JPH0116268B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyester compositions. More particularly, the present invention relates to crystalline polyester resin compositions with high crystallization rates useful in molding applications. Thermoplastic, crystalline polyesters, especially polyethylene terephthalate, are important as raw materials for the production of fibers, films and molded articles. Due to its partially crystalline structure, it has remarkable properties such as high wear resistance, favorable creep properties and high dimensional stability, making it suitable for molded parts that are susceptible to severe mechanical stress and exposed to severe heat. Suitable for manufacturing etc. However, polyethylene terephthalate has a slow crystallization rate and requires a high mold temperature (approximately 140°C) and a relatively long pressing time to produce molded products, which is disadvantageous when producing molded products by injection molding. It is. Furthermore, even in polyethylene terephthalate, which has a high crystallization rate and has therefore become widely used as a polyester resin for molding in recent years, increasing the crystallization rate even further can shorten the molding cycle and reduce manufacturing costs. This is a big advantage. The present inventors have made extensive studies to obtain a crystallization promoter that increases the crystallization rate and causes rapid crystallization, and have found that alkali metal salts of higher fatty acids having 26 or more carbon atoms are extremely effective. ,Special request 1982
- Filed as No. 42250. However, further detailed study revealed that polyester resin was heated to 80°C.
When injected into a mold at ~60°C and rapidly cooled, the polyester resin solidified in a glass state can be crystallized even from the glass state, achieving a high crystallization rate and resulting in We realized that this is important for realizing more advanced mechanical properties. The purpose of the above is to design the polyester resin so that even in the glass state, the polyester molecular chains can operate to some extent and be oriented and crystallized. This involves replacing some of the molecular chains of the polyester resin with molecular chains that are more mobile, that is, introducing an appropriate comonomer, and adding appropriate additives that are compatible with the matrix polyester resin. There is a way to do it.
As a result of intensive study on the latter method, the present inventors discovered that a certain type of ester can serve as an additive that achieves the above object, and arrived at the present invention. That is, the gist of the present invention is a polyester composition in which 0.1 to 10 parts by weight of dibenzyl ester of polyethylene oxydiglycolic acid is blended with 100 parts by weight of polyester, and In addition to 0.1 to 10 parts by weight of dibenzyl ester of acid,
A polyester composition containing 0.1 to 10 parts by weight of a crystallization accelerator. To further explain the present invention in detail, the polyester used as one of the raw materials in the present invention is mainly polyethylene terephthalate and polybutylene terephthalate, but some of the terephthalic acid components or glycol components are It may also be substituted with a copolymer component. Copolymerization components include bifunctional dicarboxylic acids such as isophthalic acid, naphthalene dicarboxylic acid, 4,4'-diphenoxyethane dicarboxylic acid, adipic acid, and sebacic acid; diol components include;
ethylene glycol, trimethylene glycol,
Tetramethylene glycol, hexamethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol,
Examples include copolyglycols of polyethylene glycol and polypropylene glycol. Of course, two or more of these polyesters may be used in combination. Preferred polyester is polyethylene terephthalate or 80 mol%
A crystalline thermoplastic polyester having ethylene terephthalate repeating units as above, and a crystalline thermoplastic polyester having polybutylene terephthalate or a butylene terephthalate repeating unit of 80 mol % or more. The intrinsic viscosity of polyester (value measured at 30°C using a mixed solvent of phenol/tetrachloroethane (weight ratio 1/1)) is usually in the range of 0.5 to 2.0 dl/g. Next, the dibenzyl ester of polyethyleneoxydiglycolic acid used as an additive will be explained. Polyethyleneoxydiglycolic acid is a dibasic acid represented by the following general formula, and has a number average molecular weight of 200 to 10,000. HOOCCH ₂ −(OCH ₂ CH ₂ −) _o OCH ₂ COOH This can be obtained by catalytic oxidation of polyethylene glycol with oxygen or oxygen-containing gas in the presence of a platinum metal catalyst in a non-alkaline solvent. The raw material polyethylene glycol is
A polyethylene glycol selected from the group consisting of those having a number average molecular weight of about 200 to about 10,000. −(
The number of repetitions of OCH ₂ CH ₂ −) is about 4 or more
230 or less. As polyethylene oxydiglycolic acid,
PEO acid (PEO acid is a trademark) sold by Kawaken Huain Chemical Co., Ltd. can also be used. The above-mentioned polyethylene oxydiglycolic acid is converted into dibenzyl alcohol ester using an acid catalyst by the method described below. The amount of dibenzyl ester of polyethylene oxydiglycolic acid to be blended is 0.1 to 10 parts by weight, preferably 1 to 7 parts by weight, per 100 parts by weight of polyester. If the amount is less than 0.1 parts by weight, the effect of the present invention will be small, and if it is more than 10 parts by weight, mechanical properties and heat resistance will deteriorate, which is not preferable. In the present invention, the crystallization rate can be considerably increased simply by blending the dibenzyl ester of polyethylene oxydiglycolic acid with the polyester, but it is preferable to further add a crystallization promoter. Here, any known crystallization accelerator can be used as the polyester crystallization accelerator. For example, silicates such as talc, mica, clay, silica: stearic acid, montanic acid, carbon number 12
Salts of higher fatty acids having 15 to 405 carbon atoms such as carboxylic acids obtained by adding lower fatty acids such as propionic acid to α-olefins having 400 carbon atoms by the above-mentioned known method, such as sodium, potassium or calcium salts, olefins and acrylic acids. Mention may be made of sodium or potassium salts of acids or copolymers of methacrylic acid. Of course, these may be used in combination. The crystallization accelerator is blended in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the polyester. If the amount is less than 0.1 part by weight, the effect of promoting crystallization will not be sufficient, and if it is more than 10 parts by weight, the mechanical properties of the composition will deteriorate, which is not preferable. Reinforcing materials such as glass fiber, carbon fiber, asbestos, wollastonite, and whiskers can be added to the polyester composition of the present invention within a range that does not impair its practicality. In particular, it is preferable to add glass fiber in an amount of 5 to 60% by weight based on the total composition since the mechanical properties can be significantly improved. Furthermore, known flame retardants,
An ultraviolet stabilizer, an antioxidant, a mold release agent, and a coloring agent may be added. Furthermore, other thermoplastic resins such as polyethylene, polypropylene, modified polyolefin, polystyrene, polycarbonate,
Polyamide, polyurethane, etc. may be blended. The polyester composition of the present invention is generally produced by a known method. For example, polyester, dibenzyl ester of polyethylene oxyglycolic acid, preferably a crystallization accelerator, reinforcing material if necessary, antioxidant, etc. are dry-mixed in any suitable mixer, extruder, kneader, etc. , by melt mixing in a Banbury mixer. The polyester composition obtained as described above has the advantage of a high crystallization rate. EXAMPLES Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited in any way by the following Examples. In the following, the crystallization rate was measured using a differential calorimeter (hereinafter abbreviated as DSC, model IB manufactured by PerkinElmer), which is well known in the industry. The measurement method is to weigh approximately 10 mg of the sample after melt extrusion, cool it with water, cut it into pellets using a pellet cutter, raise and lower the temperature at a rate of 16°C/min, and measure the crystallization temperature (Tcc) and melting temperature ( Tm) and 5 at 300℃
After melting for a minute, the crystallization temperature (Tc ³⁰⁰ ) when the temperature was lowered was measured. The higher the crystallization rate, the higher the Tc ³⁰⁰ and the lower the Tcc. As is clear from the comparative examples below, known crystallization promoters can raise Tc ³⁰⁰ to a considerable degree;
This is somewhat insufficient for lowering Tcc. As mentioned above, the present invention uses a certain type of ester that has the effect of assisting the mobility of polymer molecular chains at low temperatures, and as is clear from the examples below,
Significantly lowers Tcc. When such an ester is combined with a known crystallization accelerator,
A composition with a sufficiently high Tc ³⁰⁰ and a large Tcc drop is obtained. Reference example [Production of dibenzyl ester of polyethylene oxydiglycolic acid with a number average molecular weight of 400] PEO acid #400 manufactured by Kawaken Huain Chemical Co., Ltd.
(Polyethyleneoxydiglycolic acid with number average molecular weight 380-420) 200g, benzyl alcohol 114.4
g, paratoluenesulfonic acid 20g, xylene 200g
ml into a four-necked flask equipped with a water drainer, and heat to 130-140°C while removing the produced water from the reaction system.
Let it react for 3 hours. The water produced at the end of the reaction is 17.3
ml. Then, after adding 1.5 g of 40% NaOH aqueous solution,
The solvent xylene and unreacted benzyl alcohol are removed by distillation, and the solution is filtered through sodium chloride neutralized with caustic soda to obtain 280 g of dibenzyl ester. This will be referred to as PEO-BZ400. PEO acid #1000 (number average molecular weight 950-1050), PEO
Acid #4000 (number average molecular weight 3000-3700), and PEO
Acid #6000 (number average molecular weight 7800-9000) was also reacted in the same manner as above to obtain each dibenzyl ester. PEO-BZ1000, PEO-BZ4000, respectively
We will call it PEO-BZ6000. Examples 1 to 9 and Comparative Examples 1 to 6 Polyethylene terephthalate “Novapet”
(Novapet manufactured by Mitsubishi Chemical Corporation is a trademark, [η]:
0.66 dl/g, hereinafter referred to as PET. ), various crystallization accelerators, and dibenzyl ester of polyethylene oxydiglycolic acid are dry-blended in a predetermined ratio, and then melt-mixed using an extruder equipped with a 20 mm diameter Dalmage single screw (L/D = 28). The obtained strands were cooled with water and then cut into pellets. The crystallization behavior of this pellet was measured using DSC in the manner described above. In Table 1, (i) Crystallization promoter A was synthesized as follows. Dialene 30 (manufactured by Mitsubishi Chemical Corporation, carbon number 30)
After charging 167.5 g of the above α-olefin mixture (having an average carbon number of 43 calculated from the iodine value (Dialen is a registered trademark) and 185 g of propionic acid), the temperature was raised to 135 to 140° C. under a nitrogen atmosphere. Next, 9.2 g of di-t-butyl peroxide was added dropwise over 4 hours, and the mixture was further heated and stirred at the same temperature for 10 hours. When unreacted propionic acid is removed by distillation under reduced pressure, α with a carbon number of 33 or more is obtained.
-Higher fatty acids whose main component is methylmonocarboxylic acid (average carbon number 46 calculated from iodine value)
178.6g was obtained. This is called α-fatty acid 30. Add 10 ml of xylene to 30,100 g of the above α-fatty acid, heat it to 140℃, and then add 30% caustic soda solution 9.
g was added dropwise over about 1 hour, and the mixture was heated and stirred while removing water from the reaction system. After approximately 7.5 ml of water had been removed, 115 g of the sodium salt of α-fatty acids was obtained by distilling the xylene under reduced pressure. This is crystallization promoter A. (ii) Crystallization accelerator B is talc and is Micron White-5000S manufactured by Hayashi Kasei (Micron White is a trademark). (iii) Crystallization accelerator C is a metal salt of a copolymer of ethylene and methacrylic acid, and is grade number 1601 (sodium salt) of Surlyn (Surlyn is a registered trademark of DuPont) manufactured by DuPont, USA. (iv) The amount added is 3% by weight for crystallization promoter A and 3% by weight for crystallization promoter B.
1.5% by weight, 5% by weight of C, and 4% by weight of dibenzyl ester of polyethyleneoxydiglycolic acid. PET is calculated by subtracting the total amount of each additive from 100 (% by weight). 【table】

Claims (1)

[Claims] 1. Dibenzyl ester of polyethylene oxydiglycolic acid based on 100 parts by weight of polyester.
A polyester composition containing 0.1 to 10 parts by weight. 2 For 100 parts by weight of polyester, dibenzyl ester of polyethylene oxydiglycolic acid
A polyester composition containing 0.1 to 10 parts by weight of a crystallization accelerator in addition to 0.1 to 10 parts by weight. 3. The crystallization promoter is at least one compound selected from the group consisting of silicates, salts of higher fatty acids having 15 to 405 carbon atoms, and sodium or potassium salts of copolymers of olefin and acrylic acid or methacrylic acid. The composition according to claim 2, which is