JPH0481618B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to a method for producing polyester having improved runnability, abrasion resistance, and surface properties and is suitable for polyester fibers, polyester films, or other polyester molded products. [Prior art and its problems] Polyester in general, and polyethylene terephthalate in particular, has excellent mechanical properties, heat resistance, weather resistance, electrical insulation, and chemical resistance, so it is used not only as textiles for clothing and industrial purposes, but also as films for magnetic tapes and photographs. It is widely used in film fields such as industrial films, electric insulation films, and capacitor films. When polyester is used in the film field, it is important to ensure that it passes through the forming processes of melt extrusion, stretching, and heat treatment, or for film forming, winding, cutting, surface coating of magnetic layers, etc., and incorporation into electrical components. Considering the value of the final product in terms of properties, slipperiness of film products, abrasion resistance, and surface properties, we manufacture a polyester composition containing fine particles, which imparts surface smoothness by imparting appropriate roughness to the surface. It is common practice to facilitate film flow during film formation and to improve surface properties and abrasion resistance. Polyester compositions containing such fine particles include inert materials such as silicon oxide, titanium dioxide, calcium carbonate, talc, clay, organic polymers, etc.
Polyester compositions obtained by adding and blending insoluble fine particles, metal compounds such as alkalis and alkaline earths added to the polyester synthesis system, and fine particles containing phosphorus compounds as part of their constituent components are subjected to a polycondensation reaction process. Polyester compositions obtained by precipitation in a polyester are known. However, such known fine particle-containing polyester compositions have the following problems, and especially when formed into a film, it is difficult to obtain satisfactory properties such as ease of sliding, abrasion resistance, surface condition, and film formability. I couldn't help it. That is, in the polyester composition obtained by the above-mentioned method of adding insoluble fine particles, it is difficult to make the added particles fine, coarse particles are mixed together due to agglomeration of particles, and the particle size is non-uniform. Since these particles have relatively low compatibility with the polyester base material, when formed into a film or the like, they may come off from the film and cause other problems. In addition, coarse protrusions caused by coarse particles coexist, causing problems such as sticky eyes and dropouts, and furthermore, dispersants added to prevent particles from agglomerating often reduce the heat resistance and electrical properties of these polyesters. This results in disadvantages such as: Therefore, in JP-A-53-125495, in order to finely disperse the particles, a special stirring blade is used.
Although an example in which additive particles are finely dispersed and present in polyester has been disclosed, the purpose has not been fully achieved. On the other hand, in polyester compositions containing particles obtained by the so-called fine particle precipitation method described above, it is difficult to control the particle size of the precipitated particles when the particle content is increased, and furthermore, in order to increase the particle amount, it is difficult to control the particle size of the precipitated particles. If the amount added is increased, problems such as an increase in coarse particles due to agglomeration of particles will occur. For example, JP-A-53-4103 discloses an example of precipitated particles containing lithium element, but it has not yet shown sufficient effects in the above-mentioned applications. Particularly in recent years, the use of polyester in magnetic tape applications has increased significantly, and polyesters have come to be used in many applications such as audio tapes, video tapes, and memory tapes, and the required properties are becoming increasingly sophisticated. Furthermore, in order to achieve smaller size and higher density, it is necessary to reduce the thickness of the magnetic tape, and there is an increasing demand for making the irregularities on the film surface more uniform and fine. Furthermore, coarse particles are blended with polyester that does not contain particles or has a small particle content to obtain a polyester film, and in order to give the polyester film good surface properties and to make a molded product with excellent slipperiness. There is a need for a raw material that is free of grains and contains a large amount of fine particles. However, the finer these particles are and the larger the amount of particles, the more likely coarse particles will be produced due to aggregation of particles. [Object of the Invention] In view of the above-mentioned circumstances, the object of the present invention is to provide a film containing a large amount of uniform fine particles and formed into a film.
The object of the present invention is to obtain a polyester that is effective in improving the abrasion resistance and slipperiness of films. [Structure of the Invention] The object of the present invention described above is to perform a transesterification or esterification reaction between terephthalic acid or its ester-forming derivative and a glycol, and then to perform a polycondensation reaction to produce a polyester. Particles formed by the reaction of terephthalic acid or terephthalic acid derivatives with alkali metal compounds and/or alkaline earth metal compounds and particulate matter insoluble in the system at any time before the start of the polyester synthesis reaction system. This can be achieved by a method for producing polyester characterized by adding the following. The polyester in the present invention is mainly composed of polyethylene terephthalate that can be molded into fibers, films, and other molded products, and may be a homopolyester or a copolyester, and the components to be copolymerized include: For example, diethylene glycol, propylene glycol, neopentyl glycol, polyalkylene glycol, p
- Diol components such as xylin glycol, 1,4-cyclohexanedimethanol, 5-sodium sulforesorcin, adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 5-sodium sulfoisophthalic acid, etc. Polyfunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid, oxycarboxylic acid components such as p-oxyethoxybenzoic acid, and the like. When the dicarboxylic acid component is a dicarboxylic acid, after the esterification reaction with glycol, or when it is a dicarboxylic acid ester, after the transesterification reaction with glycol, the obtained prepolymer is subjected to a polycondensation reaction at high temperature and reduced pressure to obtain a polyester. . Terephthalic acid and terephthalic acid derivatives used in the present invention to obtain particles produced by the reaction of terephthalic acid or terephthalic acid derivatives with alkali metals and/or alkaline earth metal compounds outside the polyester synthesis reaction system are terephthalic acid and terephthalic acid derivatives. having a skeleton, such as terephthalic acid

[Formula] Bis-(B-hydroxyethyl) terephthalate dimethyl terephthalate

[Formula] Bis(hydroxybutyl) terephthalate Monohydroxyethyl terephthalate Monomethyl terephthalate

〔Effect of the invention〕

The polyester of the present invention is characterized in that it contains a large amount of uniform, fine particles, and has an extremely small amount of coarse particles compared to polyester obtained by conventional precipitate particle generation methods or addition methods. Furthermore, it has good compatibility with polyester, and when producing fibers or films from the polyester, the following effects, which could not be achieved with conventional products, are exhibited. During the melt-molding process into fibers and films, fibers and films with less clogging of filters and good workability in post-processing steps can be obtained. Even when formed into an extremely thin film with a thickness of 3μ or less, it contains many uniform fine particles, so there is no blocking phenomenon between films, between films and metals, and between films and felts, making it extremely easy to slip. It is possible to obtain a polyester film which has excellent properties, has good surface properties, has less particle shedding, and has excellent abrasion resistance. In addition, since it contains a large amount of uniform fine particles, it can be used diluted, and in this case, there is no film stickiness, and it is especially useful for magnetic tape applications because there are no dropouts, uneven images, or skipping during playback. It is. The polyester obtained by the method of the present invention can be preferably used not only for multifilament, stable fibers, non-oriented, uniaxially oriented, biaxially oriented films, but also for monofilaments and plastics. The present invention will be explained in more detail below using examples. The characteristic values of the obtained polyester were measured according to the following method. (A) Particle size rank in polymer 20 mg of polymer was sandwiched between two cover glasses.
The particles were melt-pressed at 280°C, cooled, and then observed under a microscope, and ranked based on the average particle size as follows. A: Particle size <1.0μ B: Particle size ≧1.0μ, <3.0μ C: Particle size ≧3.0μ, <5.0μ D: Particle size ≧5.0μ (B) Particle dispersibility in polymer Two sheets of 20 mg of polymer scissors between the coverslips of
Melt press at 280℃, observe with microscope after cooling, 1
The following judgment is made based on the number of coarse particles of 3μ or more present in ^mm2 . Grade 1: Coarse particles exceeding 3 μ are present in less than 10 pieces/mm ² . 2nd grade: 10 to 30 coarse particles/mm ² with a size exceeding 3 μ are present. Grade 3: Coarse particles exceeding 3 μ are present in an amount exceeding 30 pieces/mm ² . (C) Intrinsic viscosity of polymer This is a value measured at 25°C using O-chlorophenol as a solvent. (D) Film properties (a) Film friction coefficient Using a slip tester, ASTM-D-
Measured according to method 1894B. The coefficient of static friction was used as a measure of the slipperiness of the film. (b) Roughness of film surface irregularities The film surface was observed using a stylus type roughness meter, and the difference between the highest and lowest parts of the surface irregularities obtained was expressed in μ units. Example 1 (Production of particles) 5.4 parts by weight of calcium acetate hydrate, 11.7 parts by weight of bis-(β-hydroxyethyl) terephthalate, and 82.9 parts by weight of ethylene glycol were charged into a container equipped with a stirring device and a reflux tube, and stirred. The reaction was carried out at 190°C for 3 hours. The resulting particle generation slurry was stirred at a rotation speed of 3000 r.pm using a high-speed stirrer.
The mixture was stirred at high speed for 2 hours to finely disperse the particles and obtain a particle slurry. (Production method of polyester) A transesterification reaction is carried out by a conventional method using 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, and 0.04 parts by weight of manganese acetate tetrahydrate as a catalyst, and the product is mixed with 0.03 parts by weight of antimony trioxide and phosphorus. 0.02 parts by weight of trimethyl acid, 0.3 parts by weight of the ethylene glycol slurry of the particles produced above, and 0.2 parts by weight of well-finely dispersed silicon dioxide (specific surface area 200 m ² /g) in advance as an ethylene glycol slurry with a concentration of 10% by weight. and polymerize using conventional methods to obtain the intrinsic viscosity.
A polymer of 0.614 was obtained. The viscosity in the polymer was A rank, and the dispersibility was 1st grade, which was good. Example 2 (Manufacture of particles) In a container with an internal volume of 30 mm equipped with a stirring device,
100 parts by weight of (β-hydroxyethyl) terephthalate and 250 parts by weight of ethylene glycol were added and dissolved by heating. Then add calcium acetate-hydrate with stirring.
35 parts by weight and 40 parts by weight of lithium acetate dihydrate were added, and the mixture was reacted at 190°C for 3 hours. Next, 200 parts by weight of ethylene glycol, 30 parts by weight of trimethyl phosphate,
10 parts by weight of phosphorous acid was added and reacted at 180°C for 1 hour. The obtained particle generation slurry was stirred at high speed for 2 hours at a rotation speed of 3000 rpm using a high speed stirrer to finely disperse the particles and obtain a particle slurry. (Production method of polyester) A transesterification reaction is carried out by a conventional method using 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, and 0.04 parts by weight of manganese acetate tetrahydrate as a catalyst, and the product is mixed with 0.03 parts by weight of antimony trioxide and phosphorus. 0.02 parts by weight of trimethyl acid, 0.3 parts by weight of the ethylene glycol slurry of the particles produced above, and 10% by weight in advance.
Well-dispersed silicon dioxide as a concentrated ethylene glycol slurry (specific surface area 200 m ² /g)
0.2 parts by weight was added and polymerized by a conventional method to obtain a polymer having an intrinsic viscosity of 0.627. The viscosity in the polymer was A rank, and the dispersibility was 1st grade, which was extremely good. Comparative Example 1 In Example 2, after the transesterification reaction,
A product with an intrinsic viscosity of 0.609 was prepared in the same manner as in Example 2, except that the particles produced in Example 2 were not added, and only 0.3 parts by weight of lithium acetate, 0.2 parts by weight of trimethyl phosphate, and 0.03 parts by weight of antimony trioxide were added. I got a polymer. The viscosity in the polymer was C rank, and the dispersibility was tertiary, which was not preferable. Examples 3 to 8 Polyesters were obtained in the same manner as in Example 2, except that the type and amount of inert material particles were changed. Particle size and dispersibility in the polymer are shown in Table 1. Example 9 The polyester composition obtained in Example 1 was formed into a sheet at 290°C by a conventional method, and stretched with a biaxial stretching machine at a longitudinal stretch ratio of 3.3 times and a transverse stretch ratio of 3.4 times.
A film with a thickness of 12μ was obtained by heat treatment at ℃. Work stability during coating was good, and there were no problems such as membrane tearing. Friction coefficient of the obtained film
0.68, the average roughness of the film surface was 0.021μ, and the maximum roughness of the film surface was 0.22μ, which were good. Example 10 A film with a thickness of 12 μm was obtained in the same manner as in Example 9 except that the polyester obtained in Example 2 was used.
The friction coefficient of the obtained film was 0.64, the average roughness of the film surface was 0.023μ, and the maximum roughness of the film surface was 0.24μ.
It was good. Comparative Example 2 A film with a thickness of 12 μm was obtained in the same manner as in Example 9 except that the polyester obtained in Comparative Example 1 was used. The friction coefficient of the obtained film was 0.56, the average roughness of the film surface was 0.038μ, and the maximum roughness of the film surface was
It was 0.39μ, which was not preferable. Example 11 In Example 2, after the transesterification reaction,
Into the product, 0.03 parts by weight of antimony trioxide, 0.02 parts by weight of trimethyl phosphate, and 0.6 parts by weight of the ethylene glycol slurry of the particles produced in Example 2 are finely dispersed in advance as ethylene glycol slurry with a concentration of 10% by weight. 0.6 parts by weight of silicon dioxide (specific surface area 200 m ² /g) was added, and the mixture was polymerized by a conventional method to obtain the intrinsic viscosity.
A polymer of 0.605 was obtained. The viscosity in the polymer was A rank, and the dispersibility was 1st grade, which was good. Example 12 The esterification reaction product was charged into an esterification reaction vessel equipped with a stirring device, a partial condenser, and a raw material inlet,
Melting was carried out by heating at 250°C in the presence of _N2 . An ethylene glycol slurry of terephthalic acid with a molar ratio of ethylene glycol to terephthalic acid adjusted to 1.20 was continuously supplied to the reaction vessel, water was distilled off, and an esterification reaction was carried out. the esterification product
105 parts by weight (ethylene terephthalate unit 100
(equivalent to parts by weight) into a polycondensation reactor and heated to 250°C.
0.2 parts by weight of the particle slurry obtained in Example 2 as particles, 0.03 parts by weight of antimony trioxide,
In advance, 0.1 part by weight of well-dispersed silicon dioxide (specific surface area 200 m ² /g) was added as an ethylene glycol slurry with a concentration of 10% by weight, and the pressure in the system was gradually reduced to cause a polycondensation reaction, resulting in an intrinsic viscosity of 0.616.
obtained a polymer. The viscosity in the polymer was A rank, and the dispersibility was 1st grade, which was good.

【table】

Claims (1)

[Claims] 1. When producing a polyester by transesterifying or esterifying terephthalic acid or its ester-forming derivative with a glycol and subsequently carrying out a polycondensation reaction, the synthesis reaction of the polyester may be carried out at any time before the start of the polycondensation reaction. Production of polyester characterized by adding particles produced by the reaction of terephthalic acid or a terephthalic acid derivative with an alkali metal compound and/or alkaline earth metal compound outside the system and particulate matter insoluble in the system. Method.