JP3153312B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a highly crystalline polyester resin composition. More specifically, the present invention relates to a thermoplastic resin composition capable of obtaining a molded article having a high degree of crystallization without lowering productivity by injection molding or the like in which the crystallization rate of a polyalkylene terephthalate resin having a low crystallization rate is improved.

[0002]

2. Description of the Related Art Polyalkylene terephthalate resins are used in many industrial products such as fibers and films because of their excellent mechanical properties and chemical resistance. Among them, polyethylene terephthalate is expanding its use to food containers and the like by utilizing its excellent gas barrier properties. More recently, the high crystalline melting point has been used to make applications such as food containers that can be used in microwave ovens and electronic components for heating appliances that require more heat resistance. There is a growing demand to use it as a sexual material.

[0003]

Polyethylene terephthalate has a low glass transition temperature of about 70 ° C., and its heat resistance in an amorphous state or a state of low crystallinity is governed by its glass transition temperature, and sufficient heat resistance is obtained. I can't get it. Furthermore, since the crystallization rate at low temperatures is low, the molded product obtained at a mold temperature of about 120 ° C. or lower used in ordinary injection molding has a difference in crystallinity between the outer surface and the inner part, and has heat resistance, Mechanical properties and dimensional stability are poor, and it is extremely difficult to obtain a satisfactory molded product.

On the other hand, since the crystalline melting point of polyethylene terephthalate is as high as 250 ° C. or higher, the higher the crystallinity, the more the heat resistance becomes the melting point, and the heat resistance is remarkably improved.
Therefore, in order to obtain a molded product with sufficient crystallinity,
A method of using a high-temperature mold utilizing the property of increasing the crystallization rate at high temperatures, a method of adding talc, sodium benzoate, etc. as a crystal nucleating agent and further adding polyethylene glycol, etc. as a crystallization accelerator have been proposed. .

[0005] However, the method using a high-temperature mold requires a special device for raising the temperature of the mold, and further increases the molding cycle and lowers productivity. In addition, when talc is used as a method using a crystal nucleating agent, the crystallization promoting effect is not sufficient, and when sodium benzoate is used, the crystallization promoting effect is excellent, but polyethylene terephthalate is decomposed to improve the mechanical properties. This leads to a decrease in melt viscosity and the like. For this reason, it is difficult to form a strand at the time of preparing a compound using an extruder, and the productivity is significantly reduced.

[0006]

Means for Solving the Problems In order to realize high heat resistance of a polyalkylene terephthalate-based resin molded product obtained by injection molding, the present inventors conducted research on improving the crystallinity of the polyalkylene terephthalate-based resin. As a result of the superposition, it has been found that by adding a metal salt of a polyalkylene oxide derivative to a polyalkylene terephthalate-based resin, the crystallinity is remarkably improved and the decrease in viscosity upon melting is suppressed, and the present invention has been achieved.

That is, the first invention of the present invention (Claim 1)
Is (A) a polyalkylene terephthalate-based thermoplastic resin and (B) a general formula MOOC-R1- (OR2) _n -OR3-COOM (where M is a metal atom, R1 and R3 are alkylene groups and And / or a phenylene group, R2 represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 to 100.) A metal salt of a polyalkylene oxide derivative represented by the following formula: It is a resin composition.

The second invention (Claim 2) is the thermoplastic resin composition according to claim 1, further comprising a thermoplastic resin other than the polyalkylene terephthalate-based thermoplastic resin.

The third invention (Claim 3) further comprises a nucleating agent and / or a crystallization accelerator and / or a filler. A composition.

The polyalkylene terephthalate resin used as an essential component in the present invention is not particularly limited as long as it has at least 50 mol% or more of alkylene terephthalate repeating units. Examples of the alkylene terephthalate repeating unit include a polyethylene terephthalate component and a polybutylene terephthalate component. Further, the polyalkylene terephthalate-based resin may be a polyethylene terephthalate or polybutylene terephthalate homopolymer, a copolymer with another copolymerizable component, or a block resin with another resin. Good.

Examples of the copolymer include a copolymer of polyethylene terephthalate or polybutylene terephthalate, dicarboxylic acid or its ester-forming derivative, and diol or its ester-forming derivative.

Examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, and naphthalene-
Examples thereof include dicarboxylic acids such as 2,7-dicarboxylic acid, adipic acid, and sebacic acid, and ester-forming derivatives thereof.

Examples of the diol component include diols such as ethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, cyclohexane dimethanol, 1,4-bisoxyethoxybenzene, bisphenol A, and ester-forming derivatives thereof. Can be

Each of these dicarboxylic acid components and diol components can be used in combination of two or more.

Examples of the block resin include a block resin of polyethylene terephthalate or polybutylene terephthalate and a polyalkylene oxide. Examples of the polyalkylene oxide component include polyethylene oxide and polypropylene oxide.

These polyalkylene terephthalate resins can be used in combination of two or more.

The polyalkylene terephthalate resin used in the present invention is preferably polyethylene terephthalate.

In the present invention, as an essential component, a general formula MOOC-R1- (O-R2) _n -O-R3-COOM (where M is a metal atom, R1 and R3 are an alkylene group and / or a phenylene group, R2 represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 to 100).

In the present invention, R1 and R3 are preferably a methylene group, R2 is an ethylene group or a propylene group, and n is 1
~ 40 are used. The metal component of the metal salt is not particularly limited, but an alkali metal belonging to Group 1A of the periodic table, such as lithium, sodium, or potassium, is preferably used.

Examples of the metal salts of these polyalkylene oxide derivatives include lithium polyethylene oxide diglycolic acid salt, polyethylene oxide diglycolic acid sodium salt, polyethylene oxide diglycolic acid potassium salt, polypropylene oxide diglycolic acid lithium salt, and polypropylene oxide. Sodium diglycolic acid, potassium potassium polyethylene glycol diglycolic acid and the like can be mentioned. These metal salts of polyalkylene oxide derivatives can be used in combination of two or more.

The addition amount of the metal salt of the polyalkylene oxide derivative is determined based on the amount of the polyalkylene terephthalate resin 100
The amount is preferably from 0.001 to 10 parts by weight, more preferably from 0.01 to 5 parts by weight based on part by weight. If the amount is less than this range, the crystallization promoting effect is insufficient, and if the amount is more than this range, not only the crystallization promoting effect is saturated but also the mechanical properties of the resin may be degraded.

The resin other than the polyalkylene terephthalate resin used in the present invention is not particularly limited as long as it is a thermoplastic resin, and can be used effectively. Typical examples thereof include polystyrene resin, acrylonitrile / styrene resin, acrylonitrile / butadiene / styrene resin, methyl methacrylate / butadiene / styrene resin, polycarbonate resin, and (modified). Polyethylene [Note "(modified)" means that either a non-modified polymer or a modified polymer can be used. same as below. ], (Modified) polypropylene, (modified) ethylene-propylene copolymer resin,
Polybutene, polyvinyl acetate, ethylene / vinyl acetate copolymer resin, ethylene / vinyl alcohol copolymer resin, polyphenylene ether, thermoplastic polyurethane resin, polyamide, polyacetal, polybutadiene, polymethyl methacrylate, styrene / maleic anhydride copolymer resin, Styrene / N-phenylmaleimide / maleic anhydride copolymer resin, styrene / N-phenylmaleimide / acrylonitrile copolymer resin, styrene / N-phenylmaleimide copolymer resin, and the like. It is also possible to use them in combination.
Furthermore, a resin mixture, a graft resin, a block resin or the like containing at least two kinds selected from these resins as components can also be used.

The resin composition of the present invention may further contain a nucleating agent and / or a crystallization accelerator and / or a filler.

The nucleating agent that can be used in the present invention is not particularly limited as long as it is generally used as a nucleating agent for resins, but is generally known as a nucleating agent for polyethylene terephthalate or polybutylene terephthalate. Compounds can be used preferably. Examples thereof include talc, clay, mica, kaolin, silica, carbon black, graphite, metal oxides, sulfates, phosphates, metal salts of organic phosphorus compounds, silicates, oxalates, benzoates, and pyrophosphates. Ferrite, titanium dioxide, montan wax ester salt, sulfonate, metal glycolate, α-
Examples include olefin / α, β-unsaturated carboxylate copolymers.

Among these compounds used as a crystal nucleating agent, those having a large effect of improving the crystallinity in combination with the resin composition of the present invention have an average particle diameter of 10 μm.
The following talc is an α-olefin / α, β-unsaturated carboxylate alkali (earth) metal salt copolymer.

These nucleating agents can be used in combination of two or more kinds, and the addition amount is preferably in the range of 0 to 10 parts by weight, more preferably 100 parts by weight of the polyalkylene terephthalate resin. Is 0-5
It is in the range of parts by weight. If the amount is more than this, adverse effects such as lowering of mechanical properties of the resin composition occur.

The crystallization accelerator that can be used in the present invention is not particularly limited as long as it is generally used as a crystallization accelerator for resins, but may be used as a crystallization accelerator for polyethylene terephthalate or polybutylene terephthalate. Generally known compounds can be preferably used. Examples thereof include higher fatty acid amides such as stearic acid amide, palmitic acid amide, methylenebisstearylamide, and ethylenebisstearylamide; and aliphatic acids such as ethylene glycol, triethylene glycol, neopentyl glycol, pentaerythritol, and polyethylene glycol. Dibenzoic acid esters, diphenyl esters, dialkyl esters of polyols, benzoic acid esters, phenyl esters, alkyl esters of polyethylene glycol monoglycidyl ether, and polyethylene glycol
Call and the like.

These crystallization accelerators can be used in combination of two or more kinds, and the addition amount is preferably in the range of 0 to 20 parts by weight, more preferably 100 parts by weight of the polyalkylene terephthalate resin. Is 0
The range is 10 parts by weight. If the amount is larger than this, adverse effects such as an increase in volatile components at the time of molding and mold contamination will occur.

The filler that can be used in the present invention is not particularly limited as long as it is generally used as a resin filler. Examples thereof include glass fibers, asbestos, carbon fibers, aromatic polyamide fibers, potassium titanate fibers, metal fibers, ceramic fibers, fibrous fillers such as boron whisker fibers, mica, silica, talc, clay, and carbonic acid. Examples include powdery, granular, and plate-like inorganic fillers such as calcium, glass beads, and glass flakes.

These fillers are blended for the purpose of improving mechanical, thermal, electrical or other properties. In particular, when a fibrous filler typified by glass fiber is blended, it is simply reinforced. In addition to the conventional effects, a remarkable heat resistance improving effect is exhibited by the combined use with a metal salt of a polyalkylene oxide derivative, which is an essential component of the present invention, or other known nucleating agents, crystallization accelerators and the like.

Further, these fillers may be treated with a sizing agent, a coupling agent and other surface treatment agents.

These fillers can be used in combination of two or more kinds, and the addition amount is preferably in the range of 0 to 200 parts by weight based on 100 parts by weight of the polyalkylene terephthalate resin. If the amount is more than this, adverse effects such as lowering the moldability of the resin composition are caused.

The method of mixing the thermoplastic resin and the metal salt of the polyalkylene oxide derivative, the crystal nucleating agent, the crystallization accelerator, the filler and the like are not particularly limited, and any method can be used as long as they can be uniformly mixed. Means can also be employed. For example, mixing, kneading, and the like by various mixing machines such as an extruder, a Henschel mixer, a Banbury mixer, a kneader, and a heating roll can be appropriately adopted. At this time, if necessary, various additives in an amount to exert its effect, for example, a release agent,
Lubricants, plasticizers, UV absorbers, light stabilizers, antioxidants,
Heat stabilizers, anti-aging agents, dyeing (face) agents, impact strength improvers for improving the properties of polymer blends, compatibilizing components and the like can be added.

[0034]

The following examples are provided to further illustrate the present invention. Examples 1 to 2, Comparative Examples 1 to 5 and Reference Examples 1 to 2 After mixing the components shown in Table 1 at the mixing ratios shown in the table with a Henschel mixer, a 30 mm twin screw extruder (manufactured by Ikegai Iron Works,
Using PCM-30), pellets were produced by melt-kneading and extruding at 280 ° C.

An amorphous (amorphous) sample was prepared from the pellets prepared as described above, and the temperature was changed from room temperature to 15 ° C. by a differential calorimeter (DSC-200, manufactured by Seiko Instruments Inc.).
The temperature was raised at a rate of / min to measure the temperature rise crystallization temperature (Tch). After further holding at 280 ° C for 5 minutes, the temperature was cooled at a rate of 15 ° C / minute to measure the temperature fall crystallization temperature (Tcc). did.

Further, using the same pellets, the film sample in a molten state was immediately immersed in oil at 120 ° C., held for 5 minutes to allow isothermal crystallization, and then cooled immediately. The sample crystallized in this way was subjected to density method 1
The isothermal crystallinity at 20 ° C. was measured. The crystallinity is Tch,
Evaluation was made based on Tcc, ΔT = Tcc−Tch, and crystallinity. The crystallinity can be evaluated to be better as the value of Tch is smaller, the value of Tcc is larger, the value of ΔT is larger, and the crystallinity is larger. Further, the degree of decrease in melt viscosity due to the decomposition of the resin was evaluated based on whether or not strands could be easily formed during extrusion. Table 1 shows the results.

[0037]

[Table 1]

The compound names and symbols in Table 1 are as follows. PET: Polyethylene terephthalate resin (NEH2050 manufactured by Unitika) PS: Polystyrene resin (GP-1 manufactured by Denki Kagaku Kogyo) PEO acid Na: Sodium salt of polyethylene oxide diglycolic acid (PEO acid # manufactured by Kawaken Fine Chemical Co., Ltd.)
It was prepared by neutralizing 400 with sodium hydroxide. Talc: Micro Ace L-1 manufactured by Nippon Talc Na Sodium Benzoate: Sodium Benzoate (reagent manufactured by Wako Pure Chemical Industries, Ltd.) PEG: Polyethylene glycol (PEG manufactured by NOF Corporation)
400)

[0039]

According to the present invention, a polyalkylene terephthalate resin composition having a high crystallization rate can be obtained by adding a metal salt of a polyalkylene oxide derivative to the polyalkylene terephthalate resin. As a result, a molded product having a high degree of crystallinity can be obtained without lowering the productivity, and can be suitably used as various component materials requiring heat resistance and chemical resistance.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 67/00-67/02

Claims (2)

(57) [Claims] 1. The following (A), (B) and (C) are essential components
A thermoplastic resin composition, characterized in that: (A) Polyalkylene terephthalate-based thermoplastic resin (B) General formula MOOC-R1- (O-R2) n-O-R3-COOM (where M is a metal atom, R1 and R3 are alkylene groups and / or phenylene Group, R2 is an alkylene group having 2 to 4 carbon atoms, and n is an integer of 1 to 100.) A metal salt of a polyalkylene oxide derivative (C): a crystal nucleating agent and / or a crystallization accelerator 2. The thermoplastic resin composition according to claim 1, further comprising a thermoplastic resin other than the polyalkylene terephthalate-based thermoplastic resin.