JPH09100342A - Polyester resin and sheet using the same - Google Patents

Abstract

(57) [PROBLEMS] To provide a polyester resin having a high crystallization temperature without impairing heat resistance and having good transparency. SOLUTION: This is obtained by reacting terephthalic acid or its ester-forming derivative with ethylene glycol in the presence of a polymerization catalyst consisting of a specific amount of germanium oxide and antimony trioxide, and a stabilizer consisting of a specific amount of a phosphorus compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyester resin and a sheet using the same.

[0002]

[Prior Art] Polyester resin has excellent properties such as mechanical properties, chemical resistance, gas barrier properties, transparency, and safety, so that it is used for automobile parts, electric / electronic parts, and other mechanical parts. It is applied to many uses such as A-PET (amorphous sheet).

However, the polyester resin has a property of being whitened by crystallization and has a problem of impairing excellent transparency. Therefore, some methods have been developed for delaying the crystallization of the polyester resin. ing. For example, when the polyester resin is polyethylene terephthalate, terephthalic acid as the dicarboxylic acid component is replaced with isophthalic acid, and ethylene glycol as the glycol component is replaced with neopentyl glycol to disrupt the symmetry of the primary structure and delay the crystallization rate. The method of making it proposed is proposed.

However, in the method of changing the primary structure, the melting point is lowered at the same time as the crystallization rate is delayed, and in many cases, the glass transition temperature is also lowered, which impairs the excellent heat resistance of the polyester resin. There is a problem. Further, as a method of not lowering the heat resistance, there has been proposed a method of adding an amorphous resin to a polyester resin, in particular, in this case, a polycarbonate having excellent compatibility with the polyester resin (JP-A-3-20).
No. 7750), although a tentative effect can be recognized by delaying the crystallization rate without lowering the heat resistance by such a method, it has not yet reached a point where a sufficient practical effect is obtained. is there.

[0005]

The object of the present invention is to improve the above-mentioned drawbacks of the prior art, without impairing the heat resistance,
Another object of the present invention is to provide a more economically advantageous polyester resin having a delayed crystallization rate.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have used a specific amount of a specific polymerization catalyst and a stabilizer when obtaining a polyester resin, The present invention has been accomplished by finding that a polyester resin having specific physical properties can achieve the above object.

That is, the present invention relates to a polymerization catalyst comprising terephthalic acid or an ester-forming derivative thereof and ethylene glycol in an amount satisfying the following formulas (I) to (V), and a phosphorus compound and a phosphorus compound. A polyester resin obtained by reacting in the presence of a stabilizer, and having an intrinsic viscosity of 0.5 dl / g or more.

10 <Ge <40 (I) 0 ≦ Sb <50 (II) 10 <(1.37 × Sb) + Ge <93 (III) 0 ≦ Sb / Ge <5 (IV) 0 ≦ P <1. 0 (V) (However, Ge, Sb in the above formulas (I) to (V),
P represents the number of moles per 10 ⁶ g of polyester produced. )

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester resin of the present invention comprises a terephthalic acid or an ester-forming derivative thereof, such as dimethyl terephthalic acid, diethyl terephthalic acid, dibutyl terephthalic acid, etc., and ethylene glycol, for example, by an ester exchange method or an esterification method. Manufactured by the polymerization of.

In the transesterification method, the above-mentioned monomers are charged into a reaction vessel and the reaction is carried out in the presence of a known transesterification catalyst.
After reacting at 0 ° C to 250 ° C, a stabilizer, a polymerization catalyst and the like are added and 260 ° C to 300 ° C under reduced pressure of 5 mmHg or less.
It can be obtained by heating to room temperature and reacting for 3 to 5 hours.

In the esterification method, the above monomers are charged in a reaction vessel to carry out an esterification reaction at 150 ° C. to 260 ° C. under nitrogen pressure, and after completion of the esterification reaction, stabilizers, polymerization catalysts, etc. are added to obtain an amount of 5 mmHg or less. 260 ° C under reduced pressure
It can be obtained by heating to ˜300 ° C. and reacting for 3 to 5 hours.

The polymerization catalyst used in the polymerization comprises germanium oxide such as germanium dioxide alone or a combination system of germanium oxide and antimony trioxide. The amount of germanium oxide used alone is within the range of the above formula (I) 10 <Ge <40 with respect to 10 ⁶ g of polyester produced in the number of moles of germanium (Ge), and the amount of germanium oxide used is If the amount is out of the above range, the degree of polymerization is difficult to increase, and thus a long reaction time is required, resulting in deterioration of physical properties due to side reaction products and deterioration of hue such as yellowing.

When antimony trioxide is used in combination as a polymerization catalyst, the amounts of germanium oxide and antimony trioxide used are within the ranges satisfying the above formulas (I) to (IV). When the amount of antimony trioxide used exceeds the above range, the effect of retarding the crystallization rate is reduced and the transparency is deteriorated.

In the polymerization, other catalysts may be used in combination with the above-mentioned polymerization catalyst, if necessary. As an example, for example, dibutyltin oxide,
Tin compounds such as n-butyl hydroxytin oxide; zinc, manganese, lead carboxylic acids such as zinc acetate, manganese acetate and lead acetate;
Mention may be made of alkali metal compounds such as sodium or potassium hydroxide and potassium acetate; magnesium or calcium hydroxide; and alkaline earth metal compounds such as calcium acetate.

The polymerization catalyst in the present invention may be added before the esterification reaction starts, during the reaction, or after the reaction, that is, before the polycondensation reaction.

The phosphorus compound used as the stabilizer in the present invention is a phosphorus-based heat stabilizer, and examples thereof include phosphoric acid, phosphorous acid, metaphosphoric acid, trimethyl phosphate, triethyl phosphate, triphenyl phosphate, and triphenyl phosphate. Examples thereof include octyl phosphate, dimethyl phosphite, diethyl phosphite, dicyclohexyl phosphite, diphenyl phosphite, dioctyl phosphite, dimethylpyrophosphate, diethylpyrophosphate, diphenylpyrophosphate, dicyclohexylpyrophosphate and dioctylpyrophosphate.

The amount of the phosphorus compound used is in the range of 0 ≦ P <1.0 of the above formula (V) per 10 ⁶ g of polyester produced in the number of moles of phosphorus (P), and if it is out of this range, crystallization occurs. The speed delay effect cannot be obtained.

The phosphorus compound may be added at any time after the esterification, but it is preferable to add it at the same time as the polymerization catalyst.

The polyester resin of the present invention obtained by the above constitution is phenol / 1,1,2,2-
It is necessary that the intrinsic viscosity in a tetrachloroethane equivalent mixture solution is 0.5 dl / g or more when measured at 25 ° C. This is because sufficient strength cannot be obtained when a molded product such as a sheet is formed using a polyester resin having an intrinsic viscosity of less than 0.5 dl / g.

Further, the polyester resin of the present invention has a JI
The b value measured according to S-Z-8722 is less than 6, and the crystallization temperature (hereinafter abbreviated as Tc ⁺ ) and the glass transition temperature (hereinafter abbreviated as Tc ⁺ ) measured by a differential scanning calorimeter (DSC). , Tg). ΔT (Tc ⁺ −T
g) is preferably 60 ° C. or higher. This is because when the b value is 6 or more, the yellowness of the obtained molded product becomes conspicuous,
Further, the difference ΔT (Tc ⁺ −Tg) between Tc ⁺ and Tg is 60.
This is because if the temperature is lower than ° C, the effect of delaying the crystallization rate is not sufficient, and the crystallization causes the transparency to decrease.

The polyester resin of the present invention includes, for example, Irganox 1010, Irganox 1076, Irganox 1 within a range not departing from the object of the present invention.
Antioxidants such as 098 (product of Ciba Geigy), color retention agents such as cobalt acetate, UV absorbers such as benzotriazole, softening point lowering agents such as triethylamine, quenchers such as titanium oxide, silica,
Inorganic particles such as talc, kaolin, calcium carbonate,
A pigment such as titanium oxide or carbon black, a dye, a fluorescent whitening agent, an antistatic agent, a release agent, and a flame retardant may be added.

The sheet of the present invention is vacuum-dried by a known method, for example, the above polyester resin at 120 to 140 ° C. for 5 to 8 hours, and the temperature of the cylinder is 260 to 280 ° C. and the die temperature is 275 using a commonly used film forming machine. Extrusion at ~ 290 ° C gives a sheet with a thickness of 0.1-1 mm.

[0023]

The present invention will be described below in detail with reference to examples and comparative examples. The physical properties used in the examples were determined by the methods described below.

(1) Intrinsic viscosity The polymer was dissolved in 1 dl of an equal weight mixed solvent of phenol and 1,1,2,2-tetrachloroethane and measured at 25 ° C.

(2) Measurement of glass transition temperature (Tg), crystallization temperature (Tc ⁺ ) and melting point (Tm) Using a differential scanning calorimeter (DSC) (manufactured by Shimadzu Corporation),
A sample melt-quenched at 280 ° C. in a nitrogen stream was heated to 280 ° C. at a rate of 5 ° C./min.
Measured by cooling at ℃ / min, Tg is shoulder value, Tc
⁺ And Tm have peak values.

Examples 1 to 5 and Comparative Examples 1 to 5 100 parts by mole of terephthalic acid and 140 parts by mole of ethylene glycol were placed in a reaction vessel, and the polymerization catalyst and phosphorus compound (stabilizer) shown in Table 1 were added. While gradually reducing the pressure, the temperature was raised to 290 ° C., and the polycondensation reaction was performed under a reduced pressure of 5 mmHg or less to obtain a polyester resin having a predetermined polymerization degree.

Next, the obtained polyester resin was vacuum dried to a water content of 100 ppm or less and then formed into a film with a film forming machine to obtain a sheet having a thickness of 250 μm.
Table 1 shows the measurement results of the physical properties of the obtained sheet.

Example 6 Dimethyl terephthalate 100
Add 240 parts by mole of ethylene glycol to a reaction vessel, and add 400 p of manganese acetate as a transesterification catalyst.
pm (amount of acid component) was added, and the temperature was gradually raised to 130 ° C. to carry out a transesterification reaction. After transesterification, Table 1
The polymerization catalyst and phosphorus compound (stabilizer) shown in are added,
While gradually reducing the pressure, the temperature was raised to 290 ° C., and the polycondensation reaction was performed under a reduced pressure of 5 mmHg or less to obtain a polyester resin having a predetermined polymerization degree.

The polyester resin thus obtained has a water content of 10
After vacuum drying so as to be 0 ppm or less, a film was formed by a film forming machine to obtain a sheet having a thickness of 250 μm. Table 1 shows the measurement results of the physical properties of the obtained sheet.

[0030]

[Table 1]

[0031]

INDUSTRIAL APPLICABILITY The polyester resin of the present invention retains a high crystallization temperature without impairing heat resistance, and has excellent properties as a polyester resin such as transparency and gas barrier property, and therefore is suitable for packaging. It can be widely used as a polyester sheet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seisuke Tanaka 2-4-1, Ushikawa-dori, Toyohashi-shi, Aichi Sanryo Rayon Co., Ltd. Toyohashi Plant

Claims (3)

[Claims] 1. Terephthalic acid or an ester-forming derivative thereof and ethylene glycol are represented by the following formulas (I) to (V):
Obtained by reacting in the presence of a polymerization catalyst consisting of germanium oxide and antimony trioxide, and a stabilizer consisting of a phosphorus compound, and having an intrinsic viscosity of 0.5.
A polyester resin having a dl / g or more. 10 <Ge <40 (I) 0 ≦ Sb <50 (II) 10 <(1.37 × Sb) + Ge <93 (III) 0 ≦ Sb / Ge <5 (IV) 0 ≦ P <1.0 (V (However, Ge, Sb in the above formulas (I) to (V),
P represents the number of moles per 10 ⁶ g of polyester produced. ) 2. The b value measured according to JIS-Z-8722 is less than 6, and the difference ΔT (Tc ⁺ -Tg) between the crystallization temperature (Tc ⁺ ) and the glass transition temperature (Tg) is 6
The polyester resin according to claim 1, which has a temperature of 0 ° C or higher. 3. A sheet made of the polyester resin according to claim 1 or 2.