JPH051218A - Polyester composition - Google Patents

Abstract

PURPOSE:To obtain a polyester composition which has a high crystallization rate and excellent moldability in a low-temperature mold and can give a molding excellent in mechanical properties, etc., by mixing a specified polyester resin with a specified amide compound and a specified reinforcing or filling substance in a specified mixing ratio. CONSTITUTION:This composition is prepared by mixing a specified amount of a polyester resin prepared by adding a specified amount of a phenolic organic sulfonate of formula I [wherein Ar is a 6-30C aromatic ring; M is an alkali (alkaline earth) metal; (m) is 1-2; and (n) is 1-5] to a specified amount of a thermoplastic polyester comprising an 8-20C aromatic dicarboxylic acid (lower alkyl ester) and a 2-20C diol before completion of the polycondensation of the polyester with a specified amount of an amide compound obtained by the condensation of compounds of formulas II and III (wherein R<1> and R<3> are 1-35C aliphatic groups or aromatic groups and are not aromatic groups simultaneously; R2 is H or a 1-4C aliphatic group; and (k) and (l) are each 1-3 and are not 1 and 3 simultaneously) and having a specified molecular weight and a specified melting point, and a specified amount of a reinforcing or filling substance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester composition which has a high crystallization rate, is excellent in moldability when used in a mold at low temperature, and has good mechanical properties, electrical properties and weather resistance.

[0002]

BACKGROUND OF THE INVENTION Thermoplastic polyesters are being used in a wide range of fields because of their excellent mechanical properties, physical properties, and chemical properties. Among them, some thermoplastic polyesters such as polyethylene terephthalate are
At present, it has not been applied to injection molding applications while having particularly excellent characteristics. This is particularly used in polyethylene terephthalate because it has a slower crystallization rate than other crystalline polymers, and is therefore used in ordinary injection molding.
This is due to a problem with the moldability that a mold at a low temperature of 0 to 95 ° C. does not sufficiently crystallize and a satisfactory molded product cannot be obtained.

Therefore, for the purpose of improving the moldability, various methods have hitherto been studied in order to improve the crystallization rate of the thermoplastic polyester.

For example, in Japanese Unexamined Patent Publication No. 56-57825, it is indispensable that an aromatic metal ring selected from a benzene ring, a naphthalene ring and an anthracene ring is bound with an alkali metal salified sulfonic acid group and an alkali metal salified phenolic hydroxyl group. A crystallization accelerator for polyester is disclosed.

Further, JP-A-58-52343, JP-A-58-83049, and JP-A-58-93750.
JP-A-93754 and the like disclose polyethylene terephthalate in which the nucleating agent and / or polyamide which does not melt at a melting point of 270 ° C. or less is used as a nucleating agent and a plasticizer is used in combination therewith to improve the crystallization rate.

Further, in JP-A-58-83048, this nucleating agent and an N-substituted aromatic amide compound are used in combination,
Polyester resin compositions having improved crystallization rates are disclosed.

Further, Japanese Unexamined Patent Publication No. 56-92918 discloses a high-speed crystallized polyester characterized in that the polyester is polymerized in the presence of a copolymerization component for metallizing the end of the polyester or an alkali metal. The method of adding a monoamide compound to this polyester is also reported therein.

Further, Japanese Patent Application Laid-Open No. 55-78051 discloses a polyethylene terephthalate resin which has improved moldability by using an ordinary polyamide resin in combination with an epoxy compound having a polyoxyalkylene chain.

Although it is not a method for improving the crystallization rate,
JP-A-60-192765 discloses a method of adding a diamide compound to various thermoplastic resins including polyester to improve the moldability (flowability) of the resin.

[0010]

However, even if the above method is applied, the crystallization rate of the polyester is not improved so much, and the mechanical properties of the molded product are deteriorated.

Therefore, the object of the present invention is to significantly improve the crystallization rate of the thermoplastic polyester, improve the moldability, and obtain a polyester resin composition having good mechanical properties.

[0012]

That is, the present invention is as follows.
(A) An aromatic dicarboxylic acid having 8 to 20 carbon atoms or a lower alkyl ester thereof and a diol having 2 to 20 carbon atoms are used as starting materials, and 100 parts by weight of a thermoplastic polyester is represented by the following general formula (1). Polyester resin containing 0.01 to 20 parts by weight of a phenolic hydroxyl group-containing organic sulfonate before completion of polycondensation of the thermoplastic polyester 100 parts by weight HO-Ar- (SO _3- (M) _{1 / m} ) _n formula (1) (wherein Ar is an aromatic ring having 6 to 30 carbon atoms, M is an alkali or alkaline earth metal, m is 1 or 2, and n is
Represents an integer of 1 to 5. ), (B) reinforcing or filling substance 5 to 140 parts by weight and (C) a compound having a molecular weight of 400 to 5,000 and a melting point of 270 ° C. or less synthesized by a dehydration condensation reaction of the compounds represented by the following formulas (2) and (3). A polyester composition containing 0.1 to 10 parts by weight of an amide compound.

R ¹ (NHR ² ) _k formula (2) R ³ (COOH) _l formula (3) (wherein R ¹ and R ³ are aliphatic groups or aromatic groups having 1 to 35 carbon atoms, R ² Is hydrogen or an aliphatic group having 1 to 4 carbon atoms, provided that R ¹ and R ³ must not be aromatic groups at the same time, and k and l in the formulas (2) and (3) are both 1 Is an integer of 3 to 3, but k and l must not be 1 or 3 at the same time.) In the present invention, a metal salt of an aromatic sulfonic acid containing a phenolic hydroxyl group before completion of polymerization of the thermoplastic polyester. It is important to add a reinforcing or filler material and a specific amide compound to the polyester resin to which is added, whereby the original purpose can be effectively achieved.

The thermoplastic polyester used in the present invention is a polymer or copolymer obtained by a polycondensation reaction containing a dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative) as main components. It is a polymer.

Examples of the dicarboxylic acid used herein include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid and 2,2'-biphenyl. Dicarboxylic acid, 3,3'-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid, 4 , 4'-Diphenylisopropylidene dicarboxylic acid, 1,2-bis (phenoxy) ethane-
4,4'-dicarboxylic acid, 2,5-anthracene dicarboxylic acid, 2,6-anthracene dicarboxylic acid, 4,4 '
Aromatic dicarboxylic acids such as -p-terphenylenedicarboxylic acid and 2,5-pyridinedicarboxylic acid, adipic acid,
Aliphatic dicarboxylic acids such as azelaic acid, dodecanedioic acid and sebacic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and terephthalic acid can be preferably used. In addition, you may use these dicarboxylic acid in mixture of 2 or more types.

As the diol component, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol,
Examples thereof include aliphatic diols such as 2-methyl-1,3-propanediol, diethylene glycol and triethylene glycol, alicyclic diols such as 1,4-cyclohexanedimethanol, and mixtures thereof. If the amount is small, one or more long chain diols having a molecular weight of 400 to 6000, that is, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like may be copolymerized.

Specific examples of thermoplastic polyesters include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycyclohexane dimethylene terephthalate and polyethylene 1,2-bis (phenoxy) ethane-. In addition to 4,4′-dicarboxylate and the like, copolymerized polyesters such as polyethylene isophthalate / terephthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / decane dicarboxylate and polycyclohexane dimethylene terephthalate / isophthalate can be mentioned. .. Of these, polybutylene terephthalate, polycyclohexane dimethylene terephthalate, polyethylene naphthalate and polyethylene terephthalate, which are well balanced in mechanical properties and moldability, can be preferably used.

The thermoplastic polyester used in the present invention has an intrinsic viscosity measured in an o-chlorophenol solution at 25 ° C. of 0.25 to 3.0 dl / g, particularly 0.4 to
2.25 dl / g is preferable.

In the present invention, the compound added before the completion of polymerization of the polyester for improving the crystallization rate has a structural formula represented by the following general formula (1).

HO-Ar- (SO _3- (M) _{1 / m} ) _n formula (1) (wherein Ar is an aromatic ring having 6 to 30 carbon atoms, M is an alkali or alkaline earth metal, and m is Is 1 or 2, n
Represents an integer of 1 to 5. In the above general formula (1), examples of the aromatic ring serving as the basic skeleton include hydrocarbon aromatic rings such as benzene, naphthalene, phenanthrene, anthracene, and pyrene, and viridine, triazine, furan, quinoline, isoquinoline,
A cyclic system including a heteroaromatic ring such as 1,10-phenanthrene and a general aromatic ring such as indene, indole, benzofuran, fluorene, and dibenzofuran is also used and is not particularly limited.

Here, it is essential that one hydroxyl group is bonded to the aromatic ring, and when it does not have a hydroxyl group, there is almost no effect of improving the crystallization rate. Further, the hydroxyl group must not be metal-chlorided with a metal such as an alkali metal. This is because when the hydroxyl groups are metal chlorides, they often become foreign substances and the effect of improving the crystallization rate is insufficient due to the strong collecting power of the salt, and the thermoplastic polyester composition is obtained. This is because the mechanical properties of the molded product are deteriorated.

Further, one or more metal chlorinated sulfonic acid groups must be bonded to the aromatic ring, but it is desirable that the number of these groups is small. This is the same reason as above. That is, when the amount of this group is too large, it is not uniformly dispersed in the polymerization system and becomes a foreign substance, which lowers the effect of improving the crystallization rate and deteriorates the mechanical properties of the molded product. Therefore, the number of metal chloride sulfonate groups is preferably 2 or less, most preferably 1.

The above-mentioned hydroxyl group and metal sulfonate group can be bound to any position of the aromatic ring where they can be bound. However, the degree of the effect of improving the crystallization rate obtained depends on the position of the substituent. For example, in the case of sodium phenolsulfonate, the positions of the substituents can be three positions of ortho, meta, and para, but it is the para position that significantly improves the crystallization rate.
The meta position tends to reduce the effect of improving the crystallization rate. In the case of phenol disulphonic acid disodium salt, the bonding position of sulfonic acid is 2,3; 2,4;
2,5; 2,6; 3,4; 3,5, of which 6,6,3;
It is 5 and the 3rd and 5th positions are particularly preferable.

As described in the above examples, those in which a substituent is bonded to the aromatic ring so as not to break the symmetry are particularly preferable because the effect of improving the crystallization rate is great.

Further, the additive of the present invention may contain another substituent other than the hydroxyl group and the metal sulfonate group, as long as the effect of the present invention is not impaired. Such substituents include aliphatic groups such as methyl and ethyl,
Chlorine, bromine, and other halogen groups, cyano groups, nitro groups, acetyl, propionyl, benzoyl, and other acyl groups, methylsulfonyl, ethylsulfonyl, phenylsulfonyl, toluylsulfonyl, and other sulfonyl groups, N
-Phenylcarboxamide, N-ethylcarboxamide, N
Carboxamide groups such as propylcarbamide, alkoxy groups such as methoxy and ethoxy, and aromatic groups such as phenyl are mentioned, and among them, aliphatic groups, halogen groups and alkoxy groups are preferable.

Specific examples of the compound represented by the above formula (1) include compounds obtained by metallizing the sulfonic acid group of the following compounds with an alkali metal or an alkaline earth metal.

That is, as the base compound, o-
Phenolsulfonic acid, m-phenolsulfonic acid, p
-Phenol sulfonic acid, 1-hydroxy-3,5-benzenedisulfonic acid, 1-hydroxy-2,6-benzenedisulfonic acid, 1-hydroxy-2,4-benzenedisulfonic acid, 1-hydroxy-3,4-benzene Examples thereof include disulfonic acid, 2-naphthol-6-sulfonic acid, 1-naphthol-5-sulfonic acid and 1-naphthol-4-sulfonic acid, 9-hydroxy-10-anthracenesulfonic acid, and among them, phenolsulfonic acid, In particular, p-phenol sulfonic acid is the most preferable in terms of performance and economy.

As the metal of the metal salt of the sulfonic acid compound used in the present invention, alkali metals such as lithium, sodium, potassium, rubidium and cesium and alkaline earth metals such as calcium and barium are preferable, and lithium is particularly preferable among alkali metals. And sodium are preferred.

The addition amount of the sulfonic acid metal salt compound in the present invention is 0.01 to 20 parts by weight, preferably 0.05 to 10 parts by weight, relative to 100 parts by weight of the thermoplastic polyester.
Parts by weight, more preferably 0.1 to 5 parts by weight. If the addition amount is less than 0.01 part by weight, the effect of improving the crystallinity of the thermoplastic polyester is not sufficient, and if it exceeds 20 parts by weight, the melt viscosity increases and the fluidity of the resin deteriorates, and the mechanical properties are It is not preferable because it tends to decrease.

The sulfonic acid metal salt compound of the present invention must be added before the completion of polymerization in order to obtain an excellent effect of improving the crystallization rate. Further, the polymerization conditions have been devised so that the obtained polyester resin has a molecular weight of 2,000 or less in terms of polystyrene and a sulfur concentration of 0.
Polymerization to contain 1 to 20% by weight of a polyester component in an amount of 005% by weight or more is preferable because a polyester having particularly excellent crystallization rate and mechanical properties can be obtained. In order to further improve the effect of improving the crystallization rate, the sulfur concentration of the polyester component having a molecular weight of 2000 or less should be 0.005% or more, particularly 0.01% or more, and more preferably 0.05% or more. desirable.

In the case of a polyester having a particularly excellent crystallization rate, the molecular weight distribution often has a peak or a shoulder in a region having a molecular weight of about 1000.

The reason why the presence of this low molecular weight greatly improves the crystallization rate of the polyester must be studied further. However, when this low molecular weight component was separated by gel permeation chromatography and subjected to elemental analysis, it was found that the sulfur content was high, and this low molecular weight component was found to have an alkali metal salt with a phenolic hydroxyl group added. It is considered that the crystallization rate is greatly improved by taking the structure of being added to the polyester oligomer and finely dispersing it in the polyester. When an ordinary polyester oligomer that does not contain sulfur is added to the polyester, or when the polymerization is carried out under the conditions that such an oligomer is formed during the polymerization, the effect of improving the crystallization rate is hardly recognized and the sulfur is contained. The resulting oligomer has a particularly large effect of improving the crystallization rate.

The content of oligomers having a molecular weight of 2000 or less can be measured by a usual gel permeation chromatography method. As the solvent, o-chlorophenol / chloroform = 1/4 (vol / vol), and as the detector, a differential refractometer can be used. That is, the column is calibrated using polystyrene with a narrow molecular weight distribution, and the ratio of the area after the retention time corresponding to the molecular weight of polystyrene 2000 to the total area narrowed by the output curve and baseline of polyester is calculated. Calculate the oligomer content.

The amount of sulfur contained in the oligomer is obtained by taking out a polyester component having a molecular weight of 2000 or less,
It can be determined by quantification by elemental analysis.

The amount of this oligomer varies depending on the addition timing of the sulfonate compound having a phenolic hydroxyl group and the addition method (powder, solution, suspension), and also the reaction of esterification reaction, transesterification reaction or polymerization reaction. It is also greatly affected by the conditions (type of catalyst, amount of catalyst, temperature, speed of temperature increase, degree of pressure reduction, speed of pressure reduction, etc.). By the sulfonate compound having a phenolic hydroxyl group to be added,
The optimum conditions are different, and it cannot be stated in a general way, but in general, the addition time of a sulfonate compound having a phenolic hydroxyl group is when the ester exchange reaction, the initial stage of the esterification reaction, or even before the reaction. Often give desirable results.

Examples of the (B) reinforcing or filling substance used in the composition of the present invention include glass fiber, carbon fiber, metal fiber, aramid fiber, asbestos, potassium titanate whiskers, wollastonite, glass flakes, glass beads and talc. , Mica, clay, calcium carbonate, barium sulfate, titanium oxide, aluminum oxide and the like. Among them, chopped strand type glass fiber is preferably used. The addition amount of these is 5 to 140 parts by weight, particularly preferably 5 to 100 parts by weight, based on 100 parts by weight of the thermoplastic polyester.

(C) used in the present invention is an amide compound synthesized by a dehydration condensation reaction of the compounds represented by the following formulas (2) and (3).

R ¹ (NHR ² ) _k Formula (2) R ³ (COOH) _l Formula (3) Here, the amine compound used in the synthesis of this amide compound R ^{1 in} Formula (2) has ¹ to 35 carbon atoms. It is an aliphatic group or an aromatic group, and R ² is hydrogen or a carbon number of 1 to 1.
4 is an aliphatic group and k is an integer of 1-3. Further, R ¹ may contain a substituent which does not inhibit the amidation reaction between the formulas (2) and (3) or a substituent which does not inhibit the effects of the present invention. Examples of the substituent include an aliphatic group such as methyl and ethyl, an acyl group such as acetyl and benzoyl, an alkoxy group such as methoxy and ethoxy, and an aromatic group such as phenyl.

Specific examples of the compound represented by the above formula (2) include methylamine, n-butylamine, n-octylamine, stearylamine, s-butylamine, 3-amino-2,2-dimethylbutane, 1, Monoamines such as 2-dimethylpropylamine, benzylamine, 1,2-diphenylethylamine, 3-amino-1-phenylbutane, aniline and naphthylamine, or ethylenediamine, hexamethylenediamine, 1,7-diaminoheptane, 1,12- Diaminododecane, 1,2-diamino-2-methylpropane, 2,2-dimethyl-1,
3-propanediamine, m-xylylenediamine, p-
Di- and triamines such as xylylenediamine, dianidine, o-tolidine, benzidine and 1,2,4-triaminobenzene, among which stearylamine, ethylenediamine, hexamethylenediamine, m-
Xylylenediamine and p-xylylenediamine are preferably used. Carboxylic Acids R ^{3 in} Formula (3) is an aliphatic group having 1 to 35 carbon atoms or an aromatic group, and l is an integer of 1 to 3. R ³ may contain a substituent which does not inhibit the amidation reaction with the formula (2) or a substituent which does not inhibit the effects of the present invention. Examples of the substituent include an aliphatic group such as methyl and ethyl, an acyl group such as acetyl and benzoyl, an alkoxy group such as methoxy and ethoxy, and an aromatic group such as phenyl.

Specific examples of the compound represented by the above formula (3) include acetic acid, lauric acid, palmitic acid, stearic acid, montanic acid, 3-methylvaleric acid, benzoic acid, 1-naphthalenecarboxylic acid and 2-naphthalene. Monocarboxylic acids such as carboxylic acid and anthracene-2-carboxylic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, octadecane-1,18-dicarboxylic acid, terephthalic acid, orthophthalic acid, 2,6-naphthalene Examples thereof include dicarboxylic acids, 2,2′-biphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4′-dicarboxylic acid, and di- and tricarboxylic acids such as trimellitic acid. Among them, lauric acid, Stearic acid, adipic acid, sebacic acid, terephthalic acid, orthophthalic acid can be preferably used.

Here, R ¹ and R ^{2 of the} amide compound component (C) synthesized from these amine and carboxylic acid must not be aromatic groups at the same time. This is because the flexible aliphatic chain has an extremely high effect in improving the crystallization rate of the polyester, and when R ¹ and R ³ in the amide are both rigid aromatic groups, the crystallization rate is high. This is because it is hardly improved. That is, it is essential that at least one of R ¹ and R ³ is an aliphatic group.

The molecular weight of the amide compound (C) is 400-5.
It is 000. When the molecular weight is less than 400, it volatilizes during the production of the composition, and a sufficient improvement of the crystallization rate cannot be obtained. When it exceeds 5,000, the compatibility with the polyester is lowered and the effect of improving the crystallization rate is reduced. It is not preferable because it becomes smaller. Therefore, the molecular weight is 400 or more and 5000 or less, preferably 500 or more and 3000 or less.

The amine component of the amide compound (C)
It is also not preferable that k and l in formula (2) and carboxylic acid component in formula (3) are 1 at the same time. When k and l are 1 at the same time, the ratio of amide groups in the compound is small, so that the volatility is higher than that of di- or tri-amide compounds having the same molecular weight, and the compatibility with polyester is low, resulting in crystallinity. This is not preferable because the effect of improving the rate of conversion becomes small. When k and l are both 3, a highly crosslinked polyamide is obtained, but a highly crosslinked polymer shows almost no effect of improving the crystallization rate, and therefore it is not preferable when k and l are 3 at the same time. .. That is, k and l in the equations (2) and (3) are l when k (or l) is 1.
Most preferably, (or k) is 2, or 3, or both k and l are 2. The amide compound (C) can be used even if a small amount of unreacted carboxyl group and amino group remains in the amide compound (C). It tends to cause a decrease in the molecular weight of the polyester and deteriorate the physical properties. Also,
Hydrolysis resistance tends to decrease and coloring tends to occur easily. Therefore, it is preferable to completely carry out the amidation reaction and reduce the contents of free carboxyl groups and amino groups. Further, when neither k nor l is 1, it is difficult to completely react the carboxyl group and the amino group, and especially when the amide compound (C) has a small molecular weight, the number of free functional groups increases. Tend. In this case, it is preferable to eliminate a free functional group by using a monofunctional compound having k or 1 of 1 in combination during the amidation reaction, or by further reacting after synthesis of the amide compound.

The melting point of the amide compound (C) is 270 ° C. or lower. When the melting point is higher than 270 ° C., the crystallization rate is not improved because the composition does not exhibit a sufficient plasticizing effect during processing. Further, in the case of polyethylene terephthalate, which is a commonly used polyester, since the amide component (C) has already solidified at the temperature at which the polyester crystallizes, there is no plasticizing effect and no effect of improving the crystallization rate is exhibited. .. Generally, the addition of a compound having a higher melting point than the polymer facilitates the formation of crystal nuclei,
It is well known to improve the crystallization rate. In the above-mentioned JP-A-58-52343, etc., it is stated that the addition of such a high melting point amide compound improves the crystallization rate. However, the polyester resin obtained by adding the phenolic hydroxyl group-containing sulfonate (A) of the present invention already has a high ability to generate crystal nuclei, and even if a high melting point amide compound is added thereto, the crystal nuclei are increased. The productivity is not improved, and the effect of improving the crystallization rate is hardly recognized. On the other hand, the amide compound having a melting point of 270 ° C. or less according to the present invention is a plasticizer that enhances the mobility of molecules, not the ability to generate crystal nuclei, and is used in combination with the polyester resin (A) having high nucleation ability. In this case, it is considered that the remarkable effect of improving the crystallization rate is exhibited.

When an N-substituted aromatic amide as disclosed in JP-A-58-83048 is used in combination with the polyester resin (A) of the present invention, the effect of improving the crystallization rate is not shown. This is because of the mechanism of action described above,
Since the main skeleton of the N-substituted aromatic amide molecule is composed of an aromatic group, it is considered that there is no effect of increasing the mobility of the polyester molecule and no effect of improving the crystallization rate.

The addition amount of the amide compound (C) is 0.1 to 10 parts by weight based on 100 parts by weight of polyester.
If it is less than 0.1 part by weight, the effect of improving the crystallization rate is not sufficient, and if it exceeds 10 parts by weight, mechanical properties, heat resistance and electrical properties are deteriorated, which is not preferable.

The following compounds may be mentioned as preferred representative examples of the amide compound (C).

[0048]

[Chemical 1]

[0049]

[Chemical 2]

It is generally known that an amide compound such as ethylenebisstearylamide is added to a polyester resin to improve releasability and fluidity. JP-A-60-19
A similar example is reported in Japanese Patent No. 2765. Certainly, when these compounds are added to the polyester resin, there is an effect of improving releasability and fluidity, but the effect of improving the crystallization rate is insufficient, and the mold temperature is 50 to 95 ° C.
It is necessary to add the crystal nucleating agent shown in (A) in order to obtain a highly heat-resistant material that has a good surface and is fully crystallized with a thin product with a thickness of 1/16 inch with the low temperature mold of Met.

That is, in order to improve the crystallization rate of the polyester resin, it is necessary to use (A) and (C) together.
By this method, the crystallization rate is dramatically improved, and even when a thin-walled product is molded with a low-temperature mold, it is sufficiently crystallized, and a material having a good surface and excellent mechanical properties, heat resistance, and electrical properties can be obtained. all right.

The use of various organic acid salts and inorganic compounds known as moldability improving agents for thermoplastic polyesters represented by polyethylene terephthalate in combination with the polyester composition of the present invention also improves molding processability. Is preferred. Specific examples of these compounds include sodium stearate, stearates such as barium stearate, sodium salts of partially saponified montanic acid esters, barium salts, ionomers, sodium salts of β-diketones, talc and salicylanilide. Examples thereof include sodium salts, sodium salts of salicylaldehyde and sodium salts of substituted phenols such as sodium salts of nitrophenol.

Further, with respect to the polyester composition of the present invention, an antioxidant, a heat stabilizer, an ultraviolet absorber, a lubricant, a release agent and a coloring agent containing a dye / pigment, etc. within a range not impairing the object of the present invention. One or more of the usual additives can be added.

A small amount of a thermoplastic resin such as polycarbonate, polyamide, polyphenylene oxide,
Polypropylene, polyethylene, ethylene / propylene copolymer, ethylene / butene-1 copolymer, ethylene /
Propylene / non-conjugated diene copolymer, ethylene / ethyl acrylate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer and ethylene / propylene-g-maleic anhydride copolymer Coalescence and the like can also be added.

The method for producing the polyester composition of the present invention and the method for adding the above-mentioned additives thereto are not particularly limited, and the method for adding the polyester at the final stage of polymerization or melt kneading using an extruder is used. Examples of the method include addition of the phenolic hydroxyl group-containing organic sulfonate represented by the formula (1) to the component (A) before completion of polymerization, and other additives include an extruder. It is desirable to melt and knead by using.

The polyester composition of the present invention can be easily molded by a usual method such as injection molding or extrusion molding, and the obtained molded product exhibits excellent performance.
In particular, in injection molding, it has a feature that the moldability is good even if a mold at a low temperature of 50 to 95 ° C. is used.

Further, the molded product has particularly good mechanical properties, electric characteristics such as arc resistance, weather resistance and the like.

[0058]

EXAMPLES The effects of the present invention will be described in more detail below with reference to examples.

Reference Example 1 100 parts by weight of dimethyl terephthalate, 62 parts by weight of ethylene glycol, 0.16 part by weight of lithium acetate, 0.04 part by weight of antimony trioxide and 0.02 of manganese acetate.
To the mixture of 3 parts by weight, 3 parts by weight of sodium p-phenolsulfonate was added. Raise this to 140 ° C,
After the dimethyl terephthalate has melted, start stirring,
The temperature was raised from 140 ° C. to 245 ° C. over 3.5 hours to carry out a transesterification reaction, and most of the methanol was distilled off. Then, the temperature was raised from 245 ° C. to 280 ° C. over 3 hours, and a vacuum was gradually applied to carry out polymerization under a vacuum of 0.6 mmHg.

The intrinsic viscosity of the o-chlorophenol solution at 25 ° C. was measured and found to be 0.61 dl / g.

The polyethylene terephthalate composition thus obtained was subjected to differential thermal analysis using a differential scanning calorimeter manufactured by Perkin Elmer Co., Ltd., and the temperature rising crystallization temperature and the temperature falling crystallization temperature were measured to evaluate the crystallinity. As is generally well known, the crystallinity improves as the temperature falling crystallization temperature increases and the temperature rising crystallization temperature decreases, so that ΔT = (temperature falling crystallization temperature)-( ΔT when the temperature rise crystallization temperature) was used as an index of crystallinity. ΔT was 93 ° C.

Reference Example 2 Polymerization was carried out in the same manner as in Reference Example 1 except that p-phenolsulfonic acid sodium salt was not added. Polyethylene terephthalate having an intrinsic viscosity of 0.61 dl / g and a ΔT of 22 ° C. was obtained.

Reference Example 3 In place of p-phenolsulfonic acid sodium salt, p-
Polymerization was performed in the same manner as in Reference Example 1 except that 2 parts of phenolsulfonic acid disodium salt was added. Polyethylene terephthalate having an intrinsic viscosity of 0.62 dl / g and a ΔT of 71 ° C. was obtained.

Examples 1 to 3, Comparative Examples 1 to 5 To 100 parts by weight of the obtained polyethylene terephthalate, chopped strand type glass fiber (3 mm
40 parts by weight (length, diameter 13 μ), and the crystallization promoter shown in Table 1 were blended by dry blending, and melt-kneaded into pellets by a 35 mmφ twin-screw extruder set at 285 ° C.

Further, the pellets were dehumidified and dried at 145 ° C. for 5 hours, and then injection time / cooling time / intermediate time 15 seconds / 20 seconds / using a screw in-line injection molding machine having a mold clamping pressure of 75 t set to 275 ° C. 5 seconds, mold temperature 75 ℃
At, length 40mm, width 60mm, depth 20mm, wall thickness 1.5mm
The box-shaped molded article was molded, and the force (release force) required to separate the box-shaped molded article from the mold was determined.

Under the same injection conditions, ASTM-1
No. dumbbell was molded, and the tensile properties were measured according to ASTM D-638.

A 1/16 inch bending test piece was molded under the same injection conditions, and the deflection temperature under high load was measured by a method similar to ASTM D-648.

The above results are also shown in Table 1.

[0069]

[Table 1]

Compounds 1 to 8 in Table 1 have the following structures.

[0071]

[Chemical 3]

From the results shown in Table 1, the polyester composition of the present invention has a significantly improved crystallization rate, exhibits good mold releasability even in a low temperature mold, has good mechanical properties, and can be molded into thin-walled articles. It can be seen that it exhibits high heat resistance because of its high crystallization rate.

[0073]

Since the polyester composition of the present invention has a high crystallization rate, it has excellent moldability in a low temperature mold, and the molded product obtained has good mechanical properties, electrical properties and weather resistance. Therefore, it is particularly useful as an electric / electronic component, an automobile component, a mechanical mechanism component, or the like.

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Claims (1)

Claims: 1. A thermoplastic polyester 100 comprising (A) an aromatic dicarboxylic acid having 8 to 20 carbon atoms or a lower alkyl ester thereof and a diol having 2 to 20 carbon atoms as a starting material.
Polyester resin obtained by adding 0.01 to 20 parts by weight of a phenolic hydroxyl group-containing organic sulfonate represented by the following general formula (1) to parts by weight before completion of polycondensation of the thermoplastic polyester. parts _{HO-Ar- (SO 3 - (} M) 1 / m) n formula (1) (in the formula, Ar an aromatic ring having 6 to 30 carbon atoms, M is an alkali or alkaline earth metal, m is 1 or 2 for n
Represents an integer of 1 to 5. ), (B) reinforcing or filling substance 5 to 140 parts by weight and (C) a compound having a molecular weight of 400 to 5,000 and a melting point of 270 ° C. or less synthesized by a dehydration condensation reaction of the compounds represented by the following formulas (2) and (3). A polyester composition comprising 0.1 to 10 parts by weight of an amide compound. R ¹ (NHR ² ) _k formula (2) R ³ (COOH) _l formula (3) (wherein R ¹ and R ³ are aliphatic groups or aromatic groups having 1 to 35 carbon atoms, R ² is hydrogen or It is an aliphatic group having 1 to 4 carbon atoms, provided that R ¹ and R ³ cannot be aromatic groups at the same time, and k and l in the formulas (2) and (3) are both 1 to 3 It is an integer, but k and l must not be 1 or 3 at the same time.)