JP2973454B2 - Polyester production method - Google Patents

Description

The present invention relates to a method for producing a polyester. More specifically, the present invention relates to a method for producing a polyester having excellent transparency and antistatic properties. More specifically, to improve the transparency and antistatic properties of fibers, films, sheets and other molded products obtained from polyester. And a method for producing a polyester.

[Prior Art] As is well known, polyesters, in particular, polyalkylene terephthalate represented by polyethylene terephthalate and polybutylene terephthalate, or poly-1,4-cyclohexane dimethylene terephthalate and polyesters based thereon are various excellent physical properties. It has chemical properties and is widely used in fibers, films, sheets or other molded products. However, since the polyester is easily charged with static electricity, there is a disadvantage that various troubles are liable to occur during a manufacturing process of a fiber, a film, or other molded products, or at the time of using the product.

Conventionally, it has been proposed to blend various metal sulfonic acid compounds with various metal compounds or polyoxyalkylene glycols for the purpose of imparting antistatic properties to polyester. For example, JP-A-50-53465 and JP-A-52-134662 disclose simply mixing a metal sulfonic acid compound into polyester, and JP-A-54-6049 discloses a metal sulfonic acid compound. And halides or sulfates of alkali metals and alkaline earth metals, JP-A-60-38
No. 123 discloses that a metal salt of a sulfonic acid and a metal salt of a higher fatty acid are compounded in polyester. However, in these methods, the antistatic performance of the polyester is insufficient, and the compatibility of the sulfonic acid metal salt compound with the polyester is not sufficient, or fibers or films obtained due to other metal salt compounds to be blended. However, there are drawbacks such as formation of coarse surface projections on the sheet or other molded product, and remarkable loss of transparency. Japanese Patent Publication No. 44-31828 discloses an example in which a polyoxyalkylene glycol is substantially used. However, in this case, the obtained polyester is cloudy and has poor transparency, which is not preferable. Further, JP-A-52-47069,
JP-A-52-47072 exemplifies a film made of a composition of a metal sulfonic acid compound and a polyoxyalkylene glycol having a molecular weight of 400 to 8,000. In this case, a certain degree of antistatic property can be imparted, but there is a disadvantage that the transparency of the film is inferior.

[Problems to be Solved by the Invention] The inventors of the present invention have made intensive studies to solve the above problems, and as a result, have reached the present invention.

That is, an object of the present invention is to provide a polyester production method for improving surface defects, transparency, and antistatic properties of fibers, films, sheets or other molded products obtained from polyester.

[Means for Solving the Problems] The object of the present invention is to produce a polyester by reacting a carboxylic acid component or an ester-forming derivative thereof with a glycol component. 20.0% by weight
R: SO ₃ Mm R: Alkyl aryl group M: Alkali metal or alkaline earth metal m: 1 or 1/2 of sulfonic acid metal salt compound and (b) the sulfonic acid metal salt compound 2.0-50 mol% of alkali metals, alkaline earth metals, Mn, Zn and Co
Glycol-soluble metal compounds containing at least one metal element selected from (excluding alkali metal salts of alkylsulfonic acids) (hereinafter also referred to as metal compounds)
Can be added to the reaction system at any stage of the polyester production process.

The polyester of the present invention refers to a polyester produced by a transesterification or esterification reaction between a dicarboxylic acid or an ester-forming derivative thereof and a glycol component, and a polycondensation reaction. The type of polyester is not particularly limited as long as it can be formed into fibers, films, sheets or other molded products. Examples of the dicarboxylic acid or its ester-forming derivative used in the present invention include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among them, aromatic dicarboxylic acids are preferred. In addition, examples of the glycol component include aliphatic and alicyclic glycols. Preferred polyesters obtained from the above components include polyethylene terephthalate,
Polybutylene terephthalate, polyhexylene terephthalate, polyethylene-P-oxybenzoate, polyethylene-1,2-bis (2-chlorophenoxy) ethane-4,4'-dicarboxylate, polyethylene-1,2-bis (2 -Phenoxy) ethane-4,4'-dicarboxylate, polyethylene-2,6-naphthalene dicarboxylate, polyethylene isophthalate, poly-1,4-cyclohexane dimethylene terephthalate and the like. Among them, polyethylene terephthalate is preferred.

Of course, these polyesters may be homopolyesters or copolyesters. As components to be copolymerized, for example, diethylene glycol, neopentyl glycol, p-xylylene glycol, 1-4
Diol components such as cyclohexanedimethanol and 5-sodium sulforesorcin; dicarboxylic acid components such as dipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid and 5-sodium sulfoisophthalic acid; and trimellitic acid And polyfunctional carboxylic acid components such as pyromellitic acid, and oxycarboxylic acid components such as p-oxyethoxybenzoic acid.

In order to produce a polyester comprising the dicarboxylic acid or its ester-forming derivative and a glycol component, any method is employed. For example, in the case of producing polyethylene terephthalate, a direct esterification reaction between terephthalic acid and ethylene glycol or a transesterification reaction between dimethyl terephthalate and ethylene glycol is performed to prepare a glycol ester of terephthalic acid or a low polymer thereof. It is most commonly produced by a first-stage reaction to be produced and a second stage in which the first-stage reaction product is subjected to a polycondensation reaction. Further, in the present invention, a suitable amount of an alkali metal such as lithium, sodium, and potassium, an alkaline earth metal such as calcium, magnesium, strontium, and barium and zinc, manganese, and the like for the esterification reaction or the transesterification reaction.
Hydrates such as cobalt, alcoholates, chlorins and glycol-soluble salts of monocarboxylic acids, and titanium compounds and tin compounds are preferably used as catalysts. Particularly preferred are lithium acetate, sodium acetate, calcium acetate, magnesium acetate, zinc acetate, manganese acetate, manganese chloride and the like. A typical catalyst used in the polycondensation reaction is an antimony or germanium compound soluble in glycol, and specifically, antimony trioxide, germanium oxide and the like are preferable. Further, a titanium compound may be used. In addition, phosphorus compounds as various color inhibitors generally used in the production of polyesters can also be preferably used. Examples of the phosphorus compounds include phosphoric acid, phosphorous acid, phosphonic acid, and derivatives thereof. Specific examples include phosphoric acid, phosphorous acid, trinyl phosphate, tributyl phosphate, triphenyl phosphate, mono- or dimethyl phosphate, dimethyl phenylphosphonate, diethyl phenylphosphonate, and the like. Can be. Further, these catalysts and color inhibitors may be used alone or in combination of two or more.

The sulfonic acid metal salt compound of the present invention is represented by the following formula.

R—SO ₃ Mm R: alkylaryl group M: alkali metal or alkaline earth metal m: 1 or 1/2 alkylaryl group R of the sulfonic acid metal salt compound
May have a linear or branched side chain. In particular, when added to polyester, R must be a metal sulfonate compound which is an alkylaryl group from the viewpoint of compatibility. In this case, the number of carbon atoms is preferably 5 to 40, particularly preferably 8 to 30. M is an alkali metal such as Na, K, Li, or
Examples thereof include alkaline earth metals such as Mg and Ca. Especially
Na, K and Li are preferred.

Specific examples of such sulfonic acid metal salt compounds include sodium dodecylbenzenesulfonate, sodium stearylbenzenesulfonate, sodium octylbenzenesulfonate, potassium dodecylbenzenesulfonate, lithium dodecylbenzenesulfonate, sodium octylnaphthalenesulfonate, Examples thereof include sodium dodecylnaphthalenesulfonate and potassium dodecylnaphthalenesulfonate. Of these, sodium dodecylbenzenesulfonate is preferred.

The amount of the sulfonic acid metal salt compound of the present invention needs to be 0.01 to 20.0% by weight based on the obtained polyester. Preferably, it is 0.05-15.0% by weight, more preferably 0.1-10.0% by weight. If the amount of the sulfonic acid metal salt compound is less than 0.01% by weight, the antistatic performance of the polyester is not sufficient. On the other hand, if it exceeds 20% by weight, the softening point, color tone, mechanical properties and heat resistance of the polyester are undesirably reduced. . The resulting molded product is colored, which impairs commercial value. When the sulfonic acid metal salt compound is added to the polyester, it may be in the form of powder, solid, or water and / or glycol solution, and is not particularly limited.

In the present invention, an alkali metal and an alkaline earth metal, a metal compound containing a metal element selected from Mn, Zn and Co must be glycol-soluble, preferably ethylene glycol used during a polyester synthesis reaction, butanediol, A glycol-soluble metal compound such as cyclohexanedimethanol is preferred, and an ethylene glycol-soluble metal compound is particularly preferred. If the metal compound is glycol-insoluble, the compatibility of the sulfonic acid metal salt compound with the polyester cannot be improved,
Further, the metal compound becomes a foreign substance in the polyester, and the transparency of the obtained molded product cannot be improved.

Specific examples of glycol-soluble metal compounds include alkali metals and alkaline earth metals, oxides, hydrides, acetates, hydroxides, alcoholates, glycolates and the like of Mn, Zn and Co. Among these metal compounds, acetates or hydroxides of Li, K, Na, Ca, Mn, Zn or Co are preferred, and among them, acetates or hydroxides of Li, Na, Ca, Mn are preferred. Particularly, acetates or hydroxides of Li, Ca, and Mn are preferable. One of these metal compounds may be used alone, or two or more thereof may be used in combination.

The addition amount of the glycol soluble metal compound to the polyester of the present invention, it is necessary to add 2.0 to 50.0 mol% with respect to sulfonic acid metal salt compound represented by the formula R-SO ₃ Mm. Preferably from 3.0 to 40 mol%, more preferably
It is 5.0 to 30 mol%.

The amount of the glycol-soluble metal compound added to the polyester is suitably in the range of 0.005 to 4.0 parts by weight, preferably 0.01 to 2.0 parts by weight, more preferably 0.0 to 2.0 parts by weight.
5 to 1.5 parts by weight.

If the amount of the glycol-soluble metal compound added to the polyester is less than 2.0 mol% based on the metal sulfonic acid compound, the compatibility of the metal sulfonic acid compound with the polyester is insufficient, and the polyester is opaque and has a rough surface. And the surface defects and transparency of the obtained molded product cannot be improved. Furthermore, the antistatic performance of polyester is not sufficient. On the other hand, if it exceeds 50.0 mol%, coarse foreign substances are generated in the polyester, the heat resistance is reduced, and the polyester is markedly colored. When the glycol-soluble metal compound is added to the polyester, it is preferably in the form of powder, solid, or water or glycol solution.
Further, the addition may be continuous, and may be added all at once or dividedly.

Further, in the present invention, a sulfonic acid metal salt compound represented by R-SO ₃ Mm and an alkali metal, an alkaline earth metal, M
The method of adding the glycol-soluble metal compound containing at least one metal element selected from n, Zn and Co to the polyester is not particularly limited. It may be added before the esterification or transesterification reaction in the polyester production step, or during or after the reaction, before the polycondensation reaction, or during the reaction or in the molten state after the reaction. Preferably, it is added at any stage from the transesterification reaction or the esterification reaction to the end of the polycondensation reaction in the polyester production process, and a polyester excellent in compatibility and transparency of the sulfonic acid metal salt compound to the polyester is used. The best way to obtain it is to add it at any stage from the end of the transesterification or esterification reaction in the polyester production process to the beginning of the polycondensation reaction. The order of addition is not particularly limited, and may be any order of addition, or may be mixed.

The polyester obtained in the present invention can be used as a master polymer by blending it with ordinary polyester.

Furthermore, in order to further improve the transparency and antistatic property of the present invention, polyoxyalkylene glycols and the like can also be preferably used. Examples of the polyoxyalkylene glycol include polyethylene glycol having a molecular weight of 300 or more, polypropylene glycol, and polytetraalkylene glycol. Methylene glycol and the like can be mentioned. Such a polyoxyalkylene glycol may have one end or both ends blocked by an organic group having an ester-forming functional group such as an ester bond or a carbonate bond. The preferred molecular weight of the polyoxyalkylene glycol is 300 to 50000
And more preferably 500 to 20,000. Particularly preferred polyoxyalkylene glycols have a molecular weight of 60
0-10000 polyethylene glycol. The amount of these polyoxyalkylene glycols added is polyester
The range of 0.1 to 20.0% by weight relative to 100 parts by weight is appropriate, preferably 0.2 to 15.0% by weight, and more preferably 0.5 to 10.0% by weight. If the amount of the polyoxyalkylene glycol is less than 0.1% by weight, the antistatic effect is not sufficient, and if it exceeds 20.0% by weight, the softening point, color tone, mechanical properties and heat resistance of the polyester are undesirably reduced. The resulting molded product is colored, which impairs commercial value.

The method and timing of adding these polyoxyalkylene glycols to the polyester are arbitrary and not limited.

When producing the polyester by the production method of the present invention, organic compounds such as flame retardants, heat stabilizers, ultraviolet absorbers, pigments, dyes, fatty acid esters, waxes, etc. A lubricant, or an antifoaming agent such as polysiloxane may be added, and clay, mica, titanium oxide, calcium carbonate, and the like for the purpose of imparting gloss, matte, slipperiness, etc. of the molded product.
Inorganic particles such as kaolin, dry and wet silica, colloidal silica, calcium phosphate, barium sulfate, and alumina, as well as particles made of organic compounds containing silicon, acryl, styrene, and the like, may be added.

Fibers, films, sheets and other molded products can be produced from the polyester obtained by the polyester production method of the present invention according to a conventional method.

[Examples] Hereinafter, the present invention will be described in more detail with reference to Examples.

 The characteristics in the examples were measured as follows.

A. Compatibility of antistatic agent with polyester 20 mg of polyester was sandwiched between cover glasses, melt-pressed on a hot plate at 290 ° C, cooled, and then evaluated by microscopic observation.

 粗 No coarse substance of 5 μ or more was observed.

 粗 Coarse objects of 5μ or more are slightly observed.

 Many large objects of × 10 μ or more are observed.

B. Antistatic properties of polyester Using a Kawaguchi Electric MMA II-15 ultra-micro ammeter, 50μ thickness obtained from polyester containing antistatic agent
Was left for 1 hour at room temperature of 20 ° C. and humidity of 65%, and the surface resistivity of the film was measured.

C. Transparency of polyester ASTM film with a thickness of 50μ obtained from polyester
Film haze was measured according to -D-1003-59T.

Example 1 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, 0.09 parts by weight of calcium acetate as a transesterification catalyst, and 0.03 parts by weight of antimony trioxide as a polycondensation reaction catalyst were subjected to a transesterification reaction according to a standard method, followed by color prevention. 0.05 parts by weight of trimethyl phosphate was added as an agent. Next, 3.33% by weight of an ethylene glycol solution containing 30% by weight of sodium dodecylbenzenesulfonate was added to the obtained polyester, and then 15% by mole of calcium acetate monohydrate was added to sodium dodecylbenzenesulfonate. did. Thereafter, a polycondensation reaction was carried out at a high temperature under reduced pressure according to a conventional method to obtain a polyester. The intrinsic viscosity of the polyester measured at 25 ° C. using an O-chlorophenol solvent was 0.615. Also,
The softening point was 258.2 ° C. The obtained polyester is
The transparency was good, and when the compatibility of the antistatic agent with the polyester was observed, it was finely dispersed to about 2.5 μm.

The obtained polyester is dried, and dried with a film forming machine.
After film formation at 0 to 300 ° C, the longitudinal stretching ratio was 3.
After stretching by a factor of 2 and a transverse stretching ratio of 3.2, a heat treatment was performed at 210 ° C. to obtain a film having a thickness of 50 μm. The surface resistivity of the film was 7.2 × 10 ⁹ Ω and the film haze was 0.8%, and both the antistatic property and the transparency were excellent.

Comparative Example 1 In the same manner as in Example 1, a polyester and a film to which only a sodium dodecylbenzenesulfonate ethylene glycol solution was added were obtained.

The intrinsic viscosity of the obtained polyester is 0.611, the softening point is 2
It was cloudy at 53.8 ° C and the surface of the polyester was rough due to coarse projections. Observation of the compatibility of the antistatic agent with the polyester revealed a dispersion of 40 to 50 μm.

The surface resistivity of the film was 10.2 × 10 ¹⁰ Ω, and the film haze was 8.3%, which was poor in both antistatic properties and transparency. In addition, coarse protrusions appeared on the film surface.

Examples 2 to 8, Comparative Examples 2 to 4 As described in Table 1, in the same manner as in Example 1, a sulfonic acid metal salt compound, various metal salt compounds and the amounts added were changed to obtain polyesters and films. .

 Table 1 shows the results.

Examples 2 to 8 were within the scope of the present invention, and the compatibility of the antistatic agent with the polyester, the surface resistivity of the film, and the film haze were good.

On the other hand, in Comparative Example 2, the amount of the metal compound added to the amount of the sulfonic acid metal salt compound was out of the range of the present invention, the obtained polyester had a strong yellow tint, and the surface of the polyester was rough due to coarse projections, Observation of the compatibility with the polyester revealed a large number of needle-like coarse substances having a size of 20 to 40 μm. Further, both the surface resistivity and the film haze of the obtained film were poor. In Comparative Example 3, the amount of the metal sulfonic acid compound added was out of the range of the present invention,
The obtained polyester was strong in yellowish color, had a low softening point, and was poor in both the surface resistivity and the film haze of the obtained film. Comparative Example 4 uses glycol-insoluble calcium stearate in place of the glycol-soluble metal compound of the present invention. The obtained polyester is rough due to coarse projections on the surface, and the compatibility with the polyester is poor. Observed 30-50μ
Were observed, and the surface resistivity and film haze of the obtained film were poor.

Examples 9 to 11 As described in Table 2, the amount of the metal sulfonic acid compound was changed in the same manner as in Example 1, and various polyoxyalkylene glycols were added following the addition of the metal sulfonic acid compound. The resulting polyester was produced. A film was produced from the obtained polyester in the same manner as in Example 1.

 Table 2 shows the properties of various polyesters and films.

Both examples are within the scope of the present invention and the color tone of the polyester, the compatibility of the antistatic agent with the polyester,
In addition, both the surface resistivity and the film haze of the film were good.

[Effects of the Invention] As described above, the present invention relates to a method for preparing a sulfonic acid metal salt compound and an alkali metal, an alkaline earth metal, M
By adding a specific amount of a glycol-soluble metal compound containing at least one metal element selected from n, Zn, and Co (excluding an alkali metal salt of an alkylsulfonic acid), an antistatic agent which has not been obtained before can be obtained. A polyester excellent in compatibility with polyester and transparency can be obtained.

From the polyester obtained by the production method of the present invention, there is no surface defect, transparency, good antistatic fiber,
Films, sheets and other molded products are obtained.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-161823 (JP, A) JP-A-57-5748 (JP, A) JP-A-2-232257 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) C08G 63/00-63/91 C08L 67/00-67/08

Claims (1)

(57) [Claims] (1) In producing a polyester by reacting a carboxylic acid component or an ester-forming derivative thereof with a glycol component, (a) 0.01 to 20% by weight based on the obtained polyester of the following formula: R-SO ₃ Mm R : An alkylaryl group M: an alkali metal or alkaline earth metal m: a sulfonic acid metal salt compound represented by 1 or 1/2 and (b) 2.0 to 50 mol% of an alkali metal based on the sulfonic acid metal salt compound , Alkaline earth metals, Mn, Zn and Co
A polyester obtained by adding a glycol-soluble metal compound containing at least one metal element selected from the following (excluding an alkali metal salt of alkylsulfonic acid) to a reaction system at an arbitrary stage of the polyester production process. Manufacturing method.