JPS63113016A - Production of polyester - Google Patents

Abstract

PURPOSE:To obtain the titled polymer suitable as fibers, by finely dispersing inert inorganic fine particles subjected to specific surface treatment into a glycol in the presence of an alkali earth metallic compound, a phosphorus compound and an alkali compound to give glycol slurry and adding the glycol slurry to a polyester during polymerization reaction. CONSTITUTION:(A) Inert organic fine particles (e.g. polytetrafluoroethylene, etc. and/or (B) inert inorganic fine particles (e.g. silica, etc.) subjected to surface treatment by adsorption of an inorganic compound (e.g. acetic acid, etc.) (C) an alkaline earth metallic compound (e.g. beryllium chloride, etc.), (D) a phosphorus compound (e.g. phosphoric acid, etc.) and (E) an alkali compound (e.g. sodium hydroxide, etc.) are blended with ethylene glycol, etc., and finely dispersed by a homomixer, etc., to give slurry, which is added to a polyester during polymerization reaction at a stage of preferably <=0.2 intrinsic viscosity and polycondensation is carried out to give the aimed polymer.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing polyester,
More specifically, the present invention relates to a method for producing polyester in which inert fine particles having excellent affinity with polyester are uniformly dispersed.

[Prior Art] Polyester, especially polyethylene terephthalate, has excellent physical and chemical properties and is therefore widely used as fibers, films, and other molded products. However, contrary to its excellent properties, it has poor process passability in the molding process to obtain the above-mentioned molded products, poor slipperiness during processing processes such as surface treatment, and during handling of the product itself, resulting in poor workability and poor product quality. Undesirable troubles such as a decline in value will occur. In order to solve these problems, a method is generally used in which fine particles are incorporated into polyester to give uniform fine irregularities to the surface of the molded product, thereby improving the surface smoothness of the molded product. It is generally known to use inorganic fine particles that are insoluble and inert in polyester, such as calcium carbonate, titanium disonide, silica, tar, kaolin, etc., as fine particles for bending, and usually, fine particles are dispersed in polyester. In order to improve properties, a glycol slurry of fine particles is prepared and added to the polyester manufacturing process. However, it is well known that the surfaces of these inert inorganic fine particles generally have poor affinity for glycols and polyesters, resulting in agglomeration in slurry or during polyester production. If aggregated coarse particles are present in the slurry, the aggregated coarse particles will precipitate, making it impossible to obtain a uniform and stable slurry, which will not only make it difficult to measure and add slurry automatically, but also make it difficult for fine particles to be uniformly dispersed. It becomes difficult to produce polyester. Furthermore, the presence of aggregated coarse particles in the polymer causes yarn breakage during spinning, and also causes problems such as wear of the yarn guide and spinneret.

Furthermore, in film, coarse protrusions, fish eyes (
This may cause small corn-like defects).

Particularly when applied to a film for magnetic tape, it causes dropout (similar to magnetic recording) and a decrease in the S/N ratio. Therefore, the development of a technique for suppressing the formation of aggregated coarse particles in slurry and polyester has been awaited.

In order to solve this problem, a method using inert inorganic fine particles surface-treated with a compound (Japanese Patent Application Laid-open No. 50-8
3523-94623), a method using inert inorganic fine particles containing a specific phosphorus compound (Japanese Unexamined Patent Publication No. 53-94623)
JP-A No. 56-103236, JP-A-56-103236), and a method of using a dispersant when preparing a slurry of inert inorganic fine particles (JP-A-51-68695, JP-A-52-139).
192, JP 54-131694, JP 56-88426, and JP 45-2077.
5) have been proposed. However, although these methods are effective for improving the dispersibility of the slurry, the inert inorganic fine particles have poor affinity with polyester, so the effect of suppressing the formation of agglomerated coarse particles in polyester is not sufficient.

Therefore, a method has been proposed (Japanese Unexamined Patent Publication No. 71632/1983) in which inert inorganic fine particles are surface-treated while being crushed using a specific organic compound that has good affinity with polyester. However, these surface-treated inert inorganic fine particles have poor affinity with glycol and form agglomerated coarse particles in slurry.
The effect of suppressing the formation of aggregated coarse particles in ester is not sufficient. Therefore, there has been a long-awaited development of a slurry of inert fine particles that have good affinity with polyester, improved dispersibility in polyester, and a method for preventing reagglomeration.

[Problems to be Solved by the Invention] The purpose of the present invention is to improve the above-mentioned drawbacks of the prior art, prevent re-agglomeration of inert fine particles that have excellent affinity with polyester, and provide a slurry with excellent storage stability. The present invention provides a method for producing a polyester containing inert inorganic fine particles, which is added to a polyester production process and finely dispersed in a polymer, and which does not generate aggregated coarse particles.

[Means for Solving and Resolving the Problems] The object of the present invention described above is to produce polyester from a dicarboxylic acid component and glycol.

In the polyester manufacturing process, a glycol slurry is prepared by finely dispersing inert organic fine particles and/or inert inorganic fine particles whose surface has been treated with an organic compound along with an alkaline earth metal compound, a phosphorus compound, and an alkali compound. This can be achieved by a method for producing polyester characterized by adding .

The polyester in the present invention may be any polyester that can be molded into fibers, films, and other molded products, such as polyethylene terephthalate, 1,4-cyclohexane dimethylene terephthalate, and polytetramethylene terephthalate. , polyethylene-2,6-naphthalene dicarboxylate, and the like. Of course, these polyesters may be homopolyesters or copolyesters. ] In the case of polyester, the components to be copolymerized include dielene glycol, propylene glycol,
Examples include diol components such as polyalkylene glycol, and dicarboxylic acid components such as isophthalic acid, adipic acid, and 5-sodium sulfoisophthalic acid. After the esterification reaction with glycol when the dicarboxylic acid component is a dicarboxylic acid, or after the transesterification reaction with glycol when the dicarboxylic acid component is a dicarboxylic acid ester, the resulting prepolymer is polycondensed at high temperature under vacuum. It is made of polyester. Furthermore, the prepolymer itself can be used as a starting material for polycondensation.

The inert organic fine particles of the present invention include polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, polystyrene, styrene-divinylbenzene copolymer, polymethyl acrylate, methyl acrylate-styrene copolymer, etc. Polymer compounds such as magnesium stearate, phthalic acid 111'11, terephthalic acid 111'11, etc. are almost insoluble and inert to boron esters such as potassium levonates! (Refers to fine particles made of polymers. Inert particles are metal oxides such as titanium, silica, alumina, and zirconia, composite oxides such as kaolinite, talc, and zeolite, and lithium fluoride. , fluorides such as calcium fluoride, carbonates such as calcium carbonate, phosphates such as lithium phosphate, calcium phosphate, sulfates such as calcium sulfate, barium sulfate, and other inorganic compounds that are almost insoluble and inactive in polyesters. Refers to fine particles consisting of

Among the inorganic fine particles, calcium carbonate is particularly preferred.

In the present invention, it is necessary to surface-treat the inert inorganic fine particles using an organic compound. The organic compound to be surface treated here may be any compound containing a hydrocarbon group such as an alkyl group and/or an aryl group. Specifically, acetic acid, propionic acid, butyric acid, imbutyric acid, valeric acid, pivalic acid, myristic acid, palmitic acid, stearic acid,
Carboxylic acids such as adipic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, acrylic acid polymers, sodium propionate, calcium stearate, sodium adipate, calcium terephthalate, sodium polyacrylate, ammonium polyacrylate, etc. Carboxylic acid salt, isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate-1
~) Organic titanium compounds such as titanate, tetraisopropylbis(dioctylphosphite) titanate, isopropyltrioctanonyl titanate, dicumylphenyloxyacetate titanate, hexamethyldisilazane, trimedelmonochlorosilane, vinyltrichlorosilane, mercaptopropyltrimethoxy I can't believe it.

In the present invention, methods for surface treatment of inert inorganic fine particles using an organic compound include a method in which the organic compound is physically adsorbed on the surface of the inert inorganic fine particles, and a method in which the organic compound and the surface of the inert inorganic fine particles are directly adsorbed. Although there is a method of chemically adsorbing by reacting, a chemical method with good adsorption properties is preferable. For example, there is a method of surface treating inert inorganic fine particles in a solution containing an organic compound.

The blending ratio of the inert inorganic fine particles to the organic compound is preferably 0 to that of the inert inorganic fine particles in order to improve the affinity of the inert inorganic fine particles to polyester.

0001 to 50% by weight.

The average particle diameter of the inert inorganic fine particles is not particularly limited, but is preferably 10 μm or less, more preferably 5 μm in order to reduce yarn breakage during spinning and spinning and coarse protrusions on the film.
Hereinafter, a material of 3 μm or less is more preferably used. The average particle diameter herein means the "isomorphic diameter" of particles at a point of 501 t% of all measured particles. E.S.D.
"Sphe-ricol diameter" means the diameter of a sphere on a phantom particle having the same volume as the particle, and can be calculated from an electron micrograph of the particle or measurement by a conventional sedimentation method.

Examples of the medium for the glycol slurry of inert fine particles include ethylene glycol, propylene glycol, butylene glycol, and two or more of these may be used. It is preferable to use the same glycol as the one used as the raw material for polyester production, as this will cause less deterioration in the quality of the polyester, and is also desirable from the viewpoint of preventing process contamination and ease of operation. Further, it is desirable to use glycol in combination with a lower alcohol such as methanol or ethanol, or a low boiling point solvent such as water, toluene, xylene, or pentane, since this further improves the dispersibility of the slurry.

In the present invention, it is necessary to coexist an alkaline earth metal compound, a phosphorus compound, and an alkali compound in the glycol slurry of inert fine particles.

The alkaline earth metal compounds used in the present invention include glycol-soluble halogen compounds, nitrates, perchlorates,
Examples include carboxylic acid salts, and specifically, beryllium chloride, magnesium chloride, calcium bromide, strontium bromide, barium iodide, magnesium nitrate, calcium nitrate, calcium perchlorate, magnesium acetate, magnesium phthalate, etc. It is also possible to use two or more of these alkaline earth metal compounds in combination. Among these, magnesium compounds are preferred because they have an excellent effect of preventing reagglomeration in slurries of inert fine particles and polyester, and magnesium chloride and magnesium acetate are particularly preferred.

Examples of phosphorus compounds include phosphoric acid compounds such as phosphoric acid, phosphorous acid, and phosphonic acid; condensed polyphosphoric acid compounds such as pyrophosphoric acid and metaphosphoric acid; and alkyl esters thereof; specifically, phosphoric acid, Examples include phosphorous acid, phosphoric acid monomethyl ester, phosphoric acid methyl ester, phosphoric acid butyl ester, methylphosphonic acid, phenylphosphonic acid monomethyl ester, pyrophosphoric acid, metaphosphoric acid, hexametaphosphoric acid, etc. Two of these phosphorus compounds
Combination use of more than one species is also possible. Among these, phosphoric acid and acidic phosphoric acid esters are particularly preferred. The alkali compounds include ammonia, primary to tertiary amine compounds, and 4 One or more compounds selected from class ammonium compounds, specifically sodium hydroxide, potassium methylate, sodium ethylene glycolate, ammonia, methylamine, methylethylamine, triethylamine, dimethylpropylamine, tetraethylammonium hydroxide. etc. can be mentioned. Particularly preferred alkali compounds are ammonia, tertiary amines, and quaternary ammonium compounds.

These three types of compounds, the alkaline earth metal compound, the phosphorus compound, and the alkali compound, must coexist with the inert fine particles in the glycol slurry. If any one or two of the three types of compounds are allowed to coexist with inert fine particles, the dispersion effect in the slurry will be insufficient and the particles will re-agglomerate in the polymer. Further, these three types of compounds may be added separately or simultaneously during slurry preparation, but it is preferable to dissolve the alkaline earth metal compound in glycol and then add the phosphorus compound and the alkali compound.

A method in which the three types of compounds are mixed in advance in a suitable solvent and then added is also suitable. The molar ratio of alkaline earth metal compound/phosphorus compound is preferably 50/1 to 1/10, more preferably 20/1 to 1/3. The molar ratio of alkaline earth metal compound/alkali compound is preferably 10/1 to 1/10, more preferably 5/1 to 1.
Must be 15. The molar ratio of the alkaline earth metal compound to the phosphorus compound is within the range of 50/1 to 1/10, and the molar ratio of the alkaline earth metal compound/alkaline compound is 10/1 to 1.
If it is within the range of /10, the dispersion effect in the slurry will be very good, and the number of aggregated coarse particles in the polyester will tend to decrease.

The usage range of the alkaline earth metal compound, phosphorus compound, and alkali compound is preferably 0.0001 to 100% by weight, more preferably 0.001 to 50% by weight based on the total amount of the three types of compounds, based on the inert fine particles. The amount is preferably 4%, more preferably 0.005 to 30% by weight, and if it is more than 100% by weight, the effect of improving dispersibility reaches a plateau and the heat resistance of the polyester becomes poor, which is undesirable in terms of undesirable coloration. Further, if it is less than 0,0001% by weight, the effect of improving dispersibility is small.

The concentration of the inert fine particles in the glycol slurry is preferably 1 to 60% by weight, more preferably 5 to 20% by weight. When it is more than 60% by weight, the dispersibility of the inert fine particles in the polymer is insufficient, while when it is less than 1% by weight, it is necessary to add a large amount of slurry, which is not efficient.

As a method for finely dispersing inert fine particles in these slurries, known dispersion means such as a high-speed stirrer such as a homomixer or a homojetter, a medium disperser using a medium such as glass beads, and ultrasonic waves may be used, or these methods may be used. Combinations of methods can be used. Furthermore, after the dispersion treatment, a method of removing a small amount of undispersed aggregated particles using filtration or a super decanter is preferably used.

The inert fine particle slurry of the present invention thus obtained is added to the polyester manufacturing process.

The amount of inert fine particles added to the polyester is preferably 0.05 to 5% by weight, more preferably 0.1 to 2% by weight. Further, in addition to inert fine particles, alkaline earth metal compounds, phosphorus compounds, and alkali compounds, any catalyst, heat stabilizer, antioxidant, ultraviolet absorber, etc. may be used in the slurry.

The inert particulate slurry of the present invention can be added at any point in the polyester manufacturing process.

It is preferably added before the start of the esterification reaction or transesterification reaction and at a stage during the polymerization reaction when the intrinsic viscosity of the polymer does not exceed 7')<0.2, but from the time when the esterification reaction and transesterification reaction are almost completed. It is best to add it before the start of the condensation reaction.

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

Note that the physical property values in the examples were measured as follows. In addition, parts in the examples are parts by weight.

△, Average primary particle size The fine particle powder is enlarged at an appropriate magnification using an optical microscope or an electron microscope, photographed, and the diameter of each primary particle in a certain direction is measured from the obtained image, and the average of 1000 particles is measured. I asked for it.

B. Dispersibility in slurry A small amount of the prepared slurry was sandwiched between two cover glasses and observed under a microscope to determine that the agglomerated portions containing multiple primary particles and surrounded by an outer ring-shaped glycol interface were identified as secondary agglomerated particles. I judged it.

C. Stability of slurry The prepared slurry was allowed to stand for 24 hours. After shaking the slurry, it was placed between two cover classes and observed under a microscope to evaluate secondary agglomerated particles. In addition, the interfacial settling distance (interfacial distance) after the slurry was allowed to stand for 7 days was measured.

D. Particle dispersion in polymer A small amount of polymer was sandwiched between two cover glasses at 280°C.
After melt-pressing and quenching, the particles were observed under a microscope, and portions where a plurality of primary particles aggregated and the particle size became coarse were determined to be coarse particles.

The dispersibility of the particles was determined as follows by observing coarse particles with a size more than four times the average primary particle size present in 1#2.

Grade 1: Less than 10 coarse particles/IrlIr12 with an average primary particle diameter of more than 448 are present.

2nd grade: 11 to 30 coarse particles/rrvn2 with a size exceeding 4 times the average primary particle diameter are present.

Grade 3: 31 to 50 coarse particles with a size more than 4 times the average primary particle diameter! rIM2 exists.

Grade 4: More than 50 coarse particles/rrwn2 with an average particle diameter of more than 448 are present.

Polymers up to grade 3 can be put to practical use.

E, intrinsic viscosity 0 Measured at 25°C using chlorophenol as a solvent.

Example 1 1 part of magnesium acetate in 10,000 parts of ethylene glycol
After dissolving 00 parts, 11 parts of phosphoric acid (0.25 times the mole relative to magnesium acetate) and 100 parts of tetraethylammonium hydroxide (1°5 times the mole relative to magnesium acetate) were added to form an ethylene glycol solution (A). was prepared. After mixing 100 parts of calcium carbonate with an average particle size of 1.1μ surface-treated with 1 part of stearic acid with 70 parts of methanol, it was added to a previously prepared solution (A > 1000 parts, (
The mixture was mixed and stirred for 1 hour in a cylindrical groove device with an inner diameter of 200 m using a ethylene glycol slurry (manufactured by Co., Ltd.) to prepare an ethylene glycol slurry. The average particle size of calcium carbonate in the obtained slurry was 1.12μ. When the slurry was observed under a microscope, no aggregated particles were observed. After the obtained slurry was allowed to stand for 24 hours, it was shaken for 2 minutes and observed under a microscope. As a result, no aggregated coarse particles were observed and the result was the same as before standing. Further, no interfacial sedimentation was observed even when the slurry was allowed to stand for 7 days.

140~
The transesterification reaction was carried out at 240°C. Next, 0.03 part of antimony trioxide and 5 parts of the prepared ethylene glycol slurry of calcium carbonate were added, and the mixture was heated to 250-29
A polymerization reaction was carried out at 0° C. under high vacuum, and after 120 minutes, a polymer having an intrinsic viscosity of 0.65 was obtained.

When the dispersion state of particles in the polymer was observed, the number of aggregated coarse particles was 1/#2, indicating a good dispersion state. Next, this polymer was melt-extruded at 290°C, stretched 3.5 times in the machine direction at 90°C and 3.5 times in the transverse direction at 130°C, and then heat-treated at 220°C to create a film with a thickness of 15μ. did. This film is ASTM-D-1894-63TK
The coefficient of dynamic friction of the film measured by Q was 0.5, and the maximum surface roughness was 0.03μ.

Comparative Example 1 A calcium carbonate slurry was prepared in exactly the same manner as in Example 1 except that ethylene glycol was used instead of the ethylene glycol solution (A). Microscopic observation of the 1q slurry revealed that there were more than 100 aggregated particles, and the interfacial sedimentation after the slurry was left for 7 days was 7C)s.
Met. In addition, a polymer was prepared using this slurry in the same manner as in Example 1, and when the dispersion state in the polymer was observed under a microscope, the number of aggregated particles was as large as 100 or more, similar to the slurry. When it was prepared and the maximum surface roughness was measured, it was found that the number of coarse protrusions had increased to 0.2μ.

Examples 2 to 11 and Comparative Examples 2 to 7 In Example 1, the ethylene glycol solution (A) was
Ethylene glycol slurry of various inert particles was prepared using 1000 parts of ethylene glycol solution prepared in advance as shown in Table 1 instead of 0.00 parts, and the slurry was added in the same manner as in Example 1 to create a polymer. . The dispersion state of the particles in the obtained slurry and polymer were both good as shown in Table 1.

On the other hand, a method other than the present invention, that is, a total alkaline earth compound, a phosphorus compound, and an alkali compound are used alone or in combination.
As shown in Comparative Examples 2 to 7 in Table 1, the dispersion state of the particles in the slurry and polymer was poor in those used only by the inventor.

(The following is a blank space) [Effects of the Invention] As described above, the present invention provides inert organic fine particles and/or inert inorganic fine particles that have been surface-treated using an organic compound, and an alkaline earth metal compound, a phosphorus compound, and an alkali metal compound. This is a polyester manufacturing method characterized by adding a finely dispersed glycol slurry with a compound to the polyester manufacturing process, and by applying the method of the present invention, the following effects are exhibited. .

(1) Re-agglomeration of inert fine particles in the dispersed slurry can be prevented, and the stability of the slurry is improved.

(2) The dispersibility of inert fine particles having good affinity with polyester in polyester is improved, and a polymer having an extremely small amount of aggregated coarse particles can be obtained.

(3) When added to polyester, the polyester is less colored and a polyester with good color tone can be obtained.

The polyester obtained by the method of the present invention has excellent affinity between particles and polymer, and is a polymer with excellent dispersibility of particles, so when molded into fibers, films, molded products, etc., it has the following effects. Demonstrated.

<1)'% yarn, there is less yarn breakage during spinning, and there is less process contamination due to wear or falling off of the spinnerets and guides.

(2) There is less clogging of the polymer filter during the yarn spinning and membrane forming processes, and an increase in filtration pressure can be suppressed.

(3) When made into a film, there are fewer coarse protrusions, and the generation of white powder due to falling off, etc., can be prevented, and contamination during the manufacturing process can be reduced.

(4) There are fewer coarse protrusions due to aggregated coarse particles, and the fine unevenness and uniformity of the thread and film surfaces are improved.

Claims (3)

[Claims] (1) When producing polyester from a dicarboxylic acid component and glycol, alkaline earth metal compounds, phosphorus compounds, and alkali compounds are added to inert organic particles and/or inert inorganic particles that have been surface-treated with organic compounds. 1. A method for producing polyester, which comprises adding to a polyester production process a glycol slurry containing finely dispersed glycol slurry. (2) The method for producing a polyester according to claim (1), wherein the organic compound is an aliphatic carboxylic acid, an alkali metal salt thereof, or an alkaline earth metal salt thereof. (3) The method for producing polyester according to claim (1) or (2), wherein the inert inorganic fine particles are calcium carbonate.