JPS62199649A - Production of fine particle dispersion for polyester - Google Patents

Abstract

PURPOSE:To produce a fine particle dispersion suitable for polyesters, by dispersing inert fine particles in a medium consisting essentially of a glycol and treating the resultant dispersion to deposit components different from the above- mentioned inert fine particles. CONSTITUTION:Particles, inert to a medium consisting essentially of a glycol and having <=10mum, preferably <=5mum, particularly <=3mum average particle diameter, e.g. magnesium oxide, silica, polyacrylic acid, etc., are uniformly dispersed in the above-mentioned medium using a homogenizer, etc., and insoluble components are uniformly deposited on the particle surfaces preferably dispersed in the medium by, e.g. a method for adding an aqueous solution of sodium tripolyphosphate to the above-mentioned dispersion and increasing the temperature to deposit the sodium tripolyphosphate, etc. There by the aimed fine particle dispersion having excellent compatibility with a polyester when added thereto is produced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing a fine particle dispersion for polyester. Specifically, the present invention provides a method for producing a fractional liquid of fine particles suitable for use in polyester by treating fine particles in a fractional liquid state and denaturing the fine particles.

More specifically, the modification (1) suppresses or prevents aggregation in the polymer when added to polyester.

(When added to phantom polyester, it improves compatibility with the polyester and prevents the formation of voids that occur in the surroundings of fine particles when the polyester is stretched. (3)
i! Improves the abrasion resistance of the final polyester product by reducing the surface hardness of one particle. (4) To provide a method for producing a fine particle fraction liquid that can produce effects such as being able to meet various market demands by changing the shape and particle size distribution of the fine particles.

(Prior Art) Generally, polyesters such as polyethylene terephthalate are widely used for fibers, films, and molded products because of their excellent physical and chemical properties. However, products obtained from polyester generally have a large coefficient of friction, have poor processability during spinning or film forming, and are also unfavorable in terms of handling of the product itself, causing deterioration in workability and reduction in product value. .

There is a strong desire to establish a method for producing polyester that provides a product with a low coefficient of friction and excellent slipperiness.

Generally, as a method for improving the slipperiness of polyester fibers or films, a method is adopted in which insoluble fine particles are mixed with polyester to form fine irregularities on the surface of the fibers or films.

Such fine particles include inorganic particles such as titanium dioxide, kaolinite, talc, silica, calcium carbonate, barium sulfate, etc. that are inert to polyester, and organic particles such as polymeric compounds such as styrene-divinylbenzene copolymer. particles are used. Furthermore, in order to improve the fractional nature of the particles in the polyester, a method has been adopted in which the particles are added to the polyester manufacturing process in a fractionated state in a medium mainly composed of glycol.

However, these fine particles generally have poor compatibility with polyester, and may aggregate during the polyester manufacturing process to generate coarse particles, or voids may occur around the particles during the stretching process during spinning or film forming. This causes the problem.

When coarse particles are generated, they cause clogging of filters in the polymerization process, silk spinning process, film forming process, etc., resulting in a reduction in filter life, and in the case of sheets or films that cause yarn breakage during spinning. is undesirable because it forms coarse protrusions and causes dropouts when used, for example, in magnetic tape applications. Further, the occurrence of voids is not preferable because it causes problems such as a decrease in abrasion resistance during passing through the process, or a decrease in the transparency of the product when it is made into a film.

As a way to solve this problem, it is possible to improve the fractionability in polyester by using a dividing agent when fractionating fine particles into a medium, or by adding a fractionating agent together with the fractional liquid when adding the fractional liquid to the polymerization process. A method has been adopted to improve compatibility with polyester and polyester. However, it is preferable not to add these dispersants because they have poor stability and cause discoloration of the product and a decrease in thermal properties and electrical properties.In addition, the above-mentioned fine particles generally have the disadvantage of high hardness. There is. If the hardness is high, the wear resistance of the product will decrease,
Alternatively, it is undesirable because it accelerates the wear of guides and caps during yarn spinning and film forming processes.

As a method for solving this problem, a so-called internal particle method has been proposed in which a carboxylic acid component, an oligomer, or a phosphorus compound is reacted with a metal compound to form fine particles during the polyester production reaction. It is true that the internal particle method is an excellent method in terms of low hardness and good compatibility with polyester, but in order to keep the amount of fine particles precipitated and particle size constant at all times, the polymerization conditions must be strictly controlled. It is necessary to control the amount, and even if this method is used, it has the disadvantage that coarse particles are likely to be formed.

In order to meet even more diverse product needs, it is necessary to revive the technology to arbitrarily control the shape, average particle size, particle size distribution, etc. of the fine particles. For this purpose, it is necessary to carry out pulverization, classification, etc., and the process of preparing the fraction liquid becomes extensive, resulting in a problem that it is inferior in terms of economic efficiency.

(Problems to be Solved by the Invention) The purpose of the present invention is to improve the drawbacks of the prior art described above, and (1)
) Suppresses or prevents agglomeration in the polymer when added to polyester. (2) When added to polyester, it improves compatibility with the polyester and suppresses the formation of voids that occur around the fine particles when the polyester is stretched. (3) Improve the abrasion resistance of the final polyester product by reducing the surface hardness of the microparticles. (4) To provide a method for producing a fraction of fine particles that can produce effects such as being able to meet various market demands by changing the shape and particle size distribution of the fine particles.

(Means for Solving the Problems) That is, 1. The present invention provides the following: In a medium containing glycols as a main component,
This is a method for producing a fine particle dispersion for polyester, characterized in that a component different from the inert particles is precipitated in a system in which particles with an average particle diameter of 10 μm or less coexist in the medium.

The particles having an average particle diameter of 10 μm or less in the present invention may be inorganic particles or organic particles as long as they are inert to the medium.

Inorganic particles include oxides of group III, group III and group III metals,
hydroxides, phosphates, sulfates and carbonates, such as magnesium oxide, alumina, titanium oxide, zirconium oxide, silica, zinc oxide, kaolinite, calcined seaweed. Examples include talc, lithium phosphate, calcium sulfate, barium sulfate, calcium carbonate, barium carbonate, and the like. Examples of the residual particles include fine polymer particles such as styrene-divinylbenzene copolymer, polyacrylic acid, and epoxy resin. The average particle diameter is preferably 5 μm or less, more preferably 3 μm or less. These fine particles may be used alone or in combination of two or more.

Glyco-/'M used as a medium includes ethylene glycol-μ, propylene glycol/I/, butylene glycol, etc., and two or more of these may be used in combination. It is particularly preferable to use the same glycol as the glycol used as a raw material for producing polyester, since deterioration in polymer quality and process contamination can be prevented. Further, water, a lower alcohol such as methanol or ethanol, a low boiling point solvent such as acetone, or MEK may be mixed and used as long as it is 50% or less.

The method for dispersing the fine particles in the solvent is not particularly limited, and any known method can be used.

Examples include a method of high-speed stirring using a device such as a homogenizer, a method of fractionating using a high-pressure homogenizer, and a method of dispersing by irradiating ultrasonic waves. These methods may be used alone or in combination of two or more methods.

Further, the dispersion conditions may be appropriately optimized depending on the type of fine particles to be dispersed. It is okay to use a dispersant during the dispersion, but there is no problem in not using a dispersant, so by optimizing the 1-minute sheet method and the 1-minute teaching conditions, 9. Disperse as uniformly as possible without using a dispersant. is preferable.

The medium-insoluble component to be precipitated in the medium may be an inorganic compound, a W organic compound, or a mixture of both. There are no particular limitations on the method for precipitating the component in a medium, but methods include (1) generating an inert compound through a chemical reaction, (2) irradiation with active energy rays such as light or electron beams, heat, etc. Cine solubilization occurs by applying energy to the system and changing its chemical structure. (3
) By applying energy to the system by irradiation with active energy rays such as light or electron beams, heat, etc., the crystal structure changes and becomes insolubilized. (4) Insolubilization using the solubility difference, etc. can be mentioned.

Methods of insolubilization through chemical reactions include hydrolyzing metal compounds soluble in a medium to form metal hydroxides or oxides, or insoluble metals by reaction with phosphoric acid, sulfonic acid, and their derivatives, etc. Examples include a method of forming a salt, and a method of forming a metal salt containing a polyester-forming component by reacting a metal compound with a polyester-forming raw material or a phosphorus compound. More specifically, it hydrolyzes metal alkoxides of Groups 1, 2, and 2, or lower fatty acid salts of the same metals.

Examples include reactions with phosphoric acid, sulfonic acid, and derivatives thereof. Also number 1. A method of producing a metal salt containing a polyester-forming component by reacting a lower fatty acid salt of a π- and N-group metal with a polyester-forming dicarboxylic acid, an ester derivative or oligomer of the dicarboxylic acid, or by reacting these compounds with a phosphorus compound. etc. In particular, a metal salt containing a polyester-forming component is a particularly preferred method since it is compatible with polyester and provides a product with low hardness.

One method is to change the chemical structure of the system by applying energy to the system through irradiation with active energy rays such as light or electron beams, heat, etc., thereby making it insolubilizable.

For example, a method may be mentioned in which a hexamer or oligomer having an active bond is subjected to a polymerization or crosslinking reaction. The active bond is preferably a vinyl group or an acrylate group. This method is suitable as a method for forming an organic insoluble component. Furthermore, the method of introducing an active group into an oligomer to form a polyester to make it insolubilized is particularly suitable in terms of improving compatibility with the polyester. As a method of insolubilizing the p-system by changing its crystal structure by applying energy to the p-system by irradiating energy beams such as light or electron beams or heat, for example, Japanese Patent Application Laid-Open No. 60-65058
Examples of methods that utilize the solubility difference include methods that utilize the solubility difference, such as the method disclosed in O. In the former case, it is preferable to use a compound whose solubility is reduced by mixing with glycols, and in the latter case, by increasing the temperature, the compound can be precipitated. Examples of compounds exhibiting such behavior include alkali metal phosphates. These methods may be used alone or in combination of two or more methods. A method of combining two or more types is a more preferable method because it allows for a variety of responses.

There are no particular limitations on the conditions for precipitating components insoluble in the dispersion using the above method, but for example, the temperature conditions are at least below the boiling point of the glycols, preferably below 100°C;
More preferably, the treatment is carried out at a temperature of 70°C or lower. It is not preferable to treat and precipitate at high temperatures because agglomeration of fine particles will occur.

The precipitation treatment for precipitating components insoluble in the medium may be carried out when the fine particles are fractionated into the medium, or may be carried out after the fractionation has been sufficiently carried out. The latter method is particularly preferred because the effects of the method of the present invention can be more clearly and reliably manifested by precipitating the insoluble components as uniformly as possible on the particle surfaces of the fine particles fractionated in the medium.

If it is necessary to supply energy for precipitation, the energy may be applied externally or the energy generated when fractionating fine particles may be used. The latter method is preferable in terms of energy saving.

The ratio between the amount of fine particles to be fractionated into the medium and the amount of insoluble components to be precipitated in the medium is not particularly limited, and it depends on the type and size of the fine particles, the structure of the insoluble components, the precipitation conditions, the effect to be achieved, etc. It can be selected by considering and optimizing it as appropriate. For example, in order to achieve an aggregation prevention effect or an effect of improving compatibility with polyester, it is sufficient to precipitate a very small amount of insoluble components, and a significant effect can be achieved with precipitation of 10% by weight or less based on the fine particles. . On the other hand, in order to reduce the surface hardness or change the shape and particle size distribution of the fine particles, it is necessary to precipitate insoluble components of 10% by weight or more based on the charged fine particles.

The fractionated liquid obtained by fractionating fine particles is pulverized, classified, and crushed in order to optimize the average particle size and particle size distribution, or to reduce coarse particles.
Operations such as filtration may be performed.These operations may be performed before or after precipitating the insoluble components. The fine particle dispersion of the present invention is added to the polyester manufacturing process.

Polyesters are usually polycarboxylic acids such as terephthalic acid and /'! It is produced by producing a low polymer by esterification or transesterification reaction or the like from an ester-forming derivative thereof and a polyhydric alcohol such as ethylene glycol, and then carrying out a polycondensation reaction.

It can be added at the initial stage of the amm molecular separation liquid polyester manufacturing process of the present invention, but it can be added from before the start of the esterification or transesterification reaction until the inherent viscosity exceeds 0.2. is preferred.

If the intrinsic viscosity exceeds 0.2, the viscosity of the reaction solution will be high, particles will not be mixed uniformly, a homogeneous product will not be obtained, or the glycols added as a dispersion may cause depolymerization. This is not preferable because it reduces the productivity of polymerization and increases the by-product of DEG (diethylene glycol). The transesterification catalyst and polycondensation catalyst for producing polyester/L'al can be appropriately selected from conventionally known catalysts. In addition, an alkali metal compound, an alkaline earth metal compound, a phosphorus compound, etc. may be added to impart static and N-characteristic properties. Furthermore, there is no restriction at all in adding various additives to suppress side reactions during the polyester manufacturing process or to improve the stability of the polyester. A part of these additives may be mixed into the fine particle dispersion according to the present invention as long as it does not cause undesirable effects.

As a method for producing polyester, either a batch method or a continuous method can be applied.

(Example) Next, Examples and Comparative Examples of the present invention will be shown. All parts in the examples are by weight unless otherwise specified.

The measurement method used is shown below.

(1) Average particle size of one particle The value of 50% of the cumulative value of the equivalent spherical diameter distribution obtained by a centrifugal sedimentation type particle size distribution analyzer manufactured by Takasugi Seisakusho is used.

(2) Amount of Precipitated Insoluble Components The dispersion is ultracentrifuged at 80,000 OOG, and the weight of the centrifuged sediment is precipitated! Calculated from the change in gravity fIk after 1t1.

(3) Number of coarse agglomerated particles in polyester Sandwich the polymer between two sheets of aluminum foil.

A sheet having a thickness of about 310 μm is produced by pressing at a temperature of 285° C. The sheet is simultaneously stretched by 3.5 times in the longitudinal and transverse directions at a temperature of 95° C. to obtain a stretched sheet having a thickness of about 25 μm. The stretched sheet was observed with a polaroscope, and the number of foreign particles shining in the black ink was counted per 100 d.

(4) Coefficient of dynamic friction of film According to ASTM-D-1894-637, 23°C.

Measurement is performed under the conditions of 65% RH and a tensile speed of 200 m/min.

(5) Observation of voids in the film The film was etched with an alkali to remove the surface polymer, and the fine particles were exposed and then observed with a scanning electron microscope to determine the presence or absence of voids.

Example 1゜(1) Preparation method of dispersion 1 θ part of silica manufactured by a wet method with an average particle size of 2.5μ and 90 parts of ethylene glycol were stirred at high speed for 2 hours in a trahomogenizer, and the silica was mixed with ethylene glycol-1v ( EG)
It was dispersed into During this time, cool the container with cold water and keep it at the same temperature for 25 minutes.
Keep at 9°C. To the dispersion was added 3.8' parts of a sodium tripolyphosphate solution dissolved in water at an aEt of 130 t/J, cold water cooling was changed to hot water heating, and high speed stirring was continued at 70° C. for 4 hours.

Sodium tripolyphosphate was precipitated. The amount of insoluble components extracted by the stirring treatment was 3.7% by weight based on the charged ylJ capacity.

(2) Method for producing polyester A continuous esterification reactor consisting of a two-stage complete mixing tank equipped with a 1-minute stirring device, a raw material inlet, and a product outlet is used, and the ester in the first esterification reactor is The molar ratio of EG to TPA to the system where the reaction product is present is 1.
．． E of TPA adjusted to 7 and containing 289 ppm of antimony dioxide per TPA unit as antimony atoms.
G slurry was continuously supplied.

At the same time, the EG bath solution of magnesium acetate tetrahydrate passes through the reactor through a supply port different from the TPA EG slurry supply port.
The mixture was continuously supplied at a concentration of 100 ppm as atoms, and the reaction was carried out at normal pressure for an average residence time of 4.5 hours and at a temperature of 255°C.

This reaction product is continuously taken out of the system.

It was supplied to the second esterification reactor. 0.5 parts by weight of EG per polyester ρ unit in the reaction product passing through the second esterification reactor, 64 ppm as P atoms in the EG bath solution of
) The EG fraction of the silica prepared in
ppm, respectively from separate supply ports, and at normal pressure, average residence time F [5,0 hours, temperature 2
React at 60℃ to form a circle.

The esterification rate of the reaction product in the first esterification reactor is 7
0%, and the esterification rate of the reaction product in the second esterification reactor was 98%.

The esterification reaction product is mixed with a stirring device and a partial condenser.

Continuously supplies polycondensation to a two-stage continuous tsi synthesis reactor equipped with a raw material inlet and a product outlet, producing polyester with an inherent viscosity of 0.620.The number of coarse particles in the polyester is 2 pieces/100-de! Comparative Example 1 A polyester was produced in the same manner as in Example 1, except that an aqueous solution of sodium tripolyphosphate was not added when preparing a silica dispersion using the same method as in Example 1. The number of coarse particles in the obtained polyester was 500 particles/100- or more, and the number of aggregated particles was extremely large.

Example 2゜(1) Preparation method of dispersion liquid Wet separation and classification using centrifugal liquid resulted in an average particle size of 1
．． 2μ calcium carbonate ethylene glycol dispersion (
l for 100 parts of calcium carbonate 0 degrees 100f/1)
30 f/1Ddlff? 3.8 parts by volume of a sodium tripolyphosphate solution dissolved in water was added, and the mixture was stirred at high speed with a homogenizer at 70° C. for 4 hours to precipitate non-porous components. The amount of insoluble components extracted was 3.5% by weight based on the amount of calcium carbonate charged.

(2) Production of polyester In the method of Example 1, the addition of the silica dispersion was stopped, and instead, the fractional solution fci of calcium carbonate prepared in (1) was added.
2000 pp as carbonic power I%/Vum for the polyester unit in the reaction product passing through the reactor.
A polyester was produced in the same manner as in Example 1, except that the amount of polyester was changed to m.

The polyester was melt extruded at 290°C.

3.5 times in the vertical direction at 90℃, 3.5 times in the horizontal direction at 130℃
After being stretched twice, heat treated at 220℃ to make a 12μ film.
-I got it. It was observed that there were only a few very small voids in the void 1 of the film, and the affinity of the lubricant was good.

Comparative Example 2 A polyester film was produced in the same manner as in Example 2, except that an aqueous solution of sodium tripolyphosphate was not added when preparing the calcium carbonate dispersion in the same manner as in Example 2. When the voids in the obtained polyester film were observed, many voids were found to be 2 to 3 times the size of the carbonic acid particles.

The affinity of the lubricant was extremely poor.

Example 3゜(1) Power of polyester oligomer/L/VumW
Preparation of ISM: In a container equipped with a stirrer and a reflux tube, add 1 part calcium acetate.
A solution prepared by dissolving 8.0 parts of hydrate in 122.8 parts of EG and 17.3 parts of bishydroxyethyl terephthalate were charged and reacted by heating and stirring at 182 to 192°C for 4 hours.

84 parts of EG was added to 16 parts of the reaction solution containing the obtained white reaction product, and the mixture was allowed to cool to room temperature while stirring, resulting in a transparent solution. The solution was filtered through a filter having a pore size of 0.5μ to remove trace amounts of insoluble matter.

(2) Dispersion preparation method In the dispersion preparation method of Example 1, instead of the sodium tripolyphosphate aqueous solution, 90 parts of the polyester oligomer salt solution prepared by the method (1) above is added. A dispersion was prepared in the same manner as in Example 1 except for the following. The amount of insoluble component extracted by this preparation method was 7.5
It was a good idea.

(3) Method for producing polyester μ Polyester μ was prepared in the same manner as in Example 1, except that the dispersion prepared in (2) above was used as the dispersion. The number of coarse particles in the obtained polyester was 3 particles/100-, and the number of di-agglomerated particles was extremely small.

Example 4 The method of Example 2 was repeated except that the addition of the sodium tripolyphosphate aqueous solution during the preparation of the dispersion was replaced with the addition of 50 parts of the calcium salt solution of the polyester oligomer prepared in (1) of Example 3. A polyester film was produced by the same method. Observation of voids in the obtained film revealed that only a few very small voids were present, indicating good compatibility with the lubricant.

Example 5゜(1) Preparation method of dispersion A solution of 0.83 parts of magnesium acetate tetrahydrate dissolved in 10 parts of wet-processed silica having an average particle size of 25 μm and 90 parts of EG. was stirred at high speed with a homogenizer for 2 hours, and the silica was fractionated into an EG solution containing magnesium acetate tetrahydrate. During this time, cool the container with cold water and use the same temperature t-25.
It was kept at ℃. A solution in which 0.61 parts of phenylphosphophone (1112) and 2 parts of EGK were dissolved was added to the dispersion, cooling was stopped, and high-speed stirring 1 was continued, and the temperature of the liquid was gradually raised by the heat generated by stirring, which took 2 hours. The temperature was then raised to 60°C. Stirring was continued at the same temperature for another 1 hour. The insoluble component analysis due to the stirring process was 6% for the charged silica ff1K.
．． The weight was 8 weight.

(2) Method for producing polyester A polyester was prepared in the same manner as in Example 1, except that the dispersion prepared in (1) above was used as the dispersion. The number of coarse particles in the obtained polyester was 5/100cr
I4, and there were very few aggregated particles.

(Effect of sprouting) By adding the dispersion of dead particles obtained by the method of the present invention to polyester, (1) aggregation in the polymer is suppressed or prevented. (2) It improves compatibility with polyester and suppresses the formation of voids that occur in the N edges of the sludge particles when the polyester is stretched. (
3) Reduce the surface hardness of the ridge particles to improve the abrasion resistance of the final polyester product. (4) By changing the particle shape and particle size distribution t-, there are effects such as being able to respond to various market demands.

Claims (1)

[Claims] A polyester product characterized in that a component different from the inert particles is precipitated in a medium containing glycol as a main component, in which inert particles with an average particle diameter of 10 μm or less coexist with the medium. A method for producing a fine particle dispersion.