JP2001214066A - Method for producing spherical microparticles of thermoplastic polycondensate resin and dispersion of the microparticles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for easily, efficiently, and industrially producing the subject high-quality spherical microparticles with high heat resistance and chemical resistance. SOLUTION: This method for producing the subject spherical microparticles comprises the following process: the monomers and/or oligomers for the aimed thermoplastic polycondensate are dispersed in a polysiloxane substantially inert to the thermoplastic polycondensate and subjected to thermal polymerization at such a temperature as to melt or soften the monomer and/or oligomer and the resulting thermoplastic polycondensate, the resultant system is then cooled, and the objective spherical microparticles thus formed are separated from the polysiloxane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel method for polymerizing spherical fine particles of a thermoplastic polycondensate resin. These spherical fine particles are used as a material for powder molding, a raw material for sinter molding, a filler for thermoplastic polycondensate resin and thermosetting resin, a filler for paint, a filtering agent, an adsorbent for analytical columns, a spacer for liquid crystal,
It is useful for toners, powder coatings, cosmetic bases, and the like.

[0002]

2. Description of the Related Art In general, as a method for producing fine particles made of a thermoplastic polycondensate resin, a method of mechanically pulverizing a solid polymer is known.

[0003] However, it is difficult to obtain fine particles having a uniform particle size by this method, and a special process such as a classifier is required to achieve the object. Further, it was more difficult to obtain fine particles having a uniform shape (for example, spherical).

[0004] In the case of vinyl polymers, the suspension polymerization method is known, and this method can solve the problem of uniform particle diameter to some extent, and can also obtain spherical particles.

However, in this method, applicable materials are limited to polymers derived from vinyl monomers.

On the other hand, there is an increasing demand for heat resistance, chemical resistance, abrasion resistance, etc., which cannot be met by vinyl polymers.

[0007] A number of attempts have been made to date for methods other than the above suspension polymerization method, for example, for obtaining spherical fine particles of a thermoplastic polycondensate resin.

[0008] For example, Japanese Patent Publication No. Hei 12-12975 discloses that polyethylene terephthalate having a reduced viscosity of less than 0.25 is melted by heating and then sprayed from a nozzle.
A method for obtaining a spherical polyester resin is described. Further, Japanese Patent Application Laid-Open Nos.
No. 26025 describes a method of treating a polymer composition heated and melted by an atomizer having a special orifice.

[0009] However, these methods have practical problems, such as requiring special equipment and being limited to resins having a low polymerization degree or low melt viscosity.

Until now, the most frequently studied method is to obtain a spherical fine particle by dissolving a thermoplastic polycondensate resin in an organic solvent or the like, heating and melting the resin, and then cooling and precipitating the resin.

With respect to nylon, a nylon resin powder is heated and dissolved in a solvent such as lower alcohol,
A method of gradually re-precipitating by cooling is used, and the powder is used as a powder coating, a cosmetic base, and an adsorbent. A further improved production method is disclosed in JP-A-63-186738.
In Japanese Patent Application Laid-Open Publication No. H11-163, a method for directly producing spherical nylon fine particles having a narrow particle size distribution is proposed.

Condensed polymers such as polyester and polycarbonate are disclosed in JP-A-51-79158, JP-B-60-31212, and JP-B-60-31.
No. 213 discloses poly (alkylene terephthalate)
With a halogenated aromatic solvent, tetrachloroethane, boiling point 2
A method is disclosed in which a spherical powder is obtained by heating and dissolving in an aromatic solvent at 30 ° C. or higher and then cooling.

Japanese Patent Application Laid-Open No. 2-215838 discloses that polyesters, polyamides and polycarbonates having a melting point higher than their melting points are referred to as "intermediate solvents" such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dimethyl adipate, dimethyl glutarate. Esters, dimethyl succinate, monoethylene glycol, diethylene glycol, triethylene glycol,
A method is described in which a non-aggregated particle is obtained by heating and dissolving with a solvent such as tetraethylene glycol and then cooling it under conditions that cause solid / liquid phase separation.

However, except for nylon, these methods are limited to crystalline resins which have a long time to precipitate fine particles, have a low yield relative to the charged polymer amount,
There are practical problems such as a step of extracting the solidified organic solvent with another organic solvent, a complete spherical fine particle cannot be obtained, and the obtained particle is mechanically brittle.

As another method, a method is disclosed in which a polymer is treated in an incompatible medium to obtain spherical fine particles.

For example, Japanese Patent Application Laid-Open No. 61-57617 discloses a method of obtaining a functional powder by vigorously stirring a thermoplastic resin in a medium in which the thermoplastic resin does not dissolve at a temperature higher than the melting point and then cooling the mixture. Have been. However, in the method using polyethylene glycol described above, only a copolymerized polyester having a low melting point can be micronized, and it is difficult to apply the method to a general-purpose thermoplastic resin having a high melting point.

Japanese Patent Application Laid-Open No. 7-3033 discloses that a liquid crystalline polymer having self-orientation is heated and extruded in a non-liquid crystalline polymer soluble in a solvent at a temperature at which liquid crystallinity can be maintained. After that, a method of obtaining a fine particle spherical body by removing the solvent is disclosed. In this method, in order to remove the solvent, there are problems that a large amount of a toxic solvent such as trifluoroacetic acid, which is highly toxic to the human body, must be used, and it takes a long time for extraction.

As described above, at present, an effective method for obtaining spherical fine particles of a thermoplastic polycondensate resin has not yet been found.

[0019]

DISCLOSURE OF THE INVENTION The present invention includes spherical fine particles of a thermoplastic polycondensate excellent in heat resistance and chemical resistance, spherical fine particles mainly containing a thermoplastic polycondensate, and thermoplastic polycondensates. The object of the present invention is to provide a method for industrially producing spherical fine particles simply and efficiently.

[0020]

Means for Solving the Problems The present inventors have conducted intensive studies to develop a method for industrially producing spherical fine particles of a thermoplastic polycondensate resin having the above-mentioned preferable properties. The monomer and / or oligomer of the condensate is heated and polymerized while being forcibly dispersed in a specific polymer heating medium within a specific temperature range, and after quenching, without extracting an incompatible polymer heating medium. It has been found that the purpose can be achieved by using a non-reactive polysiloxane at the time of separation, and the present invention has been accomplished based on this finding.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS That is, the present invention is as follows. In the specification of the present application, (A) according to the present invention
The symbols of the thermoplastic polycondensate resin (F) have the following meanings unless otherwise specified. (A): a monomer and / or oligomer for a thermoplastic polycondensate. Polysiloxane (B): a polysiloxane,
A thermoplastic polycondensate (E) formed by the polymerization of (A), wherein (A) is melted or dissolved in the polysiloxane;
At a temperature at which is melted or softened, the polysiloxane does not substantially react with (A) and does not substantially react with the melted or softened thermoplastic polycondensate (E), Those which do not substantially dissolve the softened thermoplastic polycondensate (E). Reactive silane compound (C): Reactive silane compound. Mixture (D): A mixture comprising (A), polysiloxane (B) and optionally a reactive silane compound (C). Thermoplastic polycondensate (E): a thermoplastic polycondensate formed by polymerization of (A). Thermoplastic polycondensate resin (F): a thermoplastic polycondensate resin obtained by polymerizing (A) while mixing the mixture (D).

In some cases, the thermoplastic polycondensate resin (F) is substantially the same as the thermoplastic polycondensate (E).

That is, the present invention provides spherical fine particles composed of a thermoplastic polycondensate having excellent heat resistance and chemical resistance, spherical fine particles mainly containing a thermoplastic polycondensate, and spherical fine particles containing a thermoplastic polycondensate. This is a simple and efficient method for industrial production.

In the present invention, "(1) a monomer and / or oligomer for a thermoplastic polycondensate (A) and (2) a polysiloxane, wherein (A) is melted or At a temperature at which the thermoplastic polycondensate (E) formed by dissolution and polymerization of (A) melts or softens, the polysiloxane does not substantially react with (A) and melts or softens. (B) which does not substantially react with the existing thermoplastic polycondensate (E) and does not substantially dissolve the molten or softened thermoplastic polycondensate (E); The step of polymerizing (A) while mixing the mixture (D) containing the reactive silane compound (C) to form a dispersion of spherical fine particles of the thermoplastic polycondensate resin (F) " Dispersion / polymerization process " There is a case.

In the above invention, since the thermoplastic polycondensate (E) to be formed is not again dissolved by heating in a solvent, problems associated with the “process of dissolving a polymer in a solvent and then depositing” are avoided. Has the features that can be.

The following characteristics can be obtained by using the polysiloxane (B).

Since the monomer and / or oligomer (A) can be easily dispersed or dissolved in the polysiloxane (B), heat transfer for accelerating the reaction is facilitated.

By-products, such as water, produced by the polymerization reaction are often poorly soluble in polysiloxane, and can be easily removed.

When the polysiloxane (B) is incompatible with the monomer and / or oligomer (A), fine particles can be formed by a mixing operation that does not give a large shear force to (A), and this is polymerized. By doing
At any stage, fine particles of the thermoplastic polycondensate resin (F) may be obtained without giving a large shear force. (However, even in this case, it is needless to say that mixing giving a large shear force may be performed.) Here, the term “large shear force” refers to a rotation of 1000 rotations (1000 rpm) or more per minute. It means a mixing operation using a stirring blade or a mixing operation equivalent to this.

As a general theory, the thermoplastic polycondensate resin (F) can be dispersed easily and unpredictably by a conventional dispersion method such as the case of polyethylene glycol.

The treatment can be performed stably even at a considerably high temperature.

[0032] Cooling, washing and separation of the fine particles become extremely easy.

Hereinafter, the present invention will be described in detail. The present invention is as follows.

1. (1) a monomer and / or oligomer (A) for a thermoplastic polycondensate, and (2) a polysiloxane, wherein (A) is melted or dissolved in the polysiloxane and polymerized by (A) At a temperature at which the resulting thermoplastic polycondensate (E) melts or softens, the polysiloxane does not substantially react with (A),
(B) which does not substantially react with the molten or softened thermoplastic polycondensate (E) and does not substantially dissolve the molten or softened thermoplastic polycondensate (E);
(3) A method for producing a spherical fine particle dispersion of a thermoplastic polycondensate resin (F) in which a mixture (D) containing an optional reactive silane compound (C) is mixed while polymerizing (A).

2. (1) a monomer and / or oligomer (A) for a thermoplastic polycondensate, and (2) a polysiloxane, wherein (A) is melted or dissolved in the polysiloxane and polymerized by (A) At a temperature at which the resulting thermoplastic polycondensate (E) melts or softens, the polysiloxane does not substantially react with (A),
(B) and (3) which do not substantially react with the molten or softened thermoplastic polycondensate (E) and do not substantially dissolve the molten or softened thermoplastic polycondensate (E). )
While mixing the optional mixture (D) containing the reactive silane compound (C), the dispersion of the spherical fine particles of the thermoplastic polycondensate resin (F) obtained by polymerizing (A) is cooled. And a method for producing spherical fine particles of a thermoplastic polycondensate resin (F) which is separated from the polysiloxane.

3. 3. The method for continuously producing spherical fine particles according to the above item 2, wherein the mixing of (A), the polysiloxane (B), and the optional reactive silane compound (C) is performed by a stirrer having a high-speed shearing ability.

4. 4. The method for producing spherical fine particles according to the above 2 or 3, wherein the weight ratio between the thermoplastic polycondensate resin (F) and the polysiloxane (B) immediately before the cooling operation satisfies the following formula (A-1). 0.01 ≦ PP / (PP + SP) (A-1) (In the formula (A-1), PP represents the weight of the thermoplastic polycondensate resin (F), and SP represents polysiloxane ( Represents the weight of B))

5. The polysiloxane (B) has the following formula (1)

Embedded image

[In the formula (1), Si is a silicon atom.
R₁, R_Two, R_Three, R_Four, R_Five, R₆, R ₇And R₈Haso
Each independently represents a hydrogen atom, an OH group, an alkyl group having 1 to 10 carbon atoms.
Represents a kill group or an aryl group having 6 to 12 carbon atoms. m is
It is an integer of 1 to 300. 2 to 4 above
A method for producing spherical fine particles according to any of the above.

6. 6. The method for producing spherical fine particles according to the above 5, wherein the polysiloxane (B) is a polysiloxane represented by any of the following formulas (1-1) and (1-2) or a mixture of both.

[0041]

Embedded image

In the formulas (1-1) and (1-2), S
i is a silicon atom, and Ph is a phenyl group.
X, Y and Z are each an independent integer of 1 to 300. ]

7. The mixture (D) contains 0.001 to 10 parts by weight of the reactive silane compound (C) based on 100 parts by weight of the polysiloxane (B).
7. The method for producing spherical fine particles according to any one of 6.

8. 8. The method for producing spherical fine particles according to the above 7, wherein the reactive silane compound (C) is a silane coupling agent.

9. The silane coupling agent is represented by the following formula (3)
-1)

Embedded image 9. The method according to the above item 8, wherein the structure is represented by:

10. 10. The method for producing spherical fine particles according to any one of the above 2 to 9, wherein the thermoplastic polycondensate (E) is at least one polyester selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate.

11. The method for producing spherical fine particles according to any one of the above 2 to 9, wherein the thermoplastic polycondensate (E) is a polyetherester.

12. 10. The method for producing spherical fine particles according to any one of the above 2 to 9, wherein the thermoplastic polycondensate (E) is a polycarbonate.

13. The temperature Th1 or Th2 of the mixture (D) immediately before the cooling operation is determined by the following formula (B-1) or (B-
2) and the temperature Tq1 of the mixture (D) after cooling.
Alternatively, the method for producing spherical fine particles according to any one of the above 2 to 12, comprising a step in which Tq2 satisfies the following formula (C-1) or (C-2). Tm ≦ Th1 ≦ Tm + 50 (B-1) Tp−50 ≦ Th2 ≦ Tp + 50 (B-2) Tm−100 ≦ Tq1 ≦ Tm (C-1) Tp−100 ≦ Tq2 ≦ Tp (C-2) [In the formulas (B-1) and (C-1), Tm is the melting point of the obtained thermoplastic polycondensate (E), and is represented by the formula (B-2) And in the formula (C-2), Tp has a viscosity of 10 obtained by measuring the thermoplastic polycondensate (E) obtained using a Koka type flow tester at a pressure of 3.9 MPa and a nozzle of 1 mmφ × 10 mmL.
000 poise. All units are in ° C.
It is. The formulas (B-1) and (C-1) are used when the thermoplastic polycondensate (E) is crystalline having a melting point, and the formulas (B-2) and (C-2) are used. Is used when the thermoplastic polycondensate (E) is amorphous without a melting point. ]

In the present invention, the obtained thermoplastic polycondensate (E) is not particularly limited, whether it is crystalline or amorphous. However, preferred are polycarbonates, polyethylene terephthalate, polybutylene terephthalate, and the like. Polyesters such as polyethylene naphthalate, polyetherester, polyarylate and the like can be mentioned.

More preferred are polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate and polyetherester.

Each of these thermoplastic polycondensates (E) is a thermoplastic polymer produced by a known polymerization method, but it has been difficult to form spherical fine particles on an industrial level.

Monomer and / or oligomer (A)
What can give these thermoplastic polycondensates (E) is used.

With respect to the above-mentioned polyester monomers, there may be mentioned aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid.

As the aromatic dicarboxylic acid ester,
Dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dimethyl 2,6-naphthalenedicarboxylate, diethyl 2,6-naphthalenedicarboxylate, dimethyl 2,7-naphthalenedicarboxylate, and 2,7-naphthalenedicarboxy Examples thereof include diethyl acid.

These may have a substituent such as an alkyl group or a halogen on the aromatic ring. Of these, terephthalic acid, 2,6-naphthalenedicarboxylic acid, dimethyl terephthalate, and dimethyl 2,6-naphthalenedicarboxylate are preferred from the viewpoint of handling properties.

As the diol component, specifically, ethylene glycol, 1,4-butanediol, propylene glycol, 1,6-hexanediol (1,6-hexamethylene glycol), 3-methyl-1,5- Pentanediol and the like can be exemplified.

These may contain an ether bond and a thioether bond.

Among them, ethylene glycol, 1,6-hexanediol and 3-methyl-1,5-pentanediol are preferred.

In order to introduce an ether structure into the polymer main chain, polytetramethylene glycol, polyethylene glycol, poly (propylene oxide) glycol, an ethylene oxide adduct to bisphenols, poly (propylene oxide) glycol copolymerized polyethylene glycol Etc. can also be used.

Further, as an oligomer component, a form in which a diol is dimer-added to an aromatic dicarboxylic acid can be exemplified. In particular, for the polymerization of polyethylene terephthalate, bishydroxyethyl terephthalate, for the polymerization of polybutylene terephthalate,
Bishydroxybutyl terephthalate can be preferably used.

With respect to the above-mentioned monomers of polycarbonates, diphenyl carbonate and bisphenyl A as bisphenols may be mentioned.

In the polymerization of the thermoplastic polycondensate (E), two or more monomers and / or oligomers may be blended and used.

In order to react these monomers and / or oligomers rapidly, known catalysts can be used without any problem.

Specifically, as the transesterification catalyst,
Antimony compounds such as antimony trioxide, stannous acetate,
Examples include tin compounds such as dibutyltin oxide and dibutyltin diacetate, titanium compounds such as tetrabutyltitanate, zinc compounds such as zinc acetate, calcium compounds such as calcium acetate, and alkali metal salts such as sodium carbonate and potassium carbonate. be able to. Of these, tetrabutyl titanate is preferably used.

The amount of the catalyst used may be the amount used in a usual transesterification reaction, and is preferably 0.01 to 0.5 mol%, and more preferably 0.01 to 0.5 mol% with respect to 1 mol of the acid component or ester component used. ~ 0.3 mol% is more preferred.

It is preferable to blow an inert gas in order to effectively carry out dehydration, methanol removal, glycol removal, and phenol removal accompanying polymerization and to remove by-products from the system. Examples of the inert gas include a nitrogen gas and an argon gas, and a nitrogen gas is preferable in terms of economy. In some cases, part or all of the polymerization reaction may be performed under vacuum instead of normal pressure. In some cases, it is also possible to carry out the reaction under pressure.

It is also preferable to use various stabilizers such as antioxidants described later.

The time required for the polymerization and the formation of fine particles depends on the thermoplastic polycondensate (E) to be produced, and is not particularly limited. In the case of a usual polyester, it takes 60 minutes until the monomer is charged and polymer spherical fine particles are obtained. It is generally performed in minutes to 180 minutes.

The polymerization time may be shorter than that of a known polymerization method performed under reduced pressure, even when the polymerization is carried out at normal pressure.

It is presumed that, as described above, the use of polysiloxane facilitates dehydration, methanol removal, glycol removal, and phenol removal in the polymerization reaction of monomers and / or oligomers.

In the present invention, the above-mentioned monomer and / or oligomer (A) is mixed, dispersed or dissolved in a polymer heating medium containing polysiloxane (B), and a polymerization reaction is carried out.

The polysiloxane (B) used here is a linear polymer whose main chain is mainly composed of repeating units represented by — (Si—O) —, and is a monomer and / or oligomer that undergo a polymerization reaction. At a temperature at which the polysiloxane melts or dissolves in the polysiloxane and the thermoplastic polycondensate formed by polymerization of the monomer and / or oligomer melts or softens, the polysiloxane and the monomer and / or oligomer are substantially dissolved. There is no particular limitation as long as it does not react and does not substantially react with the molten or softened thermoplastic polycondensate and does not substantially dissolve the molten or softened thermoplastic polycondensate. Can be used.

When the polysiloxane is dissolved and compatible with the above-mentioned thermoplastic polycondensate (E), the desired spherical particles cannot be obtained, but only an amorphous thermoplastic polycondensate resin powder can be obtained. Further, when reacting with the above-mentioned monomer and / or oligomer (A) or the above-mentioned thermoplastic polycondensate (E), a gel or the like is formed over the whole, and not only spherical resin particles cannot be obtained, but also the mixed system itself may be solidified. . As long as these properties are not impaired, the main chain may have another repeating unit, or may have a branched component.

As such a polysiloxane, for example, the following formula (1)

Embedded image Can be mentioned.

In the above formula (1), Si is a silicon atom, and R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are each independently a hydrogen atom, an OH group, Represents an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 12 carbon atoms. m represents an integer of 1 to 300. Examples of such an alkyl group include a methyl group and an ethyl group. Examples of the aryl group include a phenyl group, a tolyl group, and a naphthyl group.

As a more specific example of the above formula (1),
Polysiloxanes represented by the following formulas (1-1) and (1-2) are more preferable.

[0078]

Embedded image

In the above formulas (1-1) and (1-2), P
h represents a phenyl group, and CH ₃ represents a methyl group. X, Y and Z each represent an independent integer of 1 to 300.

The above 13. , Tm is the melting point of the obtained crystalline thermoplastic polycondensate (E) determined by differential scanning calorimetry (DSC), Tp is the softening temperature, and Shimadzu Corporation Pressure of 3.9 Mpa using a chemical flow tester, nozzle 1 mm
The temperature at which the viscosity measured at φ × 10 mmL indicates 10,000 poise.

If Th1 is smaller than Tm, the thermoplastic polycondensate resin cannot be dispersed, or the thermoplastic polycondensate (E) produced from the monomers and / or oligomers solidifies before becoming a sufficient size. In some cases, particles having a desired particle size cannot be obtained. Th2 is (Tp-50) ° C
If the particle size is smaller than the above, there may be a problem that the shape of the obtained fine particles is not spherical, or the fine particles easily aggregate during the forced dispersion, and a massive thermoplastic resin is obtained as an impurity.

If Th1 is higher than (Tm + 50) ° C. or Th2 is higher than (Tp + 50) ° C., decomposition of the thermoplastic polycondensate resin (F) forming fine particles occurs.
There are problems such as deterioration of mechanical properties such as strength of the obtained fine particles and generation of offensive odor due to decomposition during the formation process, which may be undesirable.

More preferably, a step satisfying the following formula (B-3) or (B-4) is included.
Alternatively, it is more preferable to include a step satisfying (B-6). All units are in ° C. Tm + 5 ≦ Th ≦ Tm + 40 (B-3) Tp ≦ Th ≦ Tp + 40 (B-4) Tm + 10 ≦ Th ≦ Tm + 30 (B-5) Tp + 10 ≦ Th ≦ Tp + 30 (B−) 6)

The weight ratio of the thermoplastic polycondensate resin (F) and the polysiloxane (B) immediately before the cooling operation is as follows:
It is preferable to satisfy the following formula (A-1): 0.01 ≦ PP / (PP + SP) (A-1) In the above formula (A-1), PP
Represents the weight (part) of the thermoplastic polycondensate resin (F) immediately before the cooling operation, and SP represents the weight (part) of the polysiloxane (B).

When the value of PP / (PP + SP) is smaller than 0.01, the productivity of the obtained spherical fine particles may be deteriorated.

More preferably, the following formula (A-2) is satisfied, and more preferably, the following formula (A-3) is satisfied. 0.03 ≦ PP / (PP + SP) ≦ 0.9 (A-2) 0.05 ≦ PP / (PP + SP) ≦ 0.8 (A-3) From 0.9 If the size is large, the shape of the obtained fine particles will not be spherical, or aggregation of the fine particles will easily occur during forced dispersion,
There are cases where there is a problem that a massive thermoplastic polycondensate resin may be obtained as an impurity.

[0086] Immediately before the cooling operation, the monomer and / or oligomer may substantially end the polymerization reaction, but this is not always necessary, and the monomer and / or oligomer may remain.

The unreacted monomers and oligomers are concentrated by some method and then mixed with polysiloxane to form a mixture.
It is one embodiment of the present invention to provide for the polymerization reaction. If the catalyst used in the polymerization reaction is more soluble in the monomer and / or oligomer than the thermoplastic polycondensate resin (F), the catalyst may be effectively recycled.

In the mixing / reaction / dispersion step, the melted or softened thermoplastic polycondensate (E) is mixed with the polysiloxane (B) using a stirrer or the like, and dispersed or dissolved. Here, as a device that can be used in the mixing / reaction / dispersion step, there can be mentioned, for example, a homogenizer in addition to an ordinary stirrer having a stirring blade.

The homogenizer can be roughly classified into two types: a mechanical stirring type and an ultrasonic type. In the present invention, both the former type and the latter type can be used without any problem. A mechanically agitated homogenizer is more preferred. In the case of the mechanical stirring type, it is preferable that the rotation speed satisfies the following formula (D-1) at least after the thermoplastic polycondensate resin starts to be generated. 5000 ≦ Rv ≦ 30000 (D-1) In the above formula (D-1), Rv represents the number of revolutions per minute (unit rpm) of the stirring blade of the mechanical homogenizer.

When the rotational speed Rv is less than 5000, the shape of the obtained spherical resin fine particles is not spherical, or the fine particles are easily aggregated during forced dispersion, so that a massive thermoplastic polycondensate resin is obtained as an impurity. Sometimes.

If the rotational speed Rv is greater than 30,000, the thermoplastic polycondensate resin forming the fine particles is decomposed, and the mechanical properties such as the strength of the obtained fine particles are deteriorated, and the particle distribution of the obtained spherical resin fine particles is reduced. In some cases, the polydispersity index dw / dn described later becomes large, which is not preferable.

Rv preferably satisfies the following formula (D-2), and more preferably satisfies the following formula (D-3). 8000 ≦ Rv ≦ 28000 (D-2) 10,000 ≦ Rv ≦ 25000 (D-3) In the present invention, at the time of the mixing / reaction / dispersion step,
In particular, when a polysiloxane (B) represented by the above formula (1) is used, a polydispersity index dw / dn of a particle size distribution described later is added by adding a reactive silane compound (C) into the system. Another characteristic of the present invention is that spherical tree particles having a particle size distribution closer to 1.0, that is, a relatively narrow particle size distribution with a uniform particle size can be obtained.

The reactive silane compound (C) is preferably a silane coupling agent, and the silane coupling agent is preferably an alkoxysilane compound having a glycidyl group, and is represented by the following formula (3-1). More preferably, the structure is

[0095]

Embedded image

Here, the reactive silane compound (C) is a silane compound having an organic reactive group and substantially reacting with an organic compound mainly containing carbon to form a covalent bond with the organic compound. It is a derivative. Examples of the silane derivative include alkylsilane, siloxane, polysiloxane, and polysiloxane oligomer. Specific examples of the organic reactive group include a carboxylic acid group, a carboxylic acid ester group, a hydroxyl group, a mercapto group, a glycidyl group, a vinyl group, an allyl group, an amino group, an isocyanate group, and a chloro group.

The addition amount of the reactive silane compound (C) is 0.01 to 1 with respect to the amount of the polysiloxane (B) used.
0 parts by weight is good. If the amount is less than 0.01 part by weight, the particle size distribution of the obtained fine particles tends to be wide. When the amount of addition is increased, it is easy to obtain one having a uniform particle size distribution. However, when the amount is too large, the thermoplastic polycondensate resin (F) may gel or generate an odor during dispersion. The upper limit is about 10 parts by weight. A preferable addition amount is 0.05 to 8 parts by weight, and a more preferable addition amount is 0.1 to 5 parts by weight.

After the thermoplastic polycondensate (E) is sufficiently polymerized and dispersed in the polysiloxane (F) as described above, it is cooled.

As the cooling method, any method such as cooling with a heat exchanger or mixing with another liquid may be used. For example, the above-mentioned thermoplastic polycondensate resin (F) is dispersed and dispersed. It is a preferable method to introduce the same polysiloxane having a temperature of room temperature or lower into the system.

By rapidly cooling the temperature in the system in this manner, aggregation of the fine particles generated in the system is suppressed. The temperature Tq1 or Tq2 in this cooling step is
When the thermoplastic polycondensate (E) used is crystalline, the following formula (C-1) is used. When the thermoplastic polycondensate (E) used is amorphous, the following formula (C-2) is used. It is preferable to include a satisfying step. All units are in ° C. Tm-100 ≦ Tq1 ≦ Tm (C-1) Tp-100 ≦ Tq2 ≦ Tp (C-2) In the above formulas (C-1) and (C-2), Tm And Tp have the same meanings as in the above formulas (B-1) and (B-2).

Tq1 is smaller than (Tm−100) ° C.
Alternatively, when Tq2 is smaller than (Tp-100) ° C., the shape of the obtained spherical fine particles is not spherical, or the particle distribution of the obtained spherical fine particles is wide, and the polydispersity index dw /
dn may be undesirably large. Also, Tq
When 1 or Tq2 is larger than Tm or Tp, respectively, the shape of the obtained spherical fine particles may not be spherical,
Aggregation of the fine particles easily occurs during cooling, and a massive thermoplastic polycondensate resin may be obtained as an impurity.

More preferably, a step satisfying the following formula (C-3) or (C-4) is included.
Alternatively, it is more preferable to include a step satisfying (C-6). All units are in ° C. Tm-80 ≦ Tq1 ≦ Tm-10 (C-3) Tp-80 ≦ Tq2 ≦ Tp-10 (C-4) Tm-60 ≦ Tq1 ≦ Tm-30 ...・ ・ (C-5) Tp-60 ≦ Tq2 ≦ Tp−30 (C-6)

Here, the “mixture after cooling (C)”
In the case of cooling by a heat exchanger, the term "excluding the resin in the mixture containing the thermoplastic polycondensate resin (F) and polysiloxane" means that the mixture is brought into contact with another liquid containing polysiloxane. In some cases, this "other liquid" is also included. This solution is not necessarily one layer, but the temperature means its average value.

It is desirable to perform cooling immediately. The cooling can be performed with mixing by stirring or the like.
It is desirable that the time from Tq1 to Tq1 or from Th2 to Tq2 be short. Specifically, the time is preferably within 5 minutes, more preferably within 3 minutes, even more preferably within 1 minute.

By cooling, the time in the upper air temperature range is 1
More than a minute is appropriate. If the time is less than 1 minute, the thermoplastic polycondensate resin (F) is not sufficiently hard, and may be deformed or condensed later. 3 minutes or more is more desirable, and 5 minutes or more is even more desirable.

Next, the spherical fine particles are separated by filtration or the like. The liquid remaining on the separated spherical particles can be easily washed and removed with an organic solvent such as n-hexane or cyclohexane, and usually dried to obtain spherical fine particles.

According to the present invention, high-quality thermoplastic polycondensation which is excellent in heat resistance and chemical resistance, has a spherical shape with a diameter of 0.1 to 500 μm, is homogeneous, and has a relatively uniform particle size. Fine particles of body resin can be obtained. Such fine particles,
Preferably, they satisfy the following formulas (2-1) and (2-2). 0.90 ≦ Pn ≦ 1.00 (2-1) 1 ≦ dw / dn ≦ 2.0 (2-2) In the above formula (2-1), Pn is a reflection. Observation with a scanning electron microscope (S
EM), the size of which is 0.1 to
It is a number average roundness obtained by dividing the sum of the roundnesses P1 to Ph of n particles within a certain range of a photographed photograph by the number in the range of 500 μm.

In the above formula (2-2), dw / dn represents the polydispersity index of the particle size distribution measured by the light scattering / light diffraction method.

The light scattering / light diffraction method is a method for measuring the particle size distribution by utilizing the fact that the scattering pattern varies depending on the particle size. This is a known method for calculating the particle size distribution by calculating the content of each particle size closest to the actually measured scattering pattern using the calculated scattering patterns of various particle sizes.

From this, the polydispersity index dw / d is obtained by dividing the obtained weight average particle size dw by the number average particle size dn.
n is calculated.

In the production method of the present invention, various additives may be added to the mixing / reaction / dispersion step and the subsequent steps as needed. Such additives include, in addition to the reactive silane compounds described above, glass fiber, metal fiber, aramid fiber, ceramic fiber, potassium whisker, carbonate fiber, fibrous reinforcing agents such as asbestos, talc, calcium carbonate. , Mica, clay,
Various fillers such as titanium oxide, aluminum oxide, glass flake, milled fiber, metal flake, metal powder, heat stabilizers such as phosphate esters and phosphites, catalyst deactivators, oxidation stabilizers Additives such as a light stabilizer, a lubricant, a pigment, a flame retardant, a flame retardant auxiliary, and a plasticizer.

[0112]

According to the present invention, spherical fine particles composed of thermoplastic polycondensate, spherical fine particles mainly containing thermoplastic polycondensate, spherical fine particles containing thermoplastic polycondensate, above all, heat resistance and chemical resistance These spherical fine particles having excellent quality, small particle size and relatively uniform quality can be easily and efficiently industrially produced. Such spherical fine particles, powder molding material, raw material for sinter molding, filler of thermoplastic resin or thermosetting resin, filler of paint, filter agent,
It is useful for analytical column adsorbents, liquid crystal spacers, toners, powder coatings, cosmetic bases, etc.

[0113]

EXAMPLES Preferred embodiments of the present invention will be described below with reference to examples, but the present invention is not limited to the examples. In the examples, "parts" means "parts by weight" unless otherwise specified. In the examples, various measurements were made by the following methods.

(Reduced viscosity) Unless otherwise specified, this is a value measured at 35 ° C. in a mixed solvent of phenol / tetrachloroethane (weight ratio 60/40) at a concentration of 1.2 (g / dl).

(Number average roundness) Reflection electron microscope SEM
The photograph was taken using a scanning electron microscope S-2400 manufactured by Hitachi, Ltd.

In a SEM photograph image of 1000 times, 89 μ
For each of i particles observed in an area of mx 117 μm in width, each having a size in the range of 0.1 to 500 μm, the photograph is rotated by a rotary table, and the entrance and exit of the particles in the radial direction are measured with a micrometer. A polar coordinate recording figure excluding the influence of eccentricity of tracing and mounting is obtained, a concentric template is applied to the figure, a circumcircle radius Rmax and an inscribed circle Rmin are read by the minimum area method, and the following equation (5-1) is used. Thus, the roundness Pi of each i-th particle was determined (see FIG. 1). Pi = Rmin / Rmax (5-1) The number average roundness Pn is represented by the following equation (5-2). Pn = ΣnPi / Σni (5-2) (Measurement of polydispersity index dw / dn of fine particles) Measurement of polydispersity index dw / dn of fine particles by light scattering / light diffraction method is performed by Shimadzu. The measurement was performed using a laser diffraction particle size distribution analyzer SLAD-2000J manufactured by Seisakusho and using a 0.1% by weight aqueous solution of sodium hexametaphosphate as a dispersant.

The weight average particle size dw obtained by this measurement
Is divided by the number average grain system dn to obtain a polydispersity index dw.
/ Dn was calculated.

[Examples 1 to 3] A stainless steel container having a capacity of 500 ml was fixed, and a mechanical stirring type homogenizer was installed such that the stirring portion was located at the center of the bottom. Then, a reflux tube, a nitrogen inlet tube, and a sample inlet were provided on the upper part of the vessel, and a heating heater capable of controlling the temperature was attached to the outside of the vessel to perform a heat retaining process.

While introducing nitrogen into the system at 5 L / min, the polysiloxane A of the above formula (1-1) (SRX-310 manufactured by Dow Corning Toray Silicone Co., Ltd.)
40 parts, 10 parts by weight of bishydroxyethyl terephthalate (BHET: oligomer for polymerization of polyethylene terephthalate), 1 part by weight of the compound of the above formula (3-1) as a reactive silane compound, and 0.1 part of tetrabutoxytitanium as a catalyst. After adding 04 parts by weight, the mixture was stirred with a homogenizer at a rotation speed of 24300 rpm.

The heating was performed according to the time program shown in FIG. However, the polymerization time was 1.5 hours, 2.5 hours, and 3.5 hours for Examples 1 to 3, respectively. During this time, 2.2 to 2.4 parts by weight of ethylene glycol was distilled off.

After completion of the program, 100 parts by weight of a cooled polysiloxane at room temperature (20 ° C.) was added, and the stirring was terminated.
At this time, the temperature in the vessel dropped to around 210 ° C. within one minute. Thereafter, the temperature was maintained at 210 ° C. to 200 ° C. for 5 minutes, and then air-cooled to room temperature over 30 minutes, and the polyethylene terephthalate particles dispersed in the polysiloxane were separated by filtration.

The yield was 7 to 8 g, and the reduced viscosities of Examples 1 to 3 were 0.29, 0.44, and 0.50, respectively. The melting points Tm are 218 ° C. and 248 ° C., respectively.
° C and 251 ° C.

The obtained fine particles were spherical resin fine particles having a size of 1 to 100 μm from the SEM photograph. Table 1 shows an SEM photograph, an average particle diameter, a number average circularity, and the like of these spherical fine particles. The SEM photographs of Examples 1 and 2 are 50
The SEM photograph of Example 3 was at a magnification of 1000 times.

Example 4 11.2 parts by weight of diphenyl carbonate and 11.4 parts by weight instead of 10 parts by weight of BHET
The same treatment as in Example 2 was carried out, except that bisphenol A was used in an amount of 0.014 part by weight, and 9.5 g of phenol was distilled off. 0.0 g of polycarbonate spherical fine particles were obtained. The particles had a reduced viscosity of 0.55 and a Tp of 242 ° C. The obtained fine particles are S
From the EM photograph, it was spherical resin fine particles having a size of 1 to 100 μm. The average particle diameter was 58 μm, the number average circularity was 0.99, and dw / dn was 1.51.

Example 5 The same treatment as in Example 4 was carried out except that no reactive silane compound was used, and 9.5 g of phenol was distilled off to obtain 12.0 g of spherical polycarbonate fine particles. The particles had a reduced viscosity of 0.55 and a Tp of 242 ° C. The obtained fine particles are S
From the EM photograph, it was spherical resin fine particles having a size of 1 to 100 μm. Further, the average particle diameter was 58 μm, the number average circularity was 0.99, and dw / dn was 1.62.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for calculating a number average circularity Pn of spherical fine particles.

FIG. 2 is a temperature rise curve (time program) according to Examples 1 to 3.

FIG. 3 shows Table 1.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (reference) C08L 69/00 C08L 83/04 83/04 C08K 5/54 F term (reference) 4J002 CF06W CF07W CF08W CG02W CP03X EX036 EX066 GB00 GD02 GH01 HA08 4J029 AA03 AA10 AB04 AB07 AC01 AD01 AE11 AE18 BA02 BA03 BA05 BA07 BA08 BF25 CB06A CC05A CC06A HD04 JE182 JE223 KB06 KD17 KE10 KH04 4J031 CA07 CA12 CA37

Claims (13)

[Claims] (1) A monomer and / or oligomer (A) for a thermoplastic polycondensate, and (2) a polysiloxane, wherein (A) is melted or dissolved in the polysiloxane, and At a temperature at which the thermoplastic polycondensate (E) formed by polymerization of A) melts or softens,
The thermoplastic polycondensate, in which the polysiloxane does not substantially react with (A) and does not substantially react with the molten or softened thermoplastic polycondensate (E), (B) which does not substantially dissolve E) and (3)
A method for producing a spherical fine particle dispersion of a thermoplastic polycondensate resin (F), which comprises polymerizing (A) while mixing a mixture (D) containing an optional reactive silane compound (C). 2. A (1) monomer and / or oligomer (A) for a thermoplastic polycondensate, and (2) a polysiloxane, wherein (A) is melted or dissolved in the polysiloxane, and At a temperature at which the thermoplastic polycondensate (E) formed by polymerization of A) melts or softens,
The thermoplastic polycondensate, in which the polysiloxane does not substantially react with (A) and does not substantially react with the molten or softened thermoplastic polycondensate (E), A thermoplastic polymer obtained by polymerizing (A) while mixing a mixture (D) containing (B) which does not substantially dissolve E) and (3) an optional reactive silane compound (C) A method for producing spherical fine particles of a thermoplastic polycondensate resin (F), wherein the dispersion of the spherical fine particles of the polycondensate resin (F) is cooled and then separated from the polysiloxane. 3. The method of claim 2, wherein the mixing of (A), the polysiloxane (B) and the optional reactive silane compound (C) is by a stirrer having a high-speed shearing ability. Continuous manufacturing method. 4. The spherical fine particles according to claim 2, wherein the weight ratio between the thermoplastic polycondensate resin (F) and the polysiloxane (B) immediately before the cooling operation satisfies the following formula (A-1). Manufacturing method. 0.01 ≦ PP / (PP + SP) (A-1) (In the formula (A-1), PP represents the weight of the thermoplastic polycondensate resin (F), and SP represents polysiloxane ( Represents the weight of B)) 5. The polysiloxane (B) is represented by the following formula (1):[In the formula (1), Si is a silicon atom, and R₁, R_Two,
R_Three, R_Four, R_Five, R₆, R ₇And R₈Are each independently water
Elemental atom, OH group, alkyl group having 1 to 10 carbon atoms or carbon
Represents an aryl group having a prime number of 6 to 12. m is 1 to 300
Is a number. The method according to any one of claims 2 to 4, wherein
Production method of spherical fine particles. 6. The polysiloxane (B) is represented by the following formula (1-
The method for producing spherical fine particles according to claim 5, which is a polysiloxane represented by any one of (1) and (1-2) or a mixture of both. Embedded image [In the formulas (1-1) and (1-2), Si is a silicon atom, and Ph is a phenyl group. X, Y and Z
Is an independent integer of 1 to 300. ] 7. The mixture (D) contains 0.001 to 10 parts by weight of the reactive silane compound (C) based on 100 parts by weight of the polysiloxane (B).
The method for producing spherical fine particles according to any one of the above. 8. The method according to claim 7, wherein the reactive silane compound (C) is a silane coupling agent. 9. The silane coupling agent represented by the following formula (3-
1) 9. The method according to claim 8, wherein the structure is represented by the following formula. 10. The spherical fine particles according to claim 2, wherein the thermoplastic polycondensate (E) is at least one polyester selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate. Manufacturing method. 11. The method for producing spherical fine particles according to claim 2, wherein the thermoplastic polycondensate (E) is a polyether ester. 12. The method according to claim 2, wherein the thermoplastic polycondensate (E) is a polycarbonate. 13. The temperature T of the mixture (D) immediately before the cooling operation
h1 or Th2 is represented by the following formula (B-1) or (B-2)
And the temperature (Tq1 or Tq2) of the mixture (D) after cooling satisfies the following formula (C-1) or (C-2). Manufacturing method. Tm ≦ Th1 ≦ Tm + 50 (B-1) Tp−50 ≦ Th2 ≦ Tp + 50 (B-2) Tm−100 ≦ Tq1 ≦ Tm (C-1) Tp−100 ≦ Tq2 ≦ Tp (C-2) [In the formulas (B-1) and (C-1), Tm is the melting point of the obtained thermoplastic polycondensate (E), and is represented by the formula (B-2) And in the formula (C-2), Tp has a viscosity of 10 obtained by measuring the thermoplastic polycondensate (E) obtained using a Koka type flow tester at a pressure of 3.9 MPa and a nozzle of 1 mmφ × 10 mmL.
000 poise. All units are in ° C.
It is. The formulas (B-1) and (C-1) are used when the thermoplastic polycondensate (E) is crystalline having a melting point, and the formulas (B-2) and (C-2) are used. Is used when the thermoplastic polycondensate (E) is amorphous without a melting point. ]