JPS6198730A - Production of polyester - Google Patents

Abstract

PURPOSE:To obtain the titled polymer containing a large amount of uniform fine particles and capable of giving a film having improved abrasion resistance, etc., by adding a specific particle to the polyester synthetic reaction system prior to the initiation of the polycondensation reaction, and adding an alkali metal compound during the polycondensation reaction. CONSTITUTION:Terephthalic acid (derivative) is made to react with an alkali metal or alkaline earth metal compound (preferably hydroxide, etc.) outside of the synthetic reaction system of polyester to produce particles. Terephthalic acid (or its ester-forming derivative) and a glycol are subjected to ester-exchange reaction, and at the same time, the particles produced by the above process are added to the polyester synthetic reaction system at an arbitrary stage prior to the initiation of the polycondensation -reac-tion. Thereafter, an alkali metal or alkaline earth metal compound (preferably lithium hydroxide, etc.) is added to the system during the polycondensation reaction to obtain the objective polymer containing precipitated particles containing an alkali metal or alkaline earth metal as a part of the constituent component.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for producing polyester having improved running properties, abrasion resistance, and surface properties suitable for polyester fibers, polyester films, or polyester molded articles.

[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 as a fiber for clothing and industrial use, as well as for magnetic tape films, photographic films, ashes, and condensers. It is widely used in the film field such as 7-film.

When polyester is used in the film field, it needs to pass through the forming processes of melt extrusion, stretching, and heat treatment, or when forming a film, it needs to be rolled up, cut, surface coated with magnetic layers, etc., and incorporated into electrical parts. Final products such as flexibility, slippage of film products, abrasion resistance, and surface properties.
In order to impart these required properties, a polyester composition containing fine particles is produced, which gives the surface appropriate roughness to impart smoothness to the surface, facilitate film flow during film formation, and improve the surface properties. , it is common practice to improve wear resistance.

Polyester compositions containing such fine particles include: (1) silicon oxide, titanium dioxide, and calcium carbonate.

Polyester compositions obtained by adding and blending inert, insoluble fine particles such as talc, clay, and organic polymers, ■ Adding metal compounds such as alkalis and alkaline earths, and phosphorus compounds to synthetic polyester threads. Polyester compositions obtained by precipitating fine particles during a polycondensation reaction step are known.

However, such known fine particle-containing polyester compositions have the following problems, and especially when formed into a film, their slipperiness, abrasion resistance, surface condition, film formability, etc. are not satisfactory. There wasn't.

In other words, in the polyester composition obtained by the method of adding insoluble fine particles described in FRI I. However, 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 fine eyes and dropouts.Furthermore, dispersants added to prevent particle agglomeration often affect the heat resistance and electrical properties of these polyesters. This results in disadvantages such as deterioration of characteristics. Therefore, in order to finely disperse the particles, JP-A-53-125495 discloses an example in which the added particles are finely dispersed and present in the polyester using a special stirring blade, but this does not sufficiently achieve the purpose. This has not yet been achieved.

On the other hand, in polyester compositions containing particles obtained by the so-called fine particle precipitation method mentioned above, it is difficult to control the particle size of the precipitated particles when the particle content is increased.
Furthermore, if the amount of the catalytic metal compound added is increased in order to increase the amount of particles, problems such as an increase in coarse particles due to aggregation of particles occur. For example, Japanese Patent Application Laid-Open No. 53-4103 discloses an example of precipitated particles containing a beam element, but it has not yet shown sufficient effects in the above-mentioned applications.

Particularly in recent years, the use of polyester has grown significantly, and it has come to be used in many applications such as audio, video tape, and memory tape, and the required properties are becoming increasingly sophisticated.

Furthermore, in order to achieve miniaturization and high density, it is necessary to reduce the thickness f of the magnetic tape, and there is an increasing demand for smoothing the irregularities on the film surface into more uniform and finer details.

Furthermore, polyester film 'fx' can be produced by blending it with polyester that does not contain particles or has a small particle content.
In order to impart good surface properties to m1,3 polyester films and to make molded products with excellent slipperiness, raw materials are required that are free of coarse particles and contain a large amount of fine particles. However, the finer these particles are and the more the particle wind is, the more coarse particles are likely to be formed due to aggregation of the particles.

[Purpose of the invention]

In view of the above-mentioned circumstances, an object of the present invention is to obtain a method for producing polyester that contains a large amount of uniform fine particles and is effective in improving the abrasion resistance and slipperiness of the film when formed into a film.

[Structure of the invention]

The purpose of the present invention described above is to carry out a transesterification or esterification reaction between terephthalic acid or its ester-forming derivative and a glycol, and then to carry out a polycondensation reaction to produce a polyester. At this point, outside the polyester synthesis reaction system, terephthalic acid or a terephthalic acid derivative and an alkali metal compound and/or an alkaline earth metal compound are added to form an alkali metal and/or an alkaline earth metal. This can be achieved by a polyester manufacturing method characterized by precipitating particles having the above components as part of the components.

Uninvented polyester is mainly composed of polyethylene terephthalate that can be molded into fibers, films, and other molded products, and even if it is a homopolyester,
It may be a copolyester, and examples of the components to be copolymerized include hashethylene glycol, furopylene gelicol, neopentyl glycol, polyalkylene glycol, p-xylylene glycol, 1,4-cyclohexane dimetatool, Diol components such as 5-sodium sulforesorcin, dicarboxylic acid components such as adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 5-sodium sulfoisophthalic acid, trimellitic acid, pyromellitic acid, etc. Examples include polyfunctional dicarboxylic acid components, oxydicarboxylic acid components such as p-oxyethoxybenzoic acid, etc.

When the dicarboxylic acid component is a dicarboxylic acid, after the esterification reaction with glycol, and when the dicarboxylic acid ester is 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 a terephthalic acid derivative with an alkali metal compound and/or an alkaline earth metal compound outside the polyester synthesis reaction system. has a terephthaloyl skeleton, such as terephthalic acid (HOOC phthalate (HOCH2CH20CO◎C00CH2CH2
0H)% dimethyl terephthalate) (OR50CiO◎c
oocH,) s Bis(hydroxybutyl) terephthalate (HO-CH2CH2CH2CH20CO◎C00
CH2CH2CH2CH2QH), monohydroxyethyl terephthalate (HocH2CH2-oco◎C0O
H), monomethyl terephthalate (C-H3000■C
0OH), monohydroxybutyl terephthalate) (
HOCH20H20H2CH20GO@C0OH) and polyethylene terephthalate low polymer [LIofa
n2-CH20CO◎coo %CIIz CH20H
(n-1 to 6)) and mixtures thereof. In particular, ester-forming derivatives that are the same as the desired polyester are preferred because they do not reduce the quality of the polymer.

In addition, alkali gold k used for particle generation outside the reaction system
Jss alkaline earth total bending compounds include alkali gold (・JSb alkaline earth metal group 0 hydride, alcolade, chloride, hydroxide, carbonate, carboxylate, sulfate,
Examples include nitrates.

Specific examples include lithium acetate, lithium chloride, sodium acetate, lithium hydroxide, sodium hydroxide, calcium acetate, magnesium acetate, manganese acetate, calcium chloride, magnesium chloride, lithium carbonate, and the like. Among these compounds, hydroxides and aliphatic dicarboxylic acid salts are preferably used because they suppress side reactions and are easy to post-process.

Furthermore, in producing particles outside the reaction system, a phosphorus compound may be used in addition to terephthalic acid or a terephthalic acid derivative, an alkali metal compound and/or an alkaline earth metal compound. The phosphorus compounds used in this case include phosphoric acid, phosphorous acid, or their methyl esters, ethyl esters, phenyl esters, half-esters thereof, phosphonic acids, phosphinic acids, or esters thereof. More than one kind of punch.

The particles produced outside the reaction system used for producing the polyester of the present invention are obtained by mixing terephthalic acid or a terephthalic acid derivative with an alkali metal compound and/or an alkaline earth metal compound in a medium such as ethylene glycol.
It is obtained by reacting at a temperature of 00°C to 200°C. Furthermore, when using a phosphorus compound, terephthalic acid or a terephthalic acid derivative, an alkali metal and/or alkaline earth metal compound, and a phosphorus compound are similarly mixed in a medium such as ethylene glycol.
It is obtained by reacting at a temperature of 00°C to 200°C.

Furthermore, an example of a method suitable for producing particles produced outside the reaction system used for producing the polyester of the present invention will be described.

That is, a terephthalic acid derivative is heated and dissolved in ethylene glyfur in an amount of 20 times or more mole or more per terephthaloyl unit of terephthalic acid or a terephthalic acid derivative, and 1 to 100% is dissolved under stirring.
This is a method in which 4 times the mole of an alkali metal compound and/or an alkaline earth metal compound is added and the reaction is carried out at a temperature of 100 to 200°C, preferably 150 to 190°C, for 60 to 240 minutes.

In addition, when using a phosphorus compound, after the above reaction, 1 to 4 times the mole of the phosphorus compound is added to the terephthaloyl unit of terephthalic acid or its derivative.
30-120°C, preferably at a temperature of 150-180°C
Obtained by a method of reacting for minutes. In this case, the order of addition of the alkali metal compound and/or alkaline earth metal compound and the phosphorus compound may be reversed to the above-described order of addition, or in some cases, they may be added simultaneously.

The particles obtained in this way can be used after separating the particles by a method such as filtration or centrifugation, but the reaction solution obtained can also be used as is, or after dilution or concentration. .

In addition, the amount of particles obtained outside the polyester reaction system used is 0.005 to
2.0 weight ff1% is preferable, more preferably 0.01
-1.0% by weight.

The timing of adding the particles to the reaction system is preferably after the transesterification reaction or esterification reaction is substantially completed and before the start of the polycondensation reaction, but is not limited to dirt, and can be added at any time before the start of the polycondensation reaction. Can be added.

In the method of the present invention, all precipitated particles are generated in the polycondensation reaction system in the presence of particles synthesized outside the polycondensation reaction system. Therefore, a large amount of uniform and fine precipitated particles, which could not be obtained by the precipitated particle method in the conventional polyester synthesis process, can be produced.

The alkali metal compounds and alkaline earth metal compounds for producing precipitated particles in the reaction system used in the present invention include hydrides, alcoholades, chlorides, hydroxides, carbonates, and carboxylates of alkali metals and alkaline earth metals. Examples include acid salts and sulfates.

Specific examples include lithium acetate, lithium chloride, lithium hydroxide, sodium acetate, calcium acetate, magnesium chloride, etc., and not only one type but also two or more types can be used in combination. Among them, calcium and lithium hydroxides and aliphatic carboxylic acid salts are preferably used because they produce precipitated particles in many forms, suppress side reactions, and are easy to post-process. The amount of these metal compounds to be used is preferably 0.01 to 3% by weight, more preferably 0.01 to 2.0% by weight, based on the total acid component constituting the polyester, and is optionally used before the start of the polycondensation reaction. It is particularly preferably added after the transesterification reaction or esterification reaction is substantially completed and before the start of the single polycondensation reaction.

A compound can also be used. The phosphorus compounds to be removed include phosphoric acid, phosphorous acid, or their methyl esters, ethyl esters, phenyl esters, and for Sara, phosphonic acids, phosphinic acids, or their esters. One or more types selected from the group can be mentioned. The amount of the phosphorus compound used is also related to the amount of the metal compound used, but it is preferably 0.001 to 2 times the total acid component constituting the polyester.
L: Preferably 0.01 to 2% by weight. The timing of addition is preferably after the completion of the esterification or transesterification reaction, and is preferably added at any time before the start of the single polycondensation reaction.

In the present invention, the esterification reaction or the transesterification reaction includes appropriate amounts of catalysts such as alkali metals such as lithium, sodium, and potassium, alkaline earth metals such as magnesium/umium, calcium, strontium, and barium, and hydrides of zinc and manganese. Alcoholades, chlorides and glycol-soluble salts of monocarboxylic acids are preferably used as catalysts. Particularly preferred are lithium acetate, lynnium acetate, strontium acetate, zinc acetate, manganese acetate, and manganese chloride.

Typical catalysts used for the polycondensation of bishydroxyalkyl esters of aromatic dicarboxylic acids are glycol-soluble antimony or germanium compounds, such as antimony trioxide, antimony potassium tartrate,
Antimony oxychloride, germanium oxide, and the like are preferably used.

〔Effect of the invention〕

The polyester of the present invention has uniform, fine precipitated particles with a large number of particles.
In addition, it has the characteristic that it contains extremely few coarse particles compared to polyesters 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 process of melt-molding fibers and films, 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 locking 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 such as excellent hardness, good surface properties, less particle shedding, and 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 fins, and especially when used for magnetic tape, there are no dropouts, uneven images, or skipping during playback. , extremely useful.

The polyester obtained by Kikomei's fuj method can be preferably used not only for multifilaments, staple fibers, non-oriented, -axially oriented, and biaxially oriented films, but also for monofilaments and plastics.

The present invention will be explained in more detail below with reference to Examples.
The present invention is not limited to the following examples.

The characteristic values of the obtained polyester were measured according to the following method.

(A) Particle size rank in polymer 20 m7 of polymer was sandwiched between two cover glasses, 28
The particles were melt-pressed at 0°C, observed under a 6M microscope after cooling, and ranked based on the average particle diameter as follows.

A: Particle size <1.0μ B: Particle size ≧1.0μ, <6.0μ C: Particle size ≧5.0μ, <50μ m] Particle size ≧5.0μ (B) Particle dispersibility in polymer Sandwich Polymer 20WII between two cover glasses,
After cooling with a melt press at 80°C, it was observed under a microscope, and the following judgment was made based on the number of coarse particles of 3 μ or more present in 1-.

There are less than 10/- coarse particles with a particle size exceeding 3μ (1st grade).

Secondary: 10 to 30/- coarse particles exceeding 3μ are present.

There are more than 30 coarse particles/ml of tertiary grade = more than 3μ.

(c) Intrinsic viscosity of polymer This is a value measured at 25°C using 0-chlorophenol as a solvent.

(D) Film Properties (a) Film Friction Coefficient Measured using a slip tester according to ASTM-D-1894I3 method. 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) A stirring device and a container equipped with a reflux tube (e) contained 5.4 parts by weight of calcium acetate aquarium, 11.7 parts by weight of bis-(β-hydroxyethyl) terephthalate, and 82.9 parts by weight of ethylene glycol. 6 parts by weight at 190℃ with stirring.
Time reacted. The obtained particle generation slurry was stirred at high speed for 2 hours at a rotation speed of 5000 r, P, m using a high speed stirrer to finely disperse the particles and obtain a particle slurry.

(Method for producing 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 0.09 parts by weight of calcium acetate, and the product is mixed with 0.03 parts by weight of antimony trioxide. 1 part, 0.2 parts by weight of the ethylene glycol slurry of the particles produced above, 0.3 parts by weight of lithium acetate, and 0.2 parts by weight of trimethyl phosphate were polymerized by a conventional method to obtain an intrinsic viscosity. A polymer of 0.651 was obtained.

The particle size in the polymer was A lac, and the dispersibility in the grain was first grade, which was extremely good.

Comparative Example 1 In Example 1, after completion of the transesterification reaction, 0.3 parts by weight of lithium acetate, 02 parts by weight of trimethyl phosphate, and 0.03 parts by weight of antimony trioxide were added without adding the above-produced elementary particles.
A polymer having an intrinsic viscosity of 0.609 was obtained in the same manner as in Example 1, except that only parts by weight were added and reacted. The particle size in the polymer was rank C, and the dispersibility was rank 6, which was not desirable.

Example 2 (Manufacture of particles) A container with an internal volume of 30 J equipped with a stirring device was prepared using Vinu (β).
100 parts by weight of -hydroquinethyl) terephthalate and 250 parts of ethylene glycol were added and dissolved by heating. Then, while stirring, 35 parts by weight of calcium acetate hydrate 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, and 10 parts by weight of phosphorous acid were added, and the mixture was reacted at 180° C. for 1 hour. The obtained particle generation slurry was stirred at a rotation speed of 300 Or, P, m 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.

(Method for producing polyester) After the transesterification reaction in Example 1, instead of the particle slurry used in Example 1, 0.2 parts by weight of ethylene glycol slurry 'J-f of the particles produced above was added. was subjected to a polycondensation reaction in the same manner as in Example 1,
A polymer with an intrinsic viscosity of 0.631 was obtained. The viscosity in the polymer was A rank, and the dispersibility was 1st grade, which was extremely good.

Example 3 A reaction was carried out in the same manner as in Example 1 using Q-calcium hydroxide instead of calcium acetate monohydrate, and subsequent treatments were carried out in the same manner to obtain a particle slurry. The reaction was carried out in the same manner as in Example 1, except that 0.2 parts by weight of the ethylene glycol slurry of the particles was added, and the intrinsic viscosity was 0.1 s.
26 polymers were obtained. The particle size in the polymer was A rank, and the dispersibility was 1st grade, which was good.

Example 4 The polyester obtained in Example 1 was formed into a sheet at 290°C by a conventional method, stretched with a biaxial stretching machine at a longitudinal stretch ratio of 3.3 times and a transverse stretch ratio of 6.4 times, and then heat-treated at 215°C. A film with a thickness of 12 μm was obtained. Work stability during film formation was good, and there were no problems such as film breakage.

The friction coefficient of the obtained film was 0.78, the average roughness of the film surface was 0.021μ, and the maximum roughness of the film surface was 0.2.
It was 2μ, which was good.

Example 5 The polyester obtained in Example 2 was sorted at 290°C by a conventional method, stretched at a biaxial stretching machine (longitudinal stretch ratio of 6.3 times, transverse stretch ratio of 3° to 4 times), and then heat treated at 215°C. A film with a thickness of 12 μm was obtained.The work stability during film formation was good, and there were no problems such as film tearing.The obtained film had a coefficient of friction of 0.76 and an average roughness of the film surface of 0.
．． 024μ, and the maximum film surface roughness was 0.25μ, which was good.

Comparative Example 2 A film with a thickness of 12 μm was obtained in the same manner as in Example 4, except that the polyester obtained in Comparative Example 1 was used. The obtained film had a friction coefficient of 0.56, an average film surface roughness of 0.038 μm, and a maximum film surface roughness of 0.39 μm, which were not preferable in terms of coarse protrusions.

Example 6 After completing the transesterification reaction in Example 1, 0.1 part by weight of the particles obtained in Example 1, 0.06 part by weight of lithium acetate,
A polymer having an intrinsic viscosity of 0.617 was obtained in the same manner as in Example 1 except that 0.05 parts by weight of phosphorous acid was added and the reaction was carried out. The particle size rank in the polymer was A1, and the particle dispersibility was 1st grade, which was extremely preferable.

Example 7 A transesterification reaction was carried out in a conventional manner from 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol using 0.035 parts by weight of manganese acetate as a catalyst, and the resulting product was mixed with 0.03 parts by weight of antimony dioxide, 0.025 parts by weight of trimethyl phosphate was added and polymerized by a conventional method to obtain a polymer having an intrinsic viscosity of 0.620. After mixing 75 parts by weight of the polymer and 25 parts by weight of the polymer obtained in Example 2, a film having a thickness of 12 μm was obtained in the same manner as in Example 4. Film friction coefficient 0.96, film surface average roughness 0.014μ, film surface maximum roughness 0
．． It was 15μ, which was good.

Example 8 Example 2t After completion of the transesterification reaction.

0.05 parts by weight of particles obtained in Example 2, 0.05 parts by weight of lithium acetate.
A polymer having an intrinsic viscosity of 0.628 was obtained in the same manner as in Example 2 except that 0.06 parts by weight and 0.03 parts by weight of phosphorous acid were added and reacted. Particle size rank in polymer is A, particle dispersibility is 1
grade, and was extremely preferable.

Example 9 Stirring device, partial condenser, and raw material inlet. Esterification reaction vessel set up? Then, charge the esterification reaction product and heat at 250°C.
The mixture was heated and dissolved in the presence of N2.

Ethylene glycol slurry in which the molar ratio of ethylene glycol to terephthalic acid was adjusted to 1.20 t was continuously supplied to the reactor, water was distilled off, and an esterification reaction was carried out. 105 parts by weight of the esterified product (
Ethylene terephthalate units (equivalent to 100 parts by weight) were charged into a polycondensation reaction apparatus, maintained at 250°C, and the ethylene glycol slurry of the particles produced in Example 1 was added as particles to 0.1 parts by weight (1 part by weight). Acetic acid power runium 005
1T+, m part, lithium acetate 1. o, 20 parts by weight, 0.15 parts by weight of trimethyl phosphate, 00 parts by weight of antimony trioxide
Add 3 tons of 1 it part and polymerize in a conventional manner until the intrinsic viscosity is 0.
．． 619 polymer 1:). The particle size in the polymer was palanque, and the particle dispersibility was first grade, which was good.

Claims (1)

[Claims] When manufacturing a polyester by transesterifying or esterifying terephthalic acid or its ester-forming derivative with a glycol and subsequently performing a polycondensation reaction, at any time before the start of the polycondensation reaction, outside the polyester synthesis reaction system. Then, particles produced by the reaction of terephthalic acid or a terephthalic acid derivative with an alkali metal compound and/or an alkaline earth metal compound are added, and an alkali metal compound and/or an alkaline earth metal compound are further added during the polycondensation reaction. A method for producing polyester, which comprises precipitating particles containing at least one kind of alkali metal and/or alkaline earth metal as a constituent component.