modified olefin elastomer in the present invention include homopolymers of olefins such as polyethylene, polypropylene, polybutene-1, and polypentene-1. or ethylene-propylene copolymer, ethylene-butene-1 copolymer, propylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, propylene-vinyl acetate copolymer, ethylene-butadiene copolymer, ethylene -Copolymers with different types of olefins or diolefins such as isoprene copolymers, ethylene-chloroprene copolymers, propylene-butadiene copolymers, and ethylene-propylene-butadiene copolymers can be mentioned; The polymer may be a random copolymer, a block copolymer, a graft copolymer, or an alternating copolymer. And especially ethylene-propylene copolymer,
Preferred are ethylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, ethylene-propylene-butadiene copolymer, ethylene-propylene-isoprene copolymer, ethylene-propylene-chloroprene copolymer, and the like. Two or more kinds of polyolefins or olefin-based elastomers can also be used in combination. Examples of the alicyclic carboxylic acid having a cis-type double bond in the ring in the present invention include cis-4-cyclohexene-1,2-dicarboxylic acid, endo-bicyclo-[2,2,1]-5- Heptene-2,3
-dicarboxylic acid, methyl-endo-cis-bicyclo-[2,2,1]-5-heptene-2,3-dicarboxylic acid, endo-bicyclo-[2,2,1]
-1,2,3,4,7,7-hexachloro-2-
Examples of functional derivatives include heptene-5,6-dicarboxylic acid, acid anhydrides, esters, acid amides, acid halides,
Examples include metal salts. Particularly preferred is endo-bicyclo-[2,2,1]-5-heptene-2,3-dicarboxylic acid or its acid anhydride. Note that the functional derivative does not necessarily have to be converted into a functional derivative before being added to the polyolefin or olefin elastomer, and can be converted, for example, during the modification process of the polyolefin or olefin elastomer or after forming a polyester composition. The modified polyolefin or modified olefin elastomer of the present invention refers to the polyolefin or olefin elastomer containing at least one kind selected from the group consisting of alicyclic carboxylic acids having a cis-type double bond in the ring or functional derivatives thereof. It means a modified polyolefin or a modified olefin elastomer obtained by adding a compound, or a mixture thereof with an unmodified polyolefin or an unmodified olefin elastomer. The modified polyolefin or modified olefin elastomer can be produced by various methods, but it is preferable to produce radicals by combining the polyolefin or olefin elastomer with the alicyclic carboxylic acid or functional derivative having the cis-type double bond in the ring. The above polyolefin or olefin elastomer and the above carboxylic acid or its functional derivative are dissolved in water by adding an organic peroxide such as tertiary butyl peroxide, dicumyl peroxide, or benzoyl peroxide. This is carried out by dispersing and heating in the presence of the above-mentioned radical generator or water-soluble peroxide. Here, the addition ratio of the carboxylic acid or its functional derivative to be added to the polyolefin or olefin elastomer depends on the use of the obtained polyester composition, the type of polyolefin or olefin elastomer and their mixing ratio, the carboxylic acid or its function. Although it varies depending on the type of derivative, usually 0.001 to 10 mol% of the carboxylic acid or its functional derivative added to polyolefin or olefin elastomer is used, preferably 0.01 to 5.0 mol%, more preferably 0.01 to 5.0 mol%. is added in an amount of 0.05 to 2.0 mol%. The amount of the carboxylic acid or functional derivative added is
If the amount is less than 0.001 mol%, the compatibility with PET-SO ₃ M and interfacial adhesion will be poor, and therefore the effect as a crystallization promoter will not be fully demonstrated, and if it is added in excess of 10 mol%, it will be added. Process or PET-
In the step of blending with SO ₃ M, side reactions such as lowering of the molecular weight and gelation of the polyolefin or olefin-based elastomer occur, which is not preferable. Regarding the amount of modified polyolefin or modified olefin-based elastomer, that is, component (B), if the amount of component (B) is less than 0.5 parts by weight per 100 parts by weight of polyester (PET-SO ₃ M), crystals will occur. The effect of the component (b) as a chemical accelerator is insufficient, and a molded product with excellent surface properties cannot be obtained.On the other hand, if the amount exceeds 30 parts by weight, other performances such as thermal properties deteriorate. The amount of PET
-0.5 to 30 parts by weight, preferably 0.5 to 20 parts by weight, more preferably 1 to 10 parts by weight per 100 parts by weight of SO ₃ M
Parts by weight. The effect of the inorganic compound used as component (a) of the present invention as a crystal nucleating agent differs depending on its particle size, and the effect decreases when the average particle size exceeds about 50 μm. Inorganic compounds with a diameter of 50 microns or less are useful. And the average particle size used in the present invention
Specific examples of inorganic compounds with a particle size of 50μ or less include carbon black, silica, calcium carbonate, synthetic silicic acid and silicates, zinc white, hallosite clay, kaolin, basic magnesium carbonate, mica, talc, quartz powder, and silica. algae, dolomite powder,
Examples include titanium oxide, zinc oxide, antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, etc., and one or more of these inorganic compounds can be used, among which mica, kaolin, Talc, silica are useful in this invention. Further, as the organic compound having a metal salt of a carboxyl group used in the present invention, any compound having a metal salt of a carboxyl group can be used, but usually the number of carbon atoms is about 7. ~30 higher fatty acids, metal salts of aromatic acids are used, e.g. heptanoic acid, pelargonic acid,
Metal salts of higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, cerotic acid, montanic acid, melisic acid, benzoic acid, terephthalic acid, terephthalic acid monomethyl ester, isophthalic acid, isophthalic acid monomethyl ester Specific examples include metal salts of aromatic acids such as. Further, the polymer compound having a metal salt of a carboxyl group is not particularly limited as long as it has a metal salt of a carboxyl group at the end or side chain of the polymer, but for example, it is possible to The resulting carboxyl group-containing polyethylene, the carboxyl group-containing polypropylene obtained by oxidizing polypropylene, the copolymer of olefins such as ethylene, propylene, butene-1, and (meth)acrylic acid, and the copolymer of olefins and maleic anhydride. Specific examples include metal salts such as polymers, copolymers of styrene and (meth)acrylic acid, and copolymers of styrene and maleic anhydride. Usually, olefins and (meth)acrylic acid or styrene and ( Metal salts of copolymers of meth)acrylic acid are used. As the metal that forms a salt with a carboxyl group, alkaline earth metals, alkali metals, etc. are usually used, and alkali metals have excellent effects as crystal nucleating agents, with sodium and potassium being particularly useful. The amount of this component (a) varies depending on the type of component used, but the average particle size is 50 μm.
The amount of at least one of the following inorganic compounds, organic compounds having metal salts of carboxyl groups, and polymeric compounds having metal salts of carboxyl groups is less than 0.01 parts by weight per 100 parts by weight of PET-SO ₃ M. The effect as a crystal nucleating agent is insufficient, and conversely, even if more than 15 parts by weight is added, the effect as a crystal nucleating agent is not proportional to the amount added, and the excess added is only used as a filler. It only shows the effect of Therefore, the amount of component (a) is PHT-
The amount is 0.01 to 15 parts by weight, preferably 0.05 to 10 parts by weight, and more preferably 0.1 to 5 parts by weight based on _SO3M . Specific examples of the fibrous reinforcing material used in the present invention include glass fiber, carbon fiber, aromatic polyamide fiber, silicon carbide fiber, titanate fiber, etc., but glass fiber is usually often used. be done. In addition, there are no particular restrictions on the diameter and length of each type of fiber, but if the fiber length is too long, it may become uniform with PET-SO ₃ M and other compounding agents, that is, components (a) and (b). mixture·
It is difficult to disperse, and conversely, if the fiber length is too short, the effect as a reinforcing material will be insufficient, so fiber lengths of 0.1 to 10 mm are usually used, especially when the fibrous reinforcing material is glass fiber. In some cases, the fiber length is preferably 0.1 to 7 mm, more preferably 0.3 to 4 mm.
mm is preferable. In addition, the fibrous reinforcement material is PET-
In order to improve the interfacial adhesion with SO ₃ M and increase the reinforcing effect, it is possible to use materials treated with various compounds as necessary, but when using glass fiber as a fibrous reinforcement material, can be used with various surface treatment agents, such as vinyltriethoxysilane, γ-
Methacryloxypropylmethoxysilane, β-
Silanes such as (3,4-epoxycyclohexyl)-ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-chloropropylmethoxysilane, γ-mercaptopropyltrimethoxysilane, etc. Those treated with a chromium-based treatment agent such as methacrylate chromic chloride are used. Regarding the blending amount of the fibrous reinforcing material, if the blending amount is less than 5 parts by weight per 100 parts by weight of the polyester composition consisting of PET-SO ₃ M and components (a) and (b), mechanical The effect of improving properties and thermal properties is insufficient, and on the other hand, if the amount exceeds 150 parts by weight, it becomes difficult to uniformly mix the fibrous reinforcing material into the composition. Therefore, the amount of the fibrous reinforcing material to be blended is 5 to 150 parts by weight, preferably 20 to 100 parts by weight, based on 100 parts by weight of the polyester composition before addition of the fibrous reinforcing material. The composition of the present invention may further contain various inorganic or organic compounds such as antioxidants, ultraviolet absorbers, colorants, mold release agents, fillers, etc., if necessary. The polyester composition of the present invention can be produced by mixing in various methods, and the production method is not particularly limited, but usually each component or additive is melt-mixed using an extruder or kneader. Manufactured by The composition of the present invention can be formed into various forms, such as various molded articles, films, sheets, fibrous materials, and tubular materials. Next, the present invention will be specifically explained with reference to Examples and Comparative Examples. Note that "parts" shown in Examples and Comparative Examples indicate "parts by weight." Examples 1 to 8, Comparative Examples 1 and 2 Endo-bicyclo-[2,2,1]-5 to various polyolefins or olefin elastomers
-Heptene-2,3-dicarboxylic anhydride [hereinafter abbreviated as modifier (A)] or endo-bicyclo-
[2,2,1]-5-heptene-2,3-dicarboxylic acid methyl ester [hereinafter referred to as modifier (B)] is added in various proportions, and ditertiary butyl peroxide is added to the polyolefin. Add 1 part by weight to 1000 parts by weight of olefinic elastomer, mix at room temperature with a Henschel mixer, feed the mixture to an extruder, and mix at about 200°C.
Pellets of the modified polyolefin or modified olefin elastomer shown in Table 1 were prepared by extrusion.

[Table] In addition, terephthalic acid, ethylene glycol,
Melt polymerize from 5-sodium sulfoisophthalic acid in a conventional manner to determine the sodium salt content of sulfonic acid.
A polyethylene terephthalate polymer (hereinafter abbreviated as PET-SO ₃ Na) containing 2.5 mol%, diethylene glycol content of 3.0 mol%, and ethylene terephthalate repeating units of 94.5 mol% was synthesized. The sodium salt content of sulfonic acid in this polymer is 1.28 equivalents per 10,000 g of polyester. This PET
- SO ₃ Na and polyethylene terephthalate (hereinafter abbreviated as PET) with a diethylene glycol content of 2.0 mol%, PET - SO ₃ Na/PET = 5/95,
They were mixed at a ratio of 3/97 (weight ratio) and melt-extruded to produce pellets. The sodium salt content of sulfonic acid in these pellets is 0.065 equivalent and 0.039 equivalent per 10,000 g of polyester, respectively. Next, 100 polyethylene terephthalate polymers with different contents of alkali metal salts of sulfonic acid were prepared.
In the section, talc (manufactured by Nippon Talc Co., Ltd., Micro Ace K)
-1) 1 part and 3 parts of modified polyolefin or modified olefin elastomer were mixed using a tumbler and melt extruded using a 65 mmφ extruder to produce pellets. The various samples produced in this way were measured using a differential calorimeter (manufactured by PerkinElmer).
DSC-1 type), the temperature was raised from room temperature at a rate of 20℃/min to determine the melting point (Tm), and the exothermic peak was obtained when the temperature was maintained at 280℃ for 5 minutes and then cooled at a rate of 20℃/min. The cooling crystallization temperature (Tcc) was measured.
The crystallization rate was evaluated from the Tcc value, peak shape, and ΔT=Tm−Tcc. Note that the larger the Tcc value, the sharper the Tcc peak, and the
It can be evaluated that the smaller T is, the higher the crystallization rate is. The results are shown in Table 2.

[Table] Examples 9-13 10000g of polyester produced in Examples 1-8
To 100 parts of polyethylene terephthalate pellets containing 0.039 equivalents of sodium salt of sulfonic acid in the molecule, glass fiber [manufactured by Asahi Fiberglass Co., Ltd., product number 429, 3 mm long chopped strand] was added.
After mixing predetermined amounts of the modified polyolefin (1) and various crystal nucleating agents in a tumbler, the mixture was melt-extruded using a 65 mmφ extruder to produce pellets. After drying the pellets obtained, the cylinder temperature was 240
-270-280℃, mold temperature 96℃, injection holding time 10
A test piece of 1/2 inch x 1/2 inch x 2.5 inch was molded under conditions of injection pressure of 300 to 600 Kg/ ^cm2 . At that time, the cooling time was changed and the minimum cooling time was determined from the mold releasability. All molded articles had excellent surface appearance. The results are shown in Table 3.

【table】

Claims (1)

[Claims] 1. 100 parts by weight of a polyethylene terephthalate resin having at least 95 mol% or more of ethylene terephthalate repeating units and containing 0.01 to 0.5 equivalents of an alkali metal salt of sulfonic acid per 10,000 g of polyester in the molecule. (a) 0.01 to 15 parts by weight of at least one of an inorganic compound with an average particle size of 50 μ or less, an organic compound having a metal salt of carboxylic acid, and a polymer compound having a metal salt of carboxylic acid, (b)
0.001 to 10 mol% of at least one compound selected from the group consisting of alicyclic carboxylic acids having a cis-type double bond in the ring or functional derivatives thereof in a polyolefin or polyolefin-based elastomer.
A polyester composition containing 0.5 to 30 parts by weight of an added modified polyolefin or modified olefin elastomer. 2. The polyethylene terephthalate resin containing an alkali metal salt of sulfonic acid is obtained by copolymerizing polyethylene terephthalate in a specific amount with an ester bond-forming monomer containing an alkali metal salt of sulfonic acid. The polyester composition according to item 1. 3. The polyester composition according to claim 2, wherein the ester bond-forming monomer containing an alkali metal salt is sodium 2,5- or 3,5-dicarboxybenzenesulfonate. 4. The polyester composition according to claim 1, characterized in that the inorganic compound having an average particle size of 50 μm or less is one or more inorganic substances selected from the group of talc, mica, kaolin, and silica. 5 Claim 1 in which the metal salt of carboxylic acid is a sodium salt or potassium salt of carboxylic acid
The polyester composition described in . 6 An organic compound having a metal salt of carboxylic acid is
The polyester composition of claim 1, which is a compound having about 7 to 30 carbon atoms. 7. The polyester composition according to claim 1, wherein the polymer compound having a metal salt of carboxylic acid is a copolymer of olefin and (meth)acrylic acid or a copolymer of styrene and (meth)acrylic acid. . 8 Polyolefin or polyolefin elastomer is polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene-
1. The polyester composition according to claim 1, which is an ethylene-vinyl acetate copolymer. 9 Alicyclic carboxylic acid having a cis-type double bond in the ring or its functional derivative is endo-bicyclo-[2,2,1]-5-heptene-2,3-dicarboxylic acid or its anhydride or its functional derivative. The polyester composition according to claim 1, which is a dimethyl ester. 10 To 100 parts by weight of a polyethylene terephthalate resin having at least 95 mol% or more of ethylene terephthalate repeating units and containing 0.01 to 0.5 equivalents of an alkali metal salt of sulfonic acid per 10,000 g of polyester in the molecule, (a) average particle 0.01 to 15 parts by weight of at least one of an inorganic compound having a diameter of 50 μm or less, an organic compound having a metal salt of carboxylic acid, and a polymer compound having a metal salt of carboxylic acid;
(b) A modified polyolefin or a polyolefin-based elastomer with 0.001 to 10 mol% of at least one compound selected from the group consisting of alicyclic carboxylic acids having a cis-type double bond in the ring or functional derivatives thereof; or 5 to 30 parts by weight of fibrous reinforcing material to a polyester composition containing 0.5 to 30 parts by weight of a modified olefin elastomer.
A polyester composition containing 150 parts by weight. 11. The polyester composition according to claim 10, wherein the fibrous reinforcing material is glass fiber.