JP3098053B2 - Thermoplastic polyester resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic polyester resin composition, and more particularly to a thermoplastic polyester resin composition having excellent moldability by adding a nucleating agent, a polyoxyethylene ether compound and a specific organic phosphite-forming compound. The present invention also relates to a thermoplastic polyester resin composition having good thermal stability and mechanical properties.

[0002]

2. Description of the Related Art Thermoplastic polyester resins such as polyethylene terephthalate and polybutylene terephthalate are widely used as various molded products because of their high strength and relatively excellent heat resistance and weather resistance. ing.

[0003] Although these thermoplastic polyester resins have relatively excellent heat resistance, they do not easily crystallize when cooled from the time of heating and melting, so they need to be retained in a mold for a long time, and the moldability is high. It is not satisfactory from the viewpoint, and the presence of non-crystallized parts in the molded product tends to impair the surface smoothness and reduce mechanical properties such as strength and heat distortion temperature. Was.

Therefore, in order to increase the crystallization rate of the thermoplastic polyester resin and improve the moldability, an alkali metal salt of a carboxylic acid, an alkali metal salt of an acrylic acid copolymer, talc, barium sulfate and other inorganic substances are used. Although nucleating agents such as have been used, the effect of using the nucleating agent alone is still unsatisfactory, and it has been proposed to use a compound having a plasticizing effect such as a polyester-based or polyether-based compound in combination. For example, Japanese Patent Publication No. 47-3027 proposes using talc and a polyether compound in combination, and Japanese Patent Application Laid-Open No. 55-157647 discloses using a low molecular weight oligoester compound in combination with a nucleating agent. Japanese Patent Application Laid-Open No. 57-145145 discloses that an alkali metal salt of a carboxylic acid or an alkali metal salt of an acrylic acid copolymer is mixed with a polyether. It is proposed to use a ether compound, Japanese Patent Kokoku 2-53462 it has been proposed to use a alkali metal salt and a polyether compound of acrylic acid copolymer.

[0005] In addition, thermoplastic polyester resins are not only heated to a high temperature during molding due to a high melting temperature, but are often used for applications exposed to high temperatures by utilizing the feature of having a high thermal deformation temperature. However, there was a disadvantage that the mechanical properties deteriorated due to thermal oxidation deterioration due to such heating.

For this reason, Japanese Patent Application Laid-Open No. 62-290751 proposes that a phenolic antioxidant and a phosphorus antioxidant are further used in combination with a nucleating agent, a crystallization accelerator and a release agent. In Japanese Patent Publication No. 2-53461, a combination of an alkali metal salt of an acrylic acid copolymer and a polyether compound is further added with a phenolic antioxidant and / or
Alternatively, it has been proposed to use an organic phosphite-based antioxidant in combination, but the effect of such a combination is still only unsatisfactory in practical use, and a combination that can further improve the moldability and physical properties can be found. It was strongly desired.

[0007]

Means for Solving the Problems As a result of intensive studies to solve these problems, the present inventors have found that a combination of a nucleating agent and a polyoxyethylene dialkyl ether has a more specific organic phosphite compound. The present inventors have found that the use of a combination of these improves the moldability of a thermoplastic polyester resin and can prevent a decrease in physical properties due to heating, and thus have achieved the present invention.

That is, the present invention relates to (a) 0.01 to 5 parts by weight of a nucleating agent, and (b) polyoxyethylene ether represented by the following general formula (I) based on 100 parts by weight of a thermoplastic polyester resin. A thermoplastic polyester resin composition comprising 0.01 to 10 parts by weight of a compound and (c) 0.01 to 5 parts by weight of at least one kind of an organic phosphite compound represented by the following general formula (II): Is what you do.

R (OCH ₂ CH ₂ ) _n OR (I) (wherein R represents an alkyl group having 1 to 4 carbon atoms;
Represents 5-200. )

[0010]

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Hereinafter, the present invention having the above gist will be described in more detail.

The thermoplastic polyester resin used in the present invention is obtained by using terephthalic acid or an ester-forming derivative thereof as an acid component, and using glycol having 2 to 10 carbon atoms or an ester-forming derivative thereof as a glycol component. Such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, and poly (cyclohexane-1,
4-dimethylene) terephthalate, polyneopenthylene terephthalate and the like, and a mutual blend thereof, for example, a polymer alloy of polyethylene terephthalate and polybutylene terephthalate may be used.

Further, the thermoplastic polyester resin used in the present invention may contain a part of terephthalic acid and / or glycol as another copolymer component, for example, isophthalic acid, phthalic acid, tetrabromophthalic acid, tetrabromoterephthalic acid, Methyl isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 3,4′-diphenyldicarboxylic acid, 4,4 ′ -Aromatic dicarboxylic acids such as diphenoxyethane dicarboxylic acid; aliphatic or alicyclic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid, decane dicarboxylic acid, cyclohexane dicarboxylic acid; diethylene glycol, triethylene glycol, polyethylene Glycol, polypropylene glyco And polytetramethylene glycol; bisphenols such as hydroquinone, resorcin, 2,2-bis (4-hydroxyphenyl) propane and bis (4-hydroxyphenyl) sulfone; and ethylene oxide added to bisphenols Ether diols, which may be replaced with oxycarboxylic acids such as hydroxybenzoic acid and hydroxyethoxybenzoic acid, and the proportion of these copolymer components is about 20 mol% or less of terephthalic acid and / or glycol components; In particular, it is preferably at most 10%.

Further, these thermoplastic polyesters have a branched component, for example, trivalent or tetravalent such as tricarballylic acid, trimesic acid, trimellitic acid and pyromellitic acid.
Polycarboxylic acid and / or polyhydric alcohol such as glycerin, trimethylolpropane, pentaerythritol, etc.
Mol% or less, more preferably 0.5 mol% or less may be copolymerized.

The above thermoplastic polyester is, for example,
It can be produced by a normal production method such as a solution polymerization reaction or a method combining this and a solid phase polymerization reaction,
Commercial products can be used.

Further, the thermoplastic polyester resin of the present invention may be blended with a small proportion of another thermoplastic resin for the purpose of improving heat shrinkage and impact strength, and the like. As polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / 4-
Methyl pentene copolymer, ethylene / butene-1 copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer and maleic anhydride modified products thereof, polycarbonate, poly (polyethylene glycol / ethylene) Glycol or butylene glycol / (tere or iso) phthalate).

The nucleating agent used in the present invention includes inorganic compounds such as talc, magnesium oxide, zinc oxide, barium sulfate, sodium silicate, silicic anhydride, colloidal silica, calcium silicate, magnesium silicate, etc .; stearic acid, benzoic acid Metal salts of organic carboxylic acids such as sodium, potassium, lithium or barium salts of terephthalic acid, isophthalic acid, salicylic acid, 4-hydroxybenzoic acid, chlorobenzoic acid; copolymers of ethylene and acrylic acid or methacrylic acid, styrene Metal salts of copolymers of α-olefins such as sodium, potassium and lithium salts of maleic anhydride copolymers with α, β-unsaturated carboxylic acids; distearyl acid phosphate, bis (4-tert-butylphenyl) ) Acid phosphate, 2,2'-
Metal salts of acidic organic phosphoric acid esters such as sodium, potassium, lithium, calcium or barium salts of methylene bis (4,6-di-tert-butylphenyl) acid phosphate. In particular, talc, a metal salt of a copolymer of an α-olefin and an α, β-unsaturated carboxylic acid, a metal salt of an organic carboxylic acid, and a metal salt of an acidic organic phosphoric acid ester are preferable.

The nucleating agent is added in an amount of 0.01 to 5 parts by weight based on 100 parts by weight of the thermoplastic polyester resin.
Particularly, 0.05 to 3 parts by weight is preferable.

The following general formula (I) R (OCH ₂ CH ₂ ) _n OR (I) used in the present invention (wherein R represents an alkyl group having 1 to 4 carbon atoms;
Represents 5-200. Examples of the polyoxyethylene ether compound represented by) include polyoxyethylene dimethyl ether, polyoxyethylene diethyl ether, polyoxyethylene dipropyl ether, and polyoxyethylene dibutyl ether.
And n is preferably from 10 to 100 (molecular weight of about 500 to 4000).

The addition amount of these polyoxyethylene ether compounds is 0.1 to 20 parts by weight, particularly preferably 1 to 10 parts by weight, based on 100 parts by weight of the thermoplastic polyester resin.

Further, the following general formula (II) used in the present invention:

[0022]

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Examples of the organic phosphite compound represented by the formula include dialkyl pentaerythritol diphosphites such as ditridecyl pentaerythritol diphosphite and distearyl pentaerythritol diphosphite;
Diphenylpentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-ditertbutylphenyl) pentaerythritol diphosphite, bis (2,6-ditertbutyl-4-methyl) Diarylpentaerythritol diphosphites such as phenyl) pentaerythritol diphosphite, bis (2,4,6-tritert-butylphenyl) pentaerythritol diphosphite,
Diarylpentaerythritol diphosphite such as bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite has a large effect and is preferred.

The amount of the organic phosphite compound to be added is 0.01 to 5 parts by weight, particularly preferably 0.03 to 3 parts by weight, based on 100 parts by weight of the thermoplastic polyester resin.

The thermoplastic polyester resin composition of the present invention may contain other additives usually used, for example, inorganic fillers, phenolic antioxidants, thioether antioxidants, other nucleating agents, and other additives. A flame retardant, a release agent, a lubricant, an ultraviolet absorber, an epoxy compound, a coloring agent, an antistatic agent, a foaming agent, and the like can be added.

The inorganic filler is compounded as a reinforcing agent for the thermoplastic polyester resin or as an electric, thermal and other property modifier. The present invention relates to the case where such an inorganic filler is compounded. It is also effective.

As the inorganic filler used in the thermoplastic polyester resin, for example, glass fiber, asbestos,
Fibrous materials such as carbon fiber, potassium titanate fiber, steel fiber, ceramic fiber, boron whisker fiber, asbestos, mica, silica, calcium carbonate, glass beads,
Glass flakes, clay, powdered wollastonite,
Granular or plate-like inorganic fillers can be used.

Of these inorganic fillers, the use of glass fibers is particularly preferred because the mechanical strength and heat resistance are greatly improved and the molding shrinkage is significantly reduced.

The glass fiber is not particularly limited as long as it is generally used for reinforcing a resin. For example, a long fiber type (glass roving), short fiber chopped strand, milled fiber or the like may be used. it can. The glass fibers may be treated with a sizing agent (eg, polyvinyl acetate, polyester sizing agent, etc.), a coupling agent (eg, a silane compound, a borane compound, etc.), and other surface treatment agents. Furthermore, a thermoplastic resin,
It may be covered with a thermosetting resin or the like. The long fiber type glass fiber is usually used after being cut to a desired length before or after blending with a resin.

The amount of these inorganic fillers is usually 10 to 10 parts by weight per 100 parts by weight of the thermoplastic polyester resin.
0 parts by weight.

Examples of the phenolic antioxidant additionally used in the composition of the present invention include, for example, stearyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, thiodiethylene glycol bis [ 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,6-hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1, 3,5-tris [3-
(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 3,9 -Bis [1,1-dimethyl-2- {3- (3-tert-butyl-
4-hydroxy-5-methylphenyl) propionyloxydiethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, triethylene glycol bis [3- (3-tert-butyl-4-hydroxy) -5-methylphenyl) propionate], 2,6-di-tert-butyl-
4-methylphenol, 4,4'-butylidenebis (2
-Tert-butyl-5-methylphenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 1,1,3-tris (3-tert-butyl-4-hydroxy-6-methyl) Phenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-ditert-butyl-4-hydroxybenzyl) benzene, tris (3,5
-Di-tert-butyl-4-hydroxybenzyl) isocyanurate, tris (2,6-dimethyl-4-tert-butyl-
3-hydroxybenzyl) isocyanurate and the like.

Examples of the thioether antioxidants include dialkylthiodipropionates such as dilauryl thiodipropionate, dimyristyl and distearyl and β-polyols such as pentaerythritol tetra (β-dodecylmercaptopropionate). Alkyl mercaptopropionates can be mentioned.

[0033]

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited by the following examples.

Example 1 Polyethylene terephthalate 10 having an intrinsic viscosity of 0.72
0.5 parts by weight of talc and bis (2,6-
0.3 parts by weight of (di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and 5 parts by weight of the sample compounds shown in Table 1 were blended and uniformly mixed in a V-type blender for 5 minutes. After drying this mixture at 110 ° C. for 12 hours, it was extruded at a rotor temperature of 265 ° C. and a head temperature of 245 ° C. to obtain a ribbon-shaped compound.

This composition was placed in a DSC apparatus at 10 ° C. /
The temperature was raised to 270 ° C. at a rate of temperature rise for 5 minutes, kept at 270 ° C. for 5 minutes, cooled at a rate of temperature drop of 10 ° C./minute, and the crystallization temperature at the time of temperature decrease was measured. The higher the crystallization temperature at the time of cooling, the better the crystallinity and the better the formability. This composition was injection-molded at 260 ° C. to form a plate-like molded product, and the surface smoothness was visually observed. The results are shown in Table 1 below.

[0036]

[Table 1]

Example 2 Polyethylene terephthalate 100 having an intrinsic viscosity of 1.34
43 parts by weight of chopped strand glass fiber having a fiber length of 3 mm, 4 parts by weight of polyethylene glycol dimethyl ether (average molecular weight: 1000), and tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) based on parts by weight] 0.1 parts by weight of methane,
0.2 parts by weight of bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and a nucleating agent (Table 2) were blended and uniformly mixed in a V-type blender for 5 minutes. The mixture was dried at 140 ° C. for 5 hours and extruded at 280 ° C. to obtain a pellet-shaped compound.

The composition was injection-molded under the conditions of a cylinder temperature of 280 ° C. and a mold temperature of 110 ° C. to prepare an ASTM-1 dumbbell, and the Izod impact value and tensile strength were measured. The dumbbell specimen was placed in a 160 ° C. oven, and the Izod impact value and tensile strength after 500 hours were measured. The results are shown in Table 2 below.

[0039]

[Table 2]

Example 3 Polyethylene terephthalate 100 having an intrinsic viscosity of 1.34
With respect to parts by weight, 43 parts by weight of chopped strand glass fiber having a fiber length of 3 mm, 4 parts by weight of polyethylene glycol dimethyl ether (average molecular weight 1000), 0.5 parts of talc
Parts by weight and 0.3 parts by weight of the organic phosphite compound (Table 3) were blended and uniformly mixed in a V-type blender for 5 minutes. After drying the mixture at 140 ° C. for 5 hours, 280
Extruded at ℃ to obtain a pellet-shaped compound.

This composition was injection-molded under the conditions of a cylinder temperature of 280 ° C. and a mold temperature of 110 ° C. to prepare an ASTM-1 dumbbell, and the Izod impact value and tensile strength were measured. The dumbbell specimen was placed in a 160 ° C. oven, and the Izod impact value and tensile strength after 500 hours were measured. The results are shown in Table 3 below.

[0042]

[Table 3]

Example 4 Polybutylene terephthalate 10 having an intrinsic viscosity of 0.75
0 parts by weight, 30 parts by weight of 6 mm long chopped strand glass fiber, 30 parts of glass flakes (48 mesh)
Parts by weight, decabromodiphenyl ether 15 parts by weight, antimony trioxide 10 parts by weight, polycarbonate resin 12
Parts by weight, 0.1 part by weight of tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, bis (2,6-di-tert-butyl-4-)
(Methylphenyl) pentaerythritol diphosphite (0.1 part by weight), talc (1.0 part by weight) and the sample compound shown in Table 1 (8 parts by weight) were added, and the mixture was uniformly mixed with a blender. The mixture was extruded to form pellets, and the pellets were injection-molded at a cylinder temperature of 250 ° C. to prepare ASTM-1 dumbbells.

The tensile strength of a dumbbell specimen obtained by injection molding after allowing the resin to stay in the cylinder of the molding machine set at 260 ° C. for 30 minutes was measured and compared with the tensile strength of the unretained specimen. The result was obtained as a tensile strength retention. Table 4 shows the results.

[0045]

[Table 4]

[0046]

As is clear from the results of the above embodiments,
It is clear that the thermoplastic polyester composition of the present invention has good crystallinity and excellent moldability. In addition, the thermoplastic polyester composition of the present invention has excellent thermal stability, and a molded article produced from the composition of the present invention has a very small decrease in physical properties after being heated for a long time, and is used under severe conditions. Obviously, it is suitable for obtaining a molded article to be obtained.

────────────────────────────────────────────────── (5) Continuation of the front page (51) Int.Cl. ⁷ identification code FI C08L 23:02 71:02) (56) References JP-A-63-12656 (JP, A) JP-A-59-24747 (JP) , A) JP-A-57-145145 (JP, A) JP-B-47-3027 (JP, B1) Yoshinaga Abe, Makoto Sudo, “New Group / Plastics Compounding Agents-Basics and Applications” Taiseisha (Showa 59 (Jan 30, 30) p. 276 (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 67/00-67/04

Claims (4)

(57) [Claims] 1. A nucleating agent (a) 0.01 to 5 parts by weight, (b) a polyoxyethylene ether compound 0.01 represented by the following general formula (I), based on 100 parts by weight of a thermoplastic polyester resin. And (c) at least one kind of an organic phosphite compound represented by the following general formula (II):
A thermoplastic polyester resin composition containing 1 to 5 parts by weight. R (OCH ₂ CH ₂ ) _n OR (I) (wherein, R represents an alkyl group having 1 to 4 carbon atoms;
Represents 5-200. ) 2. The nucleating agent is talc, a metal salt of a copolymer of an α-olefin and an α, β-unsaturated carboxylic acid, a metal salt of an organic carboxylic acid, or a metal salt of an acidic organic phosphoric acid ester. The thermoplastic polyester resin composition according to claim 1. 3. The thermoplastic polyester resin composition according to claim 1, wherein the organic phosphite compound is diarylpentaerythritol diphosphite. 4. The thermoplastic polyester resin composition according to claim 3, wherein the diarylpentaerythritol diphosphite is bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite.