JPS594644A - Modified polyester composition - Google Patents

Abstract

PURPOSE:A composition crystallizing extremely quickly even at low mold temperature, providing a molded article having improved heat resistance and appearance in small thickness in good processing characteristics, obtained by blending a specific polyoxyalkylene compound with a salt of specified organic carboxylic acid and a reinforcing filler. CONSTITUTION:(A) 100pts.wt. modified polyethylene terephthalate obtained by copolymerizing a polyethylene terephthalate-based polymer with a polyoxyalkylene compound is blended with (B) 1-200pts.wt.reinforcing filler and (C) 0.01- 10pts.wt. substance selected from a metal salt of Ia group or IIa group of periodic table of organic carboxylic acid. The polyoxyalkylene compound of the component A having preferably 400-5,000 molecular weight and containing at least one metal salt of organic acid in one molecule is used. An alkali metal salt of organic aromatic carboxylic acid is preferable as the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to modified polyethylene terephthalate compositions, particularly modified polyethylene terephthalate compositions for molding. More specifically, it is a polyethylene terephthalate composition containing a specific polyoxyalkylene compound, a specific organic carboxylate, and a specific amount of reinforcing filler.
Even when molded at a mold temperature of 100°C or less, the crystallization rate is extremely fast, the molding processability is significantly improved, the heat resistance is excellent, especially in thin walls, and the surface appearance of the molded product is uniform and glossy. The object of the present invention is to provide a new polyester composition for molding, from which certain molded articles can be obtained.

Polyethylene terephthalate resin has a high softening point and has excellent electrical properties including heat resistance, chemical resistance, and light resistance, so it is widely used in fibers, films, and molded products. Among them, when used as molded products, those containing glass fiber have a heat distortion temperature of 200°C or higher, and have extremely high heat resistance compared to other engineering plastics. However, the crystallization rate is slower than that of the same crystalline polymers such as nylon and polyacetal, and conventional thermoplastic resin molding is difficult.
At mold temperatures below 00°C, crystallization hardly progresses,
The heat deformation temperature also decreases to around OO'C, and the surface of the molded article becomes transparent, while the inside becomes opaque and non-uniform as crystallization progresses. Therefore,
Usually, it is necessary to hold the mold for a long time in a high-temperature mold of 130 to 150°C, but high-temperature molds are not common and work efficiency is still extremely low, molding costs are high, and it is not practical. become scarce.

In recent years, inorganic solid substances such as talc, metal salts of inorganic and organic acids, metal glycolates, etc. have been known to promote crystallization of polyethylene terephthalate resin, but reinforcing agents such as glass fiber and the like have been used. Even with blended products, when molded at a mold temperature of 100'C or less, crystallization has not progressed sufficiently, the surface appearance is uneven, there is no gloss at all, and the heat resistance is low. be. In particular, when a thin-walled molded product is molded, the heat resistance is significantly lowered, and only a non-uniform exterior with a semi-transparent or slightly whitened interior can be obtained.

The present inventors have discovered that even if the mold temperature during molding of polyethylene terephthalate is kept at 100°C or less, the crystallization speed is rapid and the molding processability is excellent, the surface appearance is uniform, the surface appearance is uniform, and the gloss is excellent. As a result of intensive research to obtain a molded product with high heat resistance, especially in thin parts,
This has led to the present invention. That is, the present invention provides (4) (a) a polyethylene terephthalate polymer,
(b) 100 parts by weight of modified polyethylene terephthalate obtained by copolymerizing a polyoxyalkylene compound, ω) 1 to 200 parts by weight of reinforcing filler (0 Group 1 a or The gist of the present invention is a modified polyester composition containing 0.01 to 10 parts by weight of at least one selected from Group A metal salts.

The polyethylene terephthalate polymer (a) referred to in the present invention refers to a dicarboxylic acid component in which at least 90 mol% is terephthalic acid and at least 90 mol% t.
Some are obtained by direct esterification or polycondensation after transesterification with a diol component, which is large ethylene glycol.

01 to 10 parts by weight of the dicarboxylic acid component of the polyethylene terephthalate polymer is other aromatic dicarboxylic acid having 6 to 14 carbon atoms, aliphatic dicarboxylic acid having 4 to 8 carbon atoms, or alicyclic dicarboxylic acid having 8 to 12 carbon atoms It may be. Examples of such dicarboxylic acids include phthalic acid, inphthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, adipic acid, sebacic acid, cyclohexanedicarboxylic acid, and the like.

Moreover, even if the O to 10 molar ratio of the diol component is another aliphatic diol having 3 to 10 carbon atoms, another alicyclic diol having 6 to 15 carbon atoms, or an aromatic diol having 6 to 12 carbon atoms. good. Examples of such diols are propane-1,
3-diol, butane-1,4-diol, pentane-
1,5-diol, hexane-1,6-diol, cyclohexane-1,4-dimetatool, 2,2-dimethylpropane-1,3-diol, 2,2-bis-(ehydroginecyclohexyl)-propane, 2.2-His (
Examples include 4'-hydroxyphenyl)propane and hydroquinone. Furthermore, an oxycarboxylic acid such as ε-oxycaproic acid, hydroxy-7benzoic acid, etc. may be copolymerized in an amount of 10 molar or less of the dicarboxylic acid component and the diol component. Of course, polyethylene terephthalate may also be branched with trivalent or tetravalent alcohols or tribasic or tetrabasic acids. Suitable branching agents include trimesic acid, trimellitic acid, trimethylolpropane,
Examples include pentaerythritol.

The polyoxyalkylene compound (rot) referred to in the present invention is
It is selected from the following (a) and (b).

(a) A divalent group derived from an alkylene oxide whose main component repeating unit is 02 to c4, which has at least one ester-forming group at its terminal, and The alkylene compound may be a homopolymer or a copolymer. Examples of such compounds include polyethylene glycol, polypropylene glycol, polyneopentyl glycol to polyethylene glycol, monomethoxypolyethylene glycol, polyethylene glycol/polypropylene glycol copolymer, polyethylene glycol/polytetramethylene glycol copolymer, and the like. Particularly preferred are polyethylene glycol and monomethoxypolyethylene glycol.

(b) A polyoxyalkylene compound having at least one organic acid metal salt in one molecule, and having the general formula.

R1[(OR2)β-0R3:]□ (wherein, 1 is hydrogen or an m-valent organic group, R2 is 02-C
4, l is 0 or a positive integer, R3 is a group containing hydrogen or an organic acid metal salt, and m is a positive integer of 1 to 6).

Such a polyoxyalkynone compound can be obtained by, for example, esterifying a substantially monofunctional or polyfunctional alcohol of polyoxyalkylene with a polyhydric carboxylic acid anhydride in the presence of a basic catalyst or an acid catalyst as necessary. It can also be obtained by converting a metal salt into a metal salt, or, for example, a monofunctional or polyfunctional alcohol of substantially polyoxyalkylene and a /S halogenide containing a metal salt of sulfonic acid or phosphoric acid may be used as a catalyst if necessary. It can be obtained by reacting in the presence of. Here, "substantially" means that a portion of the molecule may contain other elements or organic groups. Specific examples of such polyoxyalkylene compounds include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, mono- and dicono-phosphate potassium salts, mono- and cyphthalic acid ester sodium salts, and calcium salts of ethylene oxide-propylene oxide copolymers. salts, zinc salts, aluminum salts, mono- and di(tetrabromo)phthalic acid ester sodium salts, monotrimellitic acid ester sodium salts of monomethoxypolyethylene glycol, glycerin-alkylene oxide adducts, trinoF-o-propane-alkylene Oxide adducts mono-, jatori-, or tetraphthalic acid ester sodium salts and mono-, jatori- or tetra(tetrabromo)phthalic acid ester sodium salts, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide-propylene oxide copolymer , polyhydric alcohol-alkylene oxide adducts, etc.

Examples include sulfonic acid or phosphate sodium salts and calcium salts of Jatri or tetraphenyl ether. These polyoxyalkylene compounds may be used alone or in combination of two or more.

These polyoxyalkylene compounds are copolymerized with polyethylene terephthalate and disperse uniformly through scales, increasing the mobility of polyester segments and improving crystallization properties at low temperatures, and especially contain organic acid metal salts in the molecule. In this case, the crystallization rate is significantly improved in combination with the nucleating agent effect.

The molecular weight range of the polyoxyalkylene compound is 200~
20,000, particularly preferably 400 to 5,000 from the viewpoint of compatibility with polyester chains.

The amount of polyoxyalkylene compound used is usually 0.1 to 30% by weight, preferably 1 to 25% by weight based on polyethylene terephthalate, in view of the level of crystallization promoting effect.
It is.

In a polyoxyalkylene compound containing an organic acid metal salt, the metal content varies depending on the type and molecular weight of the polyoxyalkylene, but is usually 0.001 to 20% by weight, preferably 1 to 5% by weight. Among the organic acid metal salts, alkali metal salts of aromatic carboxylic acids are particularly preferred from the viewpoint of compatibility with polyester, crystallization promoting effect, and the like.

The reinforcing filler (B) referred to in the present invention refers to a fibrous, plate-like, or granular inorganic filler, and by blending these, mechanical strength, heat resistance, and dimensional stability can be further improved. Specific examples include glass fiber, mineral fiber, carbon fiber, silicon carbide fiber, boron carbide fiber, potassium titanate fiber, gypsum fiber, mica, talc, kaolin, clay, asbestos, calcium silicate, carunium sulfate, calcium carbonate, etc. In particular, glass fiber, mica,
Talc and mineral fibers are preferred. These may be used alone or in combination of two or more, and may be surface-treated with a silane coupling agent or the like to improve affinity with the resin. The blending amount is modified polyethylene terephthalate) 1
00 parts by weight, preferably 5 to 1 when considering mechanical strength, heat resistance, and fluidity.
It is 50 parts by weight.

The organic carboxylic acid metal salt (0) of group 1 a or group
Indicates metal salts of cycloaliphatic, aromatic, and heterocyclic carboxylic acids. Specific examples of organic carboxylic acid metal salts include sodium acetate, potassium acetate, calcium acetate, sodium propionate, lithium propionate, sodium caprate, sodium laurate, potassium laurate, sodium stearate, calcium stearate,
Barium stearate, sodium myristate J., carunium myristate, sodium palmitate, calcium palmitate, potassium palmitate, sodium benzoate, potassium benzoate, calcium benzoate,
Sodium p-t-butylbenzoate, potassium p-t-butylbenzoate, calcium p-1-butylbenzoate,
Examples include sulfur and lithium terephthalate, potassium terephthalate, lithium terephthalate, sodium phthalate, sthorium phthalate, potassium cyclohexylcarboxylate, sthorium trimellitate, and tetrapotassium pyromellitate. Furthermore, halogen-containing organic carboxylic acid metal salts such as dipotassium tetrachlorophthalate, disodium tetrabromophthalate, and disodium chloridic acid are also exemplified.

The blending amount of the metal salt of these organic carboxylic acids is 0.001 to 1.00 parts by weight per 100 parts by weight of the modified polyethylene tereclate.
0 parts by weight, preferably 01 to 3 parts by weight. 0
If it is less than 1 part by weight, the excellent heat resistance and appearance improvement effect will be small, and if it exceeds 10 parts by weight, the molded product will become brittle, which is not preferable.

The organic carboxylic acid metal salts can be used alone or in combination of two or more.

Copolymerization of the polyoxyalkylene compound in the present invention is achieved by adding and reacting during the production of polyethylene terephthalate.

As for component (g)), a method of mixing modified polyethylene terephthalate with a kneading device such as an extruder is exemplified. Examples of component (C) include a method in which it is added and mixed during the production of polyethylene terephthalate, and a method in which it is mixed with polyethylene terephthalate in a kneading device such as an extruder. Furthermore, there is also a method in which an organic carboxylic acid is added at the time of metal salt formation during the synthesis of the polyoxyalkylene compound, metal salt formation is performed at the same time, and the organic carboxylic acid is added at the same time as the polyoxyalkylene compound.

In the present invention, flame retardancy can be further improved by incorporating a flame retardant. Examples of the flame release agent to be used include compounds containing elements of group (1), group Iv, group V, and group (2) of the periodic table, with halogen compounds, phosphorus compounds, and antimony compounds being particularly preferred. These can be used alone or in combination of two or more. Specific examples of flame retardants include tetrabromobisphenol A or its derivatives, thecabromodiphenyl ether, tetrabromophthalic anhydride, perchlorocyclopentadiene derivatives,
Examples include triphenyl phosphate and antimony dioxide. The blending amount of the flame retardant is modified polyethylene terephthalate 13-
-1-0 to 30 parts by weight relative to 1.00 parts by weight.

Furthermore, in the present invention, various additives such as heat stabilizers, light stabilizers, colorants, etc. can be added as necessary.

Further, up to 50 parts by weight of other types of polymers can be blended with respect to 100 parts by weight of the composition of the present invention. Examples of such polymers include polyolefins such as polyethylene and polypropylene, ethylene-propylene copolymers, polystyrene, polymethacrylic acid esters, ABS, MBS, acrylic polymers, polyvinyl chloride, polyamides, polyacetals, polycarbonates, polysulfones, and polyphenylene oxides. Examples include, but are not limited to, nylene oxide, ethylene-vinyl acetate copolymer, aliphatic polyester, and polysiloxane.

Thus, the molded article obtained by molding the composition of the present invention is
As is clear from the examples described below, even when molded in a low-temperature mold of 100°C or less, the molded product has a uniform appearance, excellent surface gloss, and excellent heat resistance in thin walls. It can be obtained by

The present invention will be explained below with reference to Examples.

Example In a 44 autoclave equipped with a stirrer, dimethyl terephthalate (1942110 mol), ethylene glycol 1
366 g (22 mol) and 1.2 g of zinc acetate as a transesterification catalyst under nitrogen atmosphere at 160-210°C.
The transesterification reaction was carried out by heating and stirring for 2 hours. After the theoretical amount of methanol was distilled off, 4489 (0.2 mol) of disodium polyethylene glycol monotrimellitate having an average molecular weight of 2240, 21 g of triphenyl phosphate as a thermal stabilizer, 0.7 g of antimony trioxide as a polycondensation catalyst were added. was added. followed by 270°C1
The polycondensation reaction was carried out at <I Torr.

The intrinsic viscosity of the obtained polymer was 072.

To 100 parts of the obtained dried chips of modified polyethylene terephthalate, 1 part of sodium pt-butylbenzoate,
43 parts of glass fiber was blended and kneaded into pellets using an extruder and subjected to injection molding.

Cylinder temperature: 260'C1 Mold temperature: 80°C1 Molding cycle: 30 seconds to obtain a dumbbell with a thickness of 8 inches per section.
When the surface appearance was evaluated, it was found that the surface layer was sufficiently crystallized and had a uniform surface appearance with excellent gloss. A molded piece with a trench thickness of 16 inches was produced, and the weight was 18.6 kg/a.
The heat distortion temperature (HDI) of A load was measured, and an extremely high value of 230'C was obtained.

° Comparative example polyethylene terephthalate (intrinsic viscosity 0.75) 10
0 parts, 20 parts of polyethylene glycol having an average molecular weight of 1500, 12 parts of sodium pt-butylbenzoate, and 51 parts of glass fiber were blended into the resulting mixture, and the mixed pellets were made into a mixed pellet using an extruder and subjected to injection molding.

The surface appearance was partially avatar-like and lacked luster, the middle part was naturalized, and the surface layer was transparent and had an uneven appearance. 1 part 1
The HDT at 6 inches was also 120°C.

Patent applicant Kanebuchi Chemical Industry Co., Ltd. Agent: Patent Attorney Makoto Asano - 13(

Claims (3)

[Claims] (1) A, 100 parts by weight of modified polyethylene terephthalate obtained by copolymerizing (a) polyethylene terephthalate-based polymer and (b) a polyoxyalkylene compound, B, 1 to 200 parts by weight of reinforcing filler C0 organic A modified polyester composition containing 0.01 to 10 parts by weight of at least one metal salt selected from metal salts of Group 1 a or Group 2 a of the Periodic Table of carboxylic acids. (2) The molecular weight of the polyoxyalkylene compound is 400 or more
50-00. (3) The composition according to claim 1, wherein the polyoxyalkylene compound has at least one organic acid metal salt in one molecule; (4) The organic acid metal salt is an organic aromatic 4. The composition according to claim 3, which is an alkali metal salt of a group carboxylic acid.