JP3382121B2 - Polyester resin and its molded product - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various bottles, films, sheets, plates, fibers, automobile parts, exterior parts, resin molded articles such as office equipment housings, and thermoplastic polyester resins used for the molding. It is about.

[0002]

Polyester block copolymers having a crystalline aromatic polyester unit as a hard segment and an aliphatic polyether unit such as polyalkylene oxide glycol or an aliphatic polyester unit such as polylactone as a soft segment are flexible. It has excellent properties, elasticity, oil resistance, chemical resistance, mechanical properties, high temperature properties, etc., so it can be used in various applications such as various sheets, films and textiles, industrial materials, automobiles, electric and electronic parts, etc. It is used.

[0003]

However, the above-mentioned polyester resin is not sufficient in terms of heat aging resistance.
Therefore, various proposals have been made. For example, Japanese Patent Laid-Open No.
Japanese Patent No. 173059 proposes a method of adding a polyamide resin and a sulfur-based antioxidant or a phosphorus-based antioxidant. However, such a material has a problem that the polyamide resin to be added has a higher elastic modulus than the polyester resin, so that the elastic modulus of the composition after the addition is increased and other mechanical properties are changed. The present invention has been made to solve the above-mentioned problems, and has excellent molding processability, flexibility, high heat resistance, chemical resistance, mechanical properties, durability, elasticity, and a high degree of elastic recovery that a polyester resin has. The present invention is intended to provide a polyester resin having improved heat aging resistance without impairing surface gloss, chemical resistance and the like, and a molded product thereof.

[0004]

Means for Solving the Problems The inventors of the present invention have made diligent studies in view of such circumstances, and as a result, by copolymerizing a polyester resin with a specific component, thermal stability, surface appearance, and mechanical properties are improved. The inventors have found that an improved resin can be obtained, and arrived at the present invention. That is, the polyester resin of the present invention comprises (A) a dicarboxylic acid or an ester-forming derivative thereof, (B) a glycol or an ester-forming derivative thereof, and (C) a polyvalent carboxylic acid having 3 or more valences, a polyhydric alcohol or a mixture thereof. The ester-forming derivative is 0.1 to 5 mol% in the total amount of the component (A) and the component (C) in the case of a polycarboxylic acid, and the total of the component (B) and the component (C) in the case of a polyhydric alcohol. Polyester containing 0.1 to 5 mol% in the amount and (D) a compound having a unit represented by the following general formula in an amount of 3 to 65% by weight based on the total of the components (A) to (C). The resin is characterized by having an intrinsic viscosity η of 0.5 dl / g or more measured in a phenol / tetrachloroethane equivalent mixed solvent at 25 ° C.

[Chemical 2] (However, an integer of 2 ≦ m ≦ 6 and 4 ≦ n ≦ 23) The molded product of the present invention is formed by molding this polyester resin.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester resin of the present invention essentially contains at least the above-mentioned components (A) to (D). The component (A) used in the present invention is preferably one containing an aromatic dicarboxylic acid and its ester-forming derivative as a main acid component from the viewpoint of heat resistance. Aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, naphthalene-1,
4 or 2,6-dicarboxylic acid, anthracene dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4'-
Examples thereof include diphenyl ether dicarboxylic acid, 5-sulfoisophthalic acid, sodium 3-sulfoisophthalate and the like. Examples of these ester-forming derivatives include lower alkyl esters, aryl esters, carbonic acid esters, acid halides and the like. This aromatic dicarboxylic acid is preferably contained in the total acid component of the entire polyester resin in an amount of 80 mol% or more, and more preferably 85 mol% or more. This is because if the aromatic dicarboxylic acid component is less than 80 mol%, the mechanical strength of the molded product may decrease, and the productivity may also decrease. Further, an aliphatic dicarboxylic acid as an acid component other than the aromatic dicarboxylic acid,
Alternatively, these ester-forming derivatives can be contained, but in that case, it is preferable that the amount is less than 20 mol%, preferably less than 15 mol% in the total acid component.
This is because if the content is 20 mol% or more, the mechanical strength of the molded product may be reduced. Examples of the aliphatic dicarboxylic acid used in the present invention include oxalic acid, succinic acid,
Examples include glutaric acid, adipic acid, pimelic acid, sebacic acid, azelaic acid, dodecanedioic acid, dimer acid, 1,3 or 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, 4,4′-dicyclohexyldicarboxylic acid. To be

The component (B) used in the present invention is to impart color tone, transparency, heat resistance, impact resistance and the like, and various glycols described below can be applied. Ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, dimer diol, cyclohexanediol, cyclohexanedimethanol, the following general formulas (1) and (2)
Examples include alcohol components represented by and ethylene oxide adducts of these derivatives.

[Chemical 3] (In the formula, X is CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ ,
Indicates any one of O, S, and SO ₂ , and satisfies 1 ≦ n + m ≦ 4. )

[Chemical 4] (In the formula, X is CH ₂ , C (CH ₃ ) ₂ , C (CF ₃ ) ₂ ,
Any one of O, S, and SO ₂ is shown, and R is a C1 to C5 alkyl group, and 1 ≦ n + m ≦ 4 is satisfied. Among these, an ethylene oxide adduct of bisphenol A having a structure represented by the following general formula (3) is preferable.

[Chemical 5] (In the formula, 1 ≦ n + m ≦ 4 is satisfied.)

The component (C) of the present invention is a trivalent or higher polyvalent carboxylic acid, a polyhydric alcohol or an ester-forming derivative thereof. More preferably, it is trivalent to tetravalent. When the valence is less than 3, the elasticity of the obtained resin tends to be insufficient. Examples of such trivalent or higher polyvalent carboxylic acids include trimellitic acid, pyromellitic acid, and polyvalent carboxylic acids such as anhydrides thereof. Examples of polyhydric alcohols include trimethylolpropane, pentaerythritol, and
Examples thereof include glycerin. When the component (C) is a polyvalent carboxylic acid, the total amount of the components (A) and (C) is 0.1 to 0.1
5 mol%, (B) component and (C) in the case of polyhydric alcohol
The range of 0.1 to 5 mol% in the total amount of the components is preferable. If it is lower than this range, the compounding effect is not obtained, and if it is higher than this range, the reaction tends to be difficult to control due to gelation. More preferably, it is in the range of 0.3 to 2 mol%.

The component (D) of the present invention is a heat resistance imparting component and is 3 to 6 relative to the total of the components (A), (B) and (C).
It is preferably 5% by weight. If the content is less than 3% by weight, flexibility and rubber elasticity are insufficient, and if it exceeds 65% by weight, the polycondensation reaction tends to be stagnant and the moldability tends to be poor. A more preferable addition range is 10 to 50% by weight. In the unit in the compound of the component (D), m is 2
It is preferably 6 or more and 6 or less, and n is preferably 4 or more and 23 or less. If m is less than 2, the mechanical properties of the resulting resin will be insufficient, and if m is greater than 6, the heat resistance will be insufficient. Also, when n is less than 4, mechanical properties of the obtained resin are insufficient, and when n is greater than 23, transparency and appearance may be insufficient. The compound as the component (D) preferably has an average molecular weight of 500 to 2000. If the average molecular weight is less than 500, the resulting resin has insufficient mechanical properties, and if it is greater than 2000, the transparency and appearance may be insufficient. The component (D) of the present invention may be added at any time during the polymerization reaction, but is preferably after the esterification reaction of the components (A) to (C). This is because the component (D) has a carbonate bond and may be randomized by transesterification.

As the method for obtaining the polyester resin of the present invention, the known direct polymerization method, transesterification method or the like can be used. The polymerization degree is preferably such that the intrinsic viscosity η measured in a mixed solvent of phenol / tetrachloroethane at 25 ° C. is 0.5 dl / g or more, more preferably 0.6 dl / g or more. Is more preferable. If it is less than 0.5 dl / g, the viscosity is low,
It is difficult to cool the strands, and the loss during pelletizing tends to be large. Further, as a method for obtaining the molded article of the present invention, injection molding, ordinary molding methods such as extrusion molding,
Conditions can be adopted, and the molded product can be molded into various applications such as pellets, films, sheets and fibers. A molded product using the polyester resin composition of the present invention may be subjected to various well-known processing treatments in order to impart further specific performance, or may be blended with suitable additives. Examples of processing treatment include irradiation with ultraviolet rays, α rays, β rays, γ rays or electron rays, corona treatment, plasma irradiation treatment, flame treatment and the like, vinylidene chloride, polyvinyl alcohol, polyamide, polyolefin and other resins. Examples include coating, laminating, vapor deposition of metal, and the like.
Examples of additives include polyether, polyamide, polyolefin, resins such as polymethylmethacrylate, silica, talc, kaolin, inorganic particles such as calcium carbonate,
Examples thereof include pigments such as titanium oxide and carbon black, ultraviolet absorbers, release agents, antistatic agents, flame retardants and the like.

[0010]

EXAMPLES The present invention will be specifically described below with reference to examples. [Example 1] 668.2 g of terephthalic acid, 301.3 g of ethylene glycol and 3.9 g of trimellitic anhydride were placed in a reaction vessel, and the mixture was heated and stirred at 190 to 225 ° C for 3 hours to carry out an esterification reaction. Then, the temperature was raised to 245 ° C., 100 g of polyhexamethylene polycarbonate having an average molecular weight of 1000, and 0.3 g of antimony trioxide as a polymerization catalyst.
Was added to proceed the polymerization reaction. The intrinsic viscosity η of the obtained polyester resin measured in a mixed solvent of phenol / tetrachloroethane at 25 ° C. was 0.74. This resin and pellets dried at 80 ° C. for 8 hours were injection molded from ASTM-D638 test pieces at 200 ° C., and were used for Shore A hardness, tensile strength and elongation, high temperature shape retention, and molded product appearance (resistance The chemical property) was evaluated.
The evaluation results are shown in Table 1. The evaluation methods are as follows. Shore A hardness: According to ASTM-K7215. Tensile strength and elongation: According to ASTM-D638. High temperature shape retention: 1 at room temperature by dynamic elastic modulus measurement by DMS
The change in elastic modulus at 70 ° C. was calculated based on the following equation. (Dynamic elastic modulus at 170 ° C.) / (Dynamic elastic modulus at 23 ° C.) ×
100% molded product appearance (chemical resistance): The surface of a sheet having a thickness of 200 μm at 23 ° C. was rubbed with acetone, and the change in appearance was visually evaluated.

[Example 2] 385.5 g of terephthalic acid,
173.8 g of ethylene glycol and 2.2 g of trimellitic anhydride were placed in a reaction vessel to carry out an esterification reaction. Then, 500 g of polyhexamethylene polycarbonate having an average molecular weight of 1000 and 0.2 g of antimony trioxide as a polymerization catalyst were added to proceed the polymerization reaction. The obtained polyester resin had an intrinsic viscosity η = 0.74. Table 1 shows the evaluation results of this resin and the injection molded test piece. [Example 3] Dimethyl terephthalate 490.2 g, 1,4
-Butanediol 545.9 g, trimethylolpropane 6.8 g, tetra-n-butoxytitanium as a catalyst
34 g was placed in a reaction vessel to carry out a transesterification reaction. Next, 400 g of polyhexamethylene polycarbonate having an average molecular weight of 500 was added to allow the polymerization reaction to proceed. The obtained polyester resin had an intrinsic viscosity η = 0.74.
The results of evaluating this resin in the same manner as in Example 1 are shown in Table 1.

[Example 4] Dimethyl terephthalate 49
0.2 g, 545.9 g of 1,4-butanediol, 6.8 g of trimethylolpropane and 0.34 g of tetra-n-butoxytitanium as a catalyst were placed in a reaction vessel to carry out a transesterification reaction. Next, 400 g of polyhexamethylene polycarbonate having an average molecular weight of 2000 was added to allow the polymerization reaction to proceed. The obtained polyester resin has an intrinsic viscosity η =
It was 0.88. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 1. [Example 5] Dimethyl naphthalene dicarboxylate 433.
4 g, 274.1 g of ethylene glycol, 12.4 g of trimellitic anhydride, and 0.2 g of manganese acetate as an ester exchange catalyst were placed in a reaction vessel for transesterification reaction, and then 500 g of polytrimethylene polycarbonate having an average molecular weight of 1000 and phosphorus. The polymerization reaction was allowed to proceed by adding 0.04 g of an acid and 0.2 g of germanium dioxide as a polymerization catalyst. The obtained polyester resin has an intrinsic viscosity η = 0.
It was 60. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 1.

[0013]

[Table 1]

Comparative Example 1 Dimethyl terephthalate 100
2 g, ethylene glycol 772.7 g, trimellitic anhydride 5.0 g, and manganese acetate 0.4 g as a transesterification catalyst were placed in a reaction vessel, and after transesterification, phosphoric acid was 0.1 liter.
g, and 0.4 g of germanium dioxide as a polymerization catalyst were added to proceed the polymerization reaction. The obtained polyethylene terephthalate had an intrinsic viscosity η = 0.78. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2. [Comparative Example 2] 879.9 g of dimethyl terephthalate, 1,4
-Butanediol 980.0 g, trimethylolpropane 3.0 g, tetra-n-butoxytitanium as catalyst 0.0.
6 g was placed in a reaction vessel to carry out transesterification and polymerization reaction. The obtained polybutylene terephthalate had an intrinsic viscosity η = 0.96. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2.

[Comparative Example 3] 102.4 g of terephthalic acid,
Ethylene glycol (46.0 g) and trimethylolpropane (1.7 g) were placed in a reaction vessel, and an esterification reaction was performed. Then, 800 g of polytetramethylene glycol having an average molecular weight of 1000 and antimony trioxide (0.1 g) as a polymerization catalyst were used.
g was added to allow the polymerization reaction to proceed. The obtained polyester resin had an intrinsic viscosity η = 0.74. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2. [Comparative Example 4] 478.0 g of terephthalic acid, 214.4 g of ethylene glycol, and 7.7 g of trimethylolpropane were placed in a reaction vessel, an esterification reaction was carried out, and then polyhexamethylene polycarbonate having an average molecular weight of 3000 was added to 4 parts.
The polymerization reaction was allowed to proceed by adding 00 g and 0.2 g of antimony trioxide as a polymerization catalyst. The obtained polyester resin had an intrinsic viscosity η = 0.62. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2. [Comparative Example 5] 478.0 g of terephthalic acid, 214.4 g of ethylene glycol, and 7.7 g of trimethylolpropane were placed in a reaction vessel, an esterification reaction was carried out, and then 500 parts of polytrimethylene polycarbonate having an average molecular weight of 200 were added.
g, and 0.2 g of antimony trioxide as a polymerization catalyst were added to proceed the polymerization reaction. The obtained polyester resin had an intrinsic viscosity η = 0.96. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2.

[Comparative Example 6] Dimethyl terephthalate 49
1.9 g, 1,4-butanediol 547.9 g, trimethylolpropane 3.4 g, and tetra-n-ptoxytitanium 0.3 g as a catalyst were placed in a reaction vessel to carry out transesterification reaction, and then polytetratetrahydrofuran having an average molecular weight of 1,000 was used. 400 g of methylene glycol was added to proceed the polymerization reaction. The obtained polyester resin has an intrinsic viscosity η = 0.74.
Met. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2. [Comparative Example 7] 579.0 g of terephthalic acid and 303.1 g of ethylene glycol were placed in a reaction vessel and subjected to an esterification reaction, then 300 g of polyhexamethylene polycarbonate having an average molecular weight of 1000 and 0.2 g of antimony trioxide as a polymerization catalyst. Was added to proceed the polymerization reaction. The obtained polyester resin had an intrinsic viscosity η = 0.74. The results of evaluating this resin in the same manner as in Example 1 are shown in Table 2.

[0017]

[Table 2]

[0018]

The polyester resin of the present invention maintains the excellent physical properties and molding processability of conventional polyester resins,
In addition to being a material with excellent flexibility, it has heat resistance, chemical resistance, high elasticity and high elastic recovery rate, and these physical properties do not deteriorate even at high temperatures, and surface gloss and mechanical properties It has excellent properties such as durability, and can be widely used for bottles, films, sheets, plates, fibers, and also for automobile parts, exterior parts, office equipment housings, and the like.

Claims (2)

(57) [Claims] 1. A dicarboxylic acid or an ester-forming derivative thereof, (B) a glycol or an ester-forming derivative thereof, and (C) a trivalent or higher polyvalent carboxylic acid, a polyhydric alcohol or an ester-forming derivative thereof. In the case of polyhydric carboxylic acid, 0.1 to 5 mol% in the total amount of components (A) and (C), and in the case of polyhydric alcohol, 0.1 in the total amount of components (B) and (C). A polyester resin comprising 1 to 5 mol% and (D) a compound having a unit represented by the following general formula in an amount of 3 to 65% by weight based on the total of the components (A) to (C). , A polyester resin having an intrinsic viscosity η of 0.5 dl / g or more measured in a mixed solvent of phenol / tetrachloroethane at 25 ° C. [Chemical 1] (However, 2 ≦ m ≦ 6, 4 ≦ n ≦ 23) 2. A molded product comprising the polyester resin according to claim 1.