JP2006232878A - Fine powder composed of polytrimethylene terephthalate composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fine powder that is useful for an application such as a raw material of various coatings including a powder coating, a raw material for an abrasion material, a finely dispersing agent for preparing various compounds or a lubricant, is excellent in weather resistance, chemical resistance and heat resistance, has appropriate hardness/flexibility and an appropriate melting point, and can be manufactured with good productivity at a low cost without using expensive and complicated equipment, and to provide a manufacturing method of the fine powder. <P>SOLUTION: The powder is composed of a polytrimethylene terephthalate composition and has an average particle size of 0.1-500 μm. The powder is manufactured by grinding the polytrimethylene terephthalate composition previously subjected to a heat treatment at 60-230°C for 0.01-300 hr. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fine powder comprising a polytrimethylene terephthalate composition, and more specifically, various paints that can be produced industrially, have a small particle size, and include abrasives and powder paints. And a fine powder comprising a polytrimethylene terephthalate composition suitable for these additives and a method for producing the same.

  Polytrimethylene terephthalate (hereinafter abbreviated as “PTT”) is a kind of thermoplastic resin, with properties similar to nylon fibers such as soft texture, excellent elastic recovery and easy dyeing, wash and wear properties, and dimensions. It has attracted attention as a revolutionary fiber material having properties similar to polyethylene terephthalate (hereinafter abbreviated as “PET”) fibers such as stability and yellowing resistance. Further, by utilizing characteristics not found in nylon such as low moisture absorption and yellowing resistance, and characteristics not found in polybutylene terephthalate (hereinafter abbreviated as “PBT”) such as easy moldability, extrusion molded articles such as injection molded articles and films, It is expected to be an excellent material as a thermoplastic powder.

Among these, conventionally known thermoplastic powders are made of polyethylene (hereinafter abbreviated as “PE”), nylon, fluorine resin, and the like. However, these resins can be used only for limited applications because of their low hardness, heat resistance, and weather resistance that are not necessarily good. Moreover, it is difficult to obtain fine powder, and even if it can be compared, special equipment and a long production time are required, and it cannot be obtained with high productivity.
On the other hand, PTT can be expected to be a powder having excellent weather resistance, chemical resistance, heat resistance, moderate hardness / flexibility, and melting point than the characteristics of fibers and molded articles. By taking advantage of these features, it is conceivable to expand into applications such as powder coating materials, various coating materials, abrasive materials, fine dispersants and lubricants for various compounds.

In order to be used for these applications, it is necessary that the powder has a small average particle size and can be produced stably industrially. However, since PTT has appropriate hardness and flexibility as described above, these characteristics are features when used as a powder, but it is difficult to produce a fine powder by grinding. It becomes the fault that it is.
As a technique for obtaining PTT powder, there is a proposal of PTT particles having a size of 1 mm obtained by pulverizing polymerization pellets with a sample mill (see, for example, Patent Document 1). In this proposal, the transesterification product is atomized with nitrogen to form particles, and then converted into a solid state in a vacuum, and then heated and polymerized to obtain 0.3 mm PTT particles.

As another technique, a technique of utilizing powder as a starting material for solid-phase polymerization has been proposed (see, for example, Patent Documents 2 and 3). Among these, PTT particles having an average diameter of 0.5 to 20 mm manufactured by pastilation have been proposed.
However, according to the study by the present inventors, any of these techniques can only obtain a powder having a large average particle diameter of 300 μm or more. Furthermore, there is no description or suggestion of a method for reducing the particle size. For this reason, the fine powder which can be manufactured industrially using this technique cannot be obtained.
As a technology for pulverizing a resin with a low glass transition point, such as saturated polyester, into a fine powder, mechanical pulverization while cooling with liquid nitrogen, etc., or adding a poor solvent to a solution in which the resin is dissolved in a good solvent There has also been proposed a technique for producing powder by precipitation, so-called chemical pulverization (see, for example, Patent Document 5). Although it becomes possible to produce a PET powder by using this technique, it is still difficult to produce a fine powder having an average particle size of 200 μm or less. In addition, complicated equipment for using liquid nitrogen or a solvent is required, or a process is added, resulting in a considerably long working time, resulting in extremely deteriorated productivity. The proposal also proposes a technique of pulverizing coarse pellets having a crystallinity of 35% or more obtained by heat-treating a resin mainly composed of PET at 170 ° C. for 6 to 17 hours.

Further, as a fine powder technology of PET, for powder coating, it is composed of PET having a specific size within a specific range of spherical particles having a particle size of 150 μm or less and a ratio of major axis to minor axis of 3 or less. There is a proposal of powder (for example, refer to Patent Document 4). In this proposal, copolymerized PET is treated at 200 to 210 ° C. for 2 to 8 hours, and then pulverized with a hammer type pulverizer to obtain a powder.
However, according to the study by the present inventors, the crystallinity that can improve the pulverizability, the conditions for achieving the crystallinity, and the temperature suitable for the pulverization differ depending on the components of the resin. Even if the technology of copolymerized PET is applied to PTT as it is, the intended fine powder that can be produced industrially cannot be obtained.
Thus, with the conventional techniques, it is not possible to obtain a powder made of a fine PTT composition that can be produced industrially.

International Publication No. 2003/342356 Pamphlet International Publication No. 96/22179 Pamphlet International Publication No. 97/23543 Pamphlet JP 50-159541 A No. 2000-53892

  An object of the present invention is to provide a fine powder which is made of a PTT composition which is a thermoplastic resin and can be industrially produced, and a method for producing the fine powder.

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be achieved, and have made the present invention.
That is, the present invention is as follows.
(1) A powder made of a PTT composition having an average particle size of 0.1 to 500 μm.
(2) The powder according to (1), wherein the average particle size is 1 to 250 μm.
(3) The powder according to (1) or (2), wherein the proportion of PTT is 30% by weight or more.
(4) The powder according to any one of (1) to (3), wherein the crystallinity Xc is 10 to 100%.
Here, the crystallinity Xc is as follows.
Xc = {ρc × (ρs−ρa)} / {ρs × (ρc−ρa)} × 100 (%)
ρa: Amorphous density = 1.305 g / cm ³
ρc: Crystal density = 1.431 g / cm ³
ρs: density of the pellet (g / cm ³ )

(5) The powder according to any one of (1) to (4), wherein the crystallite size is 1-17.5 nm.
Here, the crystallite size is a value calculated from a diffraction peak derived from the (010) plane observed near 2θ = 15.5 ° when the pellet is evaluated by wide-angle X-ray diffraction.
(6) The powder according to any one of (1) to (5), wherein the intrinsic viscosity of PTT is 0.5 to 4 dl / g.
(7) The method for producing a powder according to any one of (1) to (6), wherein the PTT composition that has been heat-treated at a temperature of 60 to 230 ° C. for 0.01 to 300 hours is pulverized.
(8) The method for producing a powder according to (7), wherein mechanical grinding is performed at a temperature of -40 to 100 ° C.
(9) The method for producing a powder according to (7) or (8), wherein the heat treatment temperature is 180 to 225 ° C. and the heat treatment time is 0.1 to 100 hours.
(10) The method for producing a powder according to any one of (7) to (9), wherein the PTT composition to be ground has a crystallinity of 10 to 100%.
(11) The method for producing a powder according to any one of (7) to (10), wherein a PTT composition having an intrinsic viscosity of 0.5 to 4.0 dl / g is pulverized.
(12) Abrasive material containing the powder according to (1) to (6) (13) Abrasive material containing 10 to 100% by weight of the powder according to (1) to (6) (14) (1) to Abrasive material (50) containing the powder according to (6) (15) Paints (16) containing the powder according to (1) to (6) (16) (1) to (6) Containing powder paint

  The powder of the present invention has a small particle size, excellent weather resistance, chemical resistance, heat resistance, moderate hardness / flexibility, melting point, and productivity without using expensive and complicated equipment. It is a fine powder that can be manufactured at low cost. For this reason, it is useful for various applications such as raw materials for various paints such as powder paints, raw materials for abrasives, fine dispersants and lubricants for various compounds.

The present invention will be specifically described below.
The powder of the present invention is a fine powder made of a PTT composition. It is a powder having a small particle size, excellent weather resistance, chemical resistance, heat resistance, moderate hardness / flexibility, melting point, and high temperature and complexity, which is the object of the present invention by comprising a PTT composition. It becomes easy to obtain a powder that can be manufactured at low cost with good productivity without using equipment. This is probably due to the chemical stability and crystallinity that come from the molecular structure of PTT, which is a kind of saturated polyester with low chemical reactivity, and the shock absorption that comes from the zigzag molecular skeleton structure. . Second, it becomes prominent particularly when heat-treated at a high temperature, but it seems that PTT is easily crystallized and easily cracks when crystallized to a certain degree or more.
The PTT composition of the present invention includes cases in which various organic substances and inorganic substances are included in addition to PTT.

  Here, PTT is a polyester having terephthalic acid as an acid component and trimethylene glycol (also referred to as 1,3-propanediol, hereinafter abbreviated as “TMG”) as a diol component. The PTT includes a case where 0 to 50% by weight of other components are copolymerized as long as the effects of the present invention are not impaired. Examples of such copolymer components include 5-sodium sulfoisophthalic acid, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentamethylene glycol, 1,6-hexamethylene glycol, Heptamethylene glycol, octamethylene glycol, decamethylene glycol, dodecamethylene glycol, 1,4-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, oxalic acid, malon Acid, succinic acid, glutaric acid, adipic acid, heptanedioic acid, octanedioic acid, sebacic acid, dodecanedioic acid, 2-methylglutaric acid, 2-methyladipic acid, fumaric acid, maleic acid, itaconic acid, 1,4 -Cyclohexanedicarboxylic acid, 1 3-cyclohexane dicarboxylic acid, ester-forming monomers or polyethylene glycol such as 1,2-cyclohexanedicarboxylic acid, polypropylene glycol, polytetramethylene glycol and copolymers thereof, and the like. The other copolymer component is preferably 30% by weight or less, more preferably 20% by weight or less in consideration of grindability and thermal / mechanical characteristics of the powder.

The polymerization degree of PTT is preferably in the range of 0.5 to 4 dl / g with the intrinsic viscosity [η] as an index. By setting the intrinsic viscosity to 0.5 dl / g or more, a powder having excellent strength and appropriate hardness and flexibility can be obtained. On the other hand, by setting it to 4.0 dl / g or less, it becomes easy to improve the grindability and obtain a powder having a small particle diameter. The intrinsic viscosity [η] is more preferably in the range of 0.6 to 3 dl / g, and still more preferably in the range of 0.7 to 2 dl / g.
The PTT of the present invention has a carboxyl end group concentration of 0 to 100 eq / ton, a cyclic dimer content of 0 to 3% by weight, a bis (3-hydroxypropyl) ether component (structural formula: The content of —OCH ₂ CH ₂ CH ₂ OCH ₂ CH ₂ CH ₂ O— (hereinafter abbreviated as “BPE”) is preferably 0 to 2% by weight. By doing in this way, the weather resistance, chemical resistance, hydrolysis resistance, and heat resistance of the powder can be enhanced.
Here, the cyclic dimer is a dimer in which two trimethylene terephthalate units represented by the following structural formula are connected in a ring.

OC- ◎ -COOGO
｜ ｜
OGOOC- ◎ -CO
Where ◎: benzene ring
G: —CH ₂ CH ₂ CH ₂ —

The carboxyl end group concentration is more preferably 0 to 80 eq / ton or less, further preferably 0 to 50 eq / ton or less, particularly preferably 0 to 30 meq / kg, and the lower the better. The cyclic dimer is more preferably 0 to 2.5% by weight, and further preferably 0 to 2.0% by weight. Moreover, it is preferable that BPE is 0.1 to 1.5 weight%, and it is more preferable that it is 0.15 to 1.2 weight%.
Examples of organic substances other than PTT include cyclic and linear PTT oligomers, monomers of acid components and glycol components constituting PTT, resins other than PTT, and various additives. Examples of resins other than PTT include thermoplastic polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, thermosetting polyesters, thermoplastic polyamides such as nylon 6, nylon 66, nylon 11, and nylon 12, polyethylene, polypropylene, and the like. Polyolefin, polyurethane, fluorine-based polymer, silicon-based polymer, polyphenylene sulfite, epoxy resin, acrylic resin, cellulose resin, and copolymer resins thereof. It is also a preferable example that such a resin is obtained by once collecting a product formed into a fiber, a film, a bottle or the like.

Inorganic substances other than PTT include inorganic fillers such as glass fiber, carbon fiber, talc, mica, wollastonite, kaolin clay, calcium carbonate, titanium dioxide, and gloss and smoothness including silica dioxide. And surface polymerization agents, polymerization catalyst residues, and the like.
Other additives include organic and inorganic dyes and pigments, matting agents, heat stabilizers, flame retardants, antistatic agents, antifoaming agents, color stabilizers, antioxidants, ultraviolet absorbers, crystal nuclei Agents, brighteners, impurity scavengers, surface conditioners and the like.

  As the heat stabilizer, a pentavalent or / and trivalent phosphorus compound or a hindered phenol compound is preferable. The addition amount of the phosphorus compound is preferably 2 to 500 ppm, more preferably 10 to 200 ppm as the weight ratio of the phosphorus element in the powder. Specific examples of the preferred compound include trimethyl phosphite, phosphoric acid, phosphorous acid, and tris (2,4-di-tert-butylphenyl) phosphite (such as Irgafos 168 manufactured by Ciba Specialty Chemicals). A hindered phenolic compound is a phenolic derivative having a substituent having a steric hindrance at a position adjacent to a phenolic hydroxyl group and having one or more ester bonds in the molecule. Is preferably 0.001 to 1% by weight, and more preferably 0.01 to 0.2% by weight, based on the powder.Specific compounds include pentaerythritol-tetrakis [ 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] Such as Irganox 1010 manufactured by Ciba Specialty Chemicals Co., Ltd.), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, octadecyl-3- (3,5-di) -Tert-butyl-4-hydroxyphenyl) propionate (such as Irganox 1076 manufactured by Ciba Specialty Chemicals), N, N'-hexamethylenebis (3,5-tert-butyl-4-hydroxy-hydrocine Namamide), ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate] (such as Irganox 245 manufactured by Ciba Specialty Chemicals), N, N 'Hexane-1,6-diylbis [3- (3,5di-tert- Such as chill-4-hydroxy-phenylpropionic Ona bromide) such as Irganox1098 manufactured (Ciba Specialty Chemicals Corp.) is preferred. It is also one of the preferred methods of course a combination of these stabilizers.

  In the present invention, it is also one of preferable methods to add a scavenger for low molecular weight volatile impurities. The scavenger is preferably a polyamide or polyesteramide polymer or oligomer, or a low molecular weight compound having an amide group or an amine group. The addition amount is preferably 0.001 to 1% by weight, more preferably 0.01 to 0.2% by weight as a weight ratio to the powder. Specific compounds include polyamides such as nylon 6.6, nylon 6 and nylon 4.6, polymers such as polyethyleneimine, and a reaction product of N-phenylbenzeneamine and 2,4,4-trimethylpentene ( Such as Irganox 5057 manufactured by Ciba Specialty Chemicals Co., Ltd.), N, N′hexane-1,6-diylbis [3- (3,5 di-tert-butyl-4-hydroxyphenylpropionamide) (Ciba Irganox 1098 manufactured by Specialty Chemicals Co., Ltd.), 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol (Ciba)・ Irganox 565 manufactured by Specialty Chemicals Co., Ltd.) is preferable. Of course, a combination of these is also a preferred method.

In the present invention, the case where these components react with PTT and the case where they are simply mixed together, and also when they form one particle together with PTT, they are mixed as separate particles to form a powder. Includes cases where the body is formed.
The powder of the present invention has a small particle size and a PTT content of 30% by weight or more in order to obtain a powder having excellent weather resistance, chemical resistance, heat resistance, appropriate hardness / flexibility, and melting point. It is preferably 40% by weight or more, more preferably 50% by weight or more. Here, the ratio of PTT can be determined by analysis using a ¹ H nuclear magnetic resonance spectrum (hereinafter abbreviated as “NMR”) using HFIP: CDCl ₃ = 1: 1 as a solvent. At this time, various PTT oligomers such as cyclic dimers and BPE are included in the PTT ratio.

  The powder of the present invention preferably has an average particle size of 0.1 to 500 μm. By setting the average particle size to 0.1 μm or more, handling such as transfer of powder becomes easy. In addition, when it is 500 μm or less, it becomes easy to obtain a smooth and beautiful coating film when it is used as a powder paint or paint additive, and it is easy to produce a smooth and beautiful polishing surface when it is used as an abrasive. It becomes. The average particle size is more preferably 0.5 to 400 μm, further preferably 1 to 250 μm, and particularly preferably 5 to 100 μm. In addition, in order to obtain a beautiful coating film as a powder coating material or to have good handling properties, particles having a particle size of 1 to 250 μm should be 95% by weight or more of the total particles contained in the powder. Is preferred.

The shape of the powder is difficult to agglomerate in pipes, etc., and can be easily transferred.When powder coating is used, it is easy to apply uniformly to the coating surface or to be easy to use as an abrasive. A shape close to a cube with few whiskers and film-like projections is preferred.
From the viewpoint of ease of handling, the repose angle of the powder is preferably 50 degrees or less, more preferably 42 degrees or less, still more preferably 40 degrees or less, and particularly preferably 38 degrees or less.
The powder of the present invention preferably has a crystallinity (Xc) of 10 to 100% and a crystal size of 1 to 17.5 nm.
Here, the degree of crystallinity is “crystal elastic modulus of PTT”: Katsuhiko Nakamae, Material, Vol. 35, No. 396, page 1067, 1986, published in the paper published in 1986. ) Is transformed from the equation (2), the crystal density value (1.431 g / cm ³ ), and the amorphous density value (1.305 g / cm ³ ) obtained by our experiments.

1 / [rho] _s = {Xc / [rho] _c } + {(1-Xc) / [rho] _a } (1)
Xc = {ρ _c × (ρ _s −ρ _a )} / {ρ _s × (ρ _c −ρ _a )} × 100 (%)
... Formula (2)
ρ _a : Amorphous density = 1.305 g / cm ³
ρ _c : crystal density = 1.431 g / cm ³
ρ _s : density of the pellet (g / cm ³ )
In addition, when components other than PTT are included, the crystallinity degree of PTT is calculated | required from the density and content rate of this component, and said formula.

On the other hand, the crystal size can be obtained by calculating from the diffraction peak derived from the (010) plane observed near 2θ = 15.5 ° when the powder is evaluated by wide-angle X-ray diffraction.
The degree of crystallinity is preferably 20 to 70%, more preferably 30 to 60%. On the other hand, the crystallite size is more preferably 3 to 17 nm, and particularly preferably 5 to 16 nm.
It becomes easy to set it as the outstanding weather resistance, chemical-resistance, heat resistance, moderate hardness and a softness | flexibility by setting it as such crystallinity degree and crystal | crystallization size.
Next, the manufacturing method of the powder of this invention is demonstrated.
The powder of the present invention was formed by extruding a PTT composition obtained by polymerization, or a PTT composition obtained by adding various additives to a PTT composition obtained by polymerization into water in the form of a strand, cooling, solidifying and cutting. It can be obtained by pulverizing after making it into a solid such as a pellet.

The PTT composition can be obtained by a conventionally known polymerization method. For example, dimethyl terephthalate and trimethylene glycol, and if necessary, other copolymer components were used as raw materials, and transesterification was performed at a normal pressure and a temperature of 180 to 260 ° C. using titanium tetrabutoxide as a catalyst by a conventional method. Then, it can obtain by performing a polycondensation reaction at 220-270 degreeC under pressure reduction.
Additives necessary as a powder can be added by a method of adding at the time of polymerization, a method of adding by melt-kneading after polymerization, or a method of combining these, and the kind and amount of the additive are required. It can be selected as appropriate depending on the performance to be achieved. Additives include components that melt by heat, including resins other than PTT, components that do not melt by heat, such as high-melting or non-melting resins, inorganic and organic fillers, pigments, heat stabilizers, and the like. .

When various additives are added by melt-kneading, the PTT composition obtained by polymerization is cooled and solidified, or it is put together with various additives into a uniaxial or biaxial extruder in a molten state. Can be done.
The PTT composition thus obtained is solid or extruded in water in a strand or sheet form, and is solidified and cut, especially in the form of pellets. Is preferable in order to facilitate. In the case of pellets, it is preferable that the average weight per grain is 1-1000 mg because handling properties such as transportation, storage, and pulverization are improved. The weight of one grain is more preferably 5 to 100 mg, further preferably 10 to 70 mg, and particularly preferably 20 to 40 mg. The shape of the pellet may be any of a sphere, a rectangular parallelepiped, a cylinder, and a cone, but when considering the handleability, the length of the longest part is preferably 15 mm or less, more preferably 10 mm or less, and 5 mm or less. More preferably.

Note that the intrinsic viscosity, carboxyl end group concentration, cyclic dimer, and BPE content of the PTT composition used for pulverization do not change greatly even when heat treatment and pulverization steps are performed. Is desirable.
Examples of the method of pulverizing the PTT composition include mechanical pulverization and chemical pulverization, but a method of mechanical pulverization at a temperature near room temperature is preferable because no special solvent or equipment is required and productivity is good.
Here, the vicinity of normal temperature means a case where equipment for controlling the temperature of the pulverizer is not provided, and a case where equipment or solid matter is cooled using cold air or a refrigerant of −40 to 20 ° C. It is not included in the case of so-called freeze pulverization, in which the material is immersed in a refrigerant or the like. In such mechanical pulverization, the temperature of the pulverizer rises due to frictional heat, but is preferably 150 ° C. or lower, more preferably 120 ° C. or lower, and still more preferably 100 ° C. or lower. As described at the beginning, unlike PET and nylon, which are generally used, it is possible to pulverize with good productivity by mechanical pulverization at room temperature as described above because of the use of PTT, which is one of the features of the present invention. It is.

As equipment for pulverization, a known pulverizer can be used. For example, impact type fine grinding machines such as Hosokawa Micron Co., Ltd. ACM Pulperizer, Turbo Industry Co., Ltd. turbo mill, Nisshin Engineering Co., Ltd. blade mill, and Seisin Enterprise Co., Ltd. jet mill etc. In the present invention, an impact type fine pulverizer that performs pulverization with a shearing force is preferable because the productivity can be increased.
When mechanically pulverizing PTT solids such as pellets, the crystallinity is preferably 10% or more, more preferably 20% or more, still more preferably 30% or more, and particularly preferably 40% or more. Is good. By doing so, it becomes easy to obtain a fine powder at a high yield, and it is also easy to reduce the whiskers of the powder particles.

Such crystallinity can be achieved by heat treating the pellet. The heat treatment of the solid material such as pellets is preferably performed at a temperature of 60 to 230 ° C. for 0.01 hour or more. The temperature of the heat treatment is preferably not more than the temperature at which the solid material is fused, and the time may be long, but in practice it is preferably not more than 300 hours.
In order to further improve the grindability, the temperature of the heat treatment is more preferably 150 to 230 ° C, further preferably 180 to 225 ° C, and particularly preferably 200 to 220 ° C. The heat treatment time is more preferably 0.1 to 100 hours, further preferably 0.2 to 50 hours, and particularly preferably 0.3 to 30 hours. The heat treatment is more preferably performed in an inert gas atmosphere such as nitrogen or carbon dioxide gas in order to suppress coloring of PTT by oxygen.

It is preferable that the pulverized solid is subsequently classified and filtered. By removing coarse particles and fine particles by classification and filtration, handling such as transfer of powder becomes easy, and a smooth and beautiful coating film can be obtained when used as a powder paint or paint additive. It becomes easy, and it becomes easy to give a smooth and beautiful polished surface when used as an abrasive. Such classification and filtration can be performed using a vibration sieve or an air classifier.
The powder thus obtained can be further mixed with other powder using a Henschel mixer or the like. Examples of powders to be mixed include PTT powders containing different additives, and powders made of resins other than PTT, organic substances, and inorganic substances. When mixing the powder in this step, it is preferable to appropriately adjust the size of the powder according to the specific gravity difference or amount.

The fine powder comprising the PTT composition of the present invention is useful for various applications such as raw materials for various paints such as powder paints, raw materials for abrasives, fine dispersants and lubricants for various compounds.
As a powder coating material and its raw material, it is preferable to use a powder having an average particle diameter of 10 to 500 μm obtained by pulverizing a PTT composition obtained by melt-kneading a pigment and a heat stabilizer as required. By doing so, it can be used as a thermoplastic powder coating suitable for the fluid dipping method, electrostatic coating method, etc., and can perform coating with excellent surface protection performance, appearance, and flexibility of the coating film. it can. The average particle size of the PTT powder of the present invention is preferably 50 to 250 μm, and more preferably 80 to 150 μm when used in the fluidized immersion method. On the other hand, when used in the electrostatic coating method, the average particle size is more preferably 10 to 150 μm, and still more preferably 20 to 80 μm.

Moreover, the powder of the present invention can be used as a raw material for a solvent paint or a thermosetting powder paint base material, an additive for the purpose of imparting flexibility, a matte appearance, or the like. In this case, the average particle size is preferably 0.1 to 50 μm, more preferably 1 to 30 μm, and still more preferably 5 to 20 μm. By doing so, it becomes easy to obtain a coating material having a smooth coating surface and excellent cosmetics. Of course, it can also be used as an additive for imparting an uneven shape to the surface. In this case, it is necessary to appropriately select the average particle size according to the requirements.
The PTT powder of the present invention is also useful as an abrasive and its raw material.
As an abrasive, it can be used for any of a dry type using powder as it is, a wet type used in a slurry form with a liquid such as water, a solid type used by being solidified with a resin or adhering to a fiber, etc. The powder of the present invention is suitable for dry and wet, particularly dry abrasives.

  In the dry process, the surface of the material is ground and processed with a method of projecting powder with compressed air (air blasting method) or a method of spraying the workpiece at high speed with a blade that rotates at high speed with the power of a motor (shot blasting method). Used for peening, deburring, cleaning, engraving, etc. The PTT powder has an appropriate hardness and heat resistance capable of satisfying both a high polishing power required for an abrasive and not damaging a product or an apparatus. Further, the PTT powder of the present invention has characteristics that it can be easily pulverized and does not change in size or shape even when used repeatedly as an abrasive. Although the reason is not clear, it is considered that the PTT powder is easily pulverized by a large shear force applied during pulverization, but is strong against an impact force applied when used as an abrasive. As a result, it is possible to exhibit characteristics that the durability is high and the substance to be processed is not contaminated. Furthermore, since the specific gravity of PTT powder is larger than that of other abrasive resins such as nylon and polycarbonate, excellent polishing performance can also be exhibited.

There are various types of abrasives, and the most suitable abrasive is selected depending on the workpiece. The PTT powder of the present invention takes advantage of the above-mentioned features to deburr resin molded products, metal die cast products, metals and resins. It can be used for various purposes such as cleaning of molded products and removal of dirt.
In the wet process, it is often used in the form of a slurry mixed with water, various organic solvents, surfactants, etc., but the PTT powder of the present invention has high chemical resistance and little change in properties due to hygroscopicity and moisture absorption. So it can be used mixed with various substances.
When used as such an abrasive and its raw materials, the polishing power and durability suitable for the purpose can be obtained by adding PTT powder alone, adding organic or inorganic fillers, or mixing with other powders. It can be set as the abrasive | polishing material with these.
The particle size of the powder is also appropriately selected according to the purpose, but the average particle size is preferably 1 to 500 μm, more preferably 10 to 250 μm, and still more preferably 30 to 150 μm from the viewpoint of ease of handling. The shape is preferably a shape close to a sphere or a cube and has few whiskers and film-like projections.

The present invention will be described based on examples.
The main measurement values in the examples were measured by the following methods.
(1) PTT content rate, cyclic dimer content rate, BPE content rate PTT content rate (% by weight) is obtained by dissolving 100 mg of paint or coating film in HFIP: CDCl3 = 1: 1, and insoluble components as MEMBRANE FILTER (1 μm). , PTFE), and the solution after filtration was determined by 1H-NMR measurement. As a measuring machine, FT-NMR DPX-400 (manufactured by Bruker) was used. Moreover, the insoluble component removed by filtration was used for measuring the weight after vacuum drying and determining the PTT content.

(2) Intrinsic viscosity [η]
The intrinsic viscosity [η] is extrapolated to a zero concentration by using the Ostwald viscometer, and the ratio ηsp / C of the specific viscosity ηsp and the concentration C (g / 100 ml) in o-chlorophenol at 35 ° C. Sought according to.
[Η] = lim (ηsp / C)
C → 0
(3) Concentration of carboxyl end group 1 g of PTT composition was dissolved in 25 ml of benzyl alcohol, and then 25 ml of chloroform was added, followed by titration with a 1/50 N potassium hydroxide benzyl alcohol solution to obtain a titration value VA (ml). It calculated | required according to the following formula | equation from the blank value V0 when there is no PTT composition.
Carboxyl end group concentration (eq / ton) = (VA−V0) × 20

(4) Particle size (average particle size, particle size distribution)
The particle size (average particle size, particle size distribution) of the powder dispersed in water was measured using a Microtrac FRA particle size analyzer manufactured by Nikkiso Co., Ltd. using a laser light diffraction / scattering method.
(5) Shape The shape of the powder particles was observed with an optical microscope.
(6) Angle of repose Measurement was performed according to JIS R9301.
(7) Crystallinity It calculated | required according to the following formula from the density calculated | required with the density gradient tube method using the density gradient tube created with carbon tetrachloride and n-heptane based on JIS-L-1013.
Xc = {ρ _c × (ρ _s −ρ _a )} / {ρ _s × (ρ _c −ρ _a )} × 100 (%)
ρ _a : Amorphous density (g / cm ³ ) = 1.300 g / cm ³
ρ _c : Crystal density (g / cm ³ ) = 1.431 g / cm ³
ρ _s : density of the pellet (g / cm ³ )

(8) Crystal size The crystal size was determined by wide-angle X-ray diffraction under the following conditions.
Measuring device: Rotorflex RU-200, manufactured by Rigaku Corporation Measuring method: reflection method X-ray intensity: 40 kv, 120 mA
X-ray source: CuKα ray Slit spacing: DS = 0.6, RS = 0.3, SS = 1
Microcrystal size: The crystallite size was determined from the half width of the diffraction peak determined by the peak separation method using the following formula.
Microcrystal size (nm) = Kλ / (β × cos θ)
K: Constant (= 1)
λ: X-ray wavelength (= 0.154 nm)
β: half width of peak (°)
θ: Value obtained from the angle (2θ) at which diffraction is observed (°)

[Example 1]
Intrinsic viscosity [η] is 1.0 dl / g, carboxyl end group concentration is 15 eq / ton, BPE content is 0.5% by weight, the average weight of one grain is 25 mg, and the length of the longest part is A 3 mm cylindrical pellet was heat-treated at 120 ° C. for 2 hours in a box-type hot air dryer to obtain a heat-treated pellet having a crystallinity of 25% and a crystal size of 12 nm.
The obtained heat-treated pellets were pulverized and classified using a combination of “Turbo Mill”, a mechanical pulverizer manufactured by Turbo Industry Co., Ltd., and a 100-mesh vibrating screen to obtain powder. In the pulverizer, the pulverized pellets were classified by a 100-mesh vibrating screen, and those that passed through the sieve were made into products, and those that did not pass were returned to the pulverizer and pulverized again.
Table 1 shows the main production conditions and powder characteristics. Since the crystallinity and crystal size of the pellet and the powder are the same, only the powder will be described. The same applies to other examples and comparative examples.

The obtained powder has a PTT content of 99% or more, and the pulverization amount per hour is as high as 10 kg, so that the pulverization is good, the average particle size is 140 μm, and there are only a few whiskers, The angle of repose was 45 degrees, and it was an excellent powder with good fluidity.
The obtained powder was used alone for deburring attached to the lead frame of a semiconductor element molded with an epoxy resin. At this time, the powder was projected by an air blast method using compressed air. As a result, only the burrs adhering to the lead frame could be removed without damaging the semiconductor element itself molded with resin. Also, almost no dust was generated and the device was hardly soiled. The used powder was repeatedly used 5 times, but there was almost no change in the deburring performance and the contamination status of the device, and the durability was excellent.

[Examples 2 to 4]
A powder was obtained in the same manner as in Example 1 except that the conditions described in Table 1 were changed. Table 1 shows the main production conditions and powder characteristics.
In Example 2, when a 50-mesh sieve was used, although the particle size increased, the amount of pulverization per hour increased, and a powder with good fluidity pulverizability was obtained as can be seen from the low angle of repose. It was.
In Example 3, after drying at 120 ° C. for 2 hours, heat treatment was performed at 210 ° C. for 0.5 hours while flowing nitrogen at a rate of 1 liter / min using a rotary metal flask having an internal volume of 5 liters and an oil bath. When a heat-treated pellet having a crystallinity of 45% and a crystal size of 15 nm was used, a good powder with excellent pulverization, small average particle size, and excellent fluidity was obtained. .
In Example 4, when pellets composed of a PTT composition having an intrinsic viscosity of 0.6 dl / g and a low degree of polymerization were used for pulverization, the pulverization property was further improved, the average particle size was small, and the fluidity was excellent. A good powder was obtained.

[Example 5]
The average weight of one grain made of a PTT composition having an intrinsic viscosity [η] of 1.15 dl / g obtained by performing a heat treatment at 200 ° C. for 20 hours in combination with solid-phase polymerization is 25 mg, and the length of the longest part Was obtained in the same manner as in Example 1 except that pellets having a columnar shape of 3 mm and a high crystallinity of 48% were used for pulverization. Table 1 shows the main production conditions and powder characteristics.
The obtained powder was excellent in grindability, fine particles with an average particle diameter of 80 μm, no whiskers, an angle of repose of 37 degrees, and good fluidity.
Using the obtained powder alone, the mold surface used for injection molding of polybutylene terephthalate resin was cleaned. At this time, the powder was projected by an air blast method using compressed air. As a result, it was possible to cleanly remove only the resin dirt adhering to the surface without damaging the mold body. Moreover, almost no dust was generated and the mold was hardly soiled. The used powder was repeatedly used 3 times, but there was almost no change in the cleaning performance and the contamination status of the mold, and the durability was excellent.

[Example 6]
A powder was obtained in the same manner as in Example 5 except that a blade mill manufactured by Nissin Engineering Co., Ltd. was used as the pulverizer. Table 1 shows the main production conditions and powder characteristics.
The obtained powder was very fine with an average particle diameter of 20 μm and had no whiskers.
When the obtained powder was added to an acrylic paint diluted with paint thinner so as to be 5% by weight with respect to the paint component, a paint capable of uniform matte coating without large unevenness was obtained. .

[Example 7]
70 parts by weight of a PTT composition having an intrinsic viscosity [η] of 1.0 dl / g, a carboxyl end group concentration of 15 eq / ton, and a BPE content of 0.6% by weight, and processed titanium I manufactured by Taisei Kagaku Co., Ltd. 30 parts by weight of -131E is put into a twin screw extruder (Toshiba Machine Co., Ltd .: TEM58), screw rotation speed is 300 rpm, cylinder temperature is 240 ° C., extrusion speed is 150 kg / hr (residence time is 1 minute), reduced pressure Melt kneading was performed at a degree of 0.04 MPa. The kneaded polymer was formed into a strand shape, extruded into water, cooled, solidified, and cut to obtain a cylindrical pellet having an average weight of 30 mg and a longest portion of 3 mm in length.
The obtained pellets were heat-treated and pulverized in the same manner as in Example 3 to obtain powder. Table 1 shows the main production conditions and powder characteristics.
The obtained powder was a good powder having excellent grindability, a small average particle diameter and excellent fluidity.

[Example 8]
A powder was obtained in the same manner as in Example 7 except that 70 parts by weight of melted and kneaded wollastonite NYGLOSS8 manufactured by NICO Corporation was used instead of the processed titanium. Table 1 shows the main production conditions and powder characteristics.
The obtained powder was a good powder having excellent grindability, a small average particle diameter and excellent fluidity.

[Examples 9 and 10]
Instead of 100 parts by weight of PTT, in Example 9, 90 parts by weight of PTT used in Example 2, 10 parts by weight of PET having an intrinsic viscosity [η] of 0.6 dl / g and a carboxyl end group concentration of 40 eq / ton, were used in Example 10. Then, 80 parts by weight of PTT used in Example 2 and 20 parts by weight of Iupilon S2000, which is a polycarbonate manufactured by Mitsubishi Engineering Plastics Co., respectively, were used in the same manner as in Example 2 except for the conditions shown in Table 1. Got. Table 1 shows the main production conditions and powder characteristics.
In any case, the obtained powder was a powder having a fine particle size, few whiskers, and good fluidity.

[Example 11]
A copolymer PTT having an intrinsic viscosity of 0.9 dl / g copolymerized with 10% by weight of 1,4-butanediol and a carboxyl end group concentration of 20 eq / ton was used in place of PTT, except for the conditions shown in Table 1. A powder was obtained in the same manner as in Example 2. Table 1 shows the main production conditions and powder characteristics. The obtained powder was a powder having a fine particle size and good fluidity although some whiskers were observed.

[Example 12]
Into 100 parts by weight of a PTT composition having an intrinsic viscosity [η] of 1.0 dl / g, a carboxyl end group concentration of 15 eq / ton, and a BPE content of 0.6% by weight, liquid paraffin manufactured by Matsumura Oil Research Co., Ltd. , Smoyl P-260 was used as an additive, 0.03% by weight, Mitsubishi Carbon Black made by Mitsubishi Chemical Co., Ltd. was used as a black pigment, 0.1% by weight, and Ciba Specialty Chemicals ( 0.1 parts by weight of Irganox 1098 manufactured by Co., Ltd. and 0.1 parts by weight of TINUVIN 234 manufactured by Ciba Specialty Chemicals Co., Ltd. as a UV absorber were dry blended and then twin screw extruder (manufactured by Toshiba Machine Co., Ltd.) : TEM58), screw rotation speed 300rpm, cylinder temperature 240 ° C (polymer temperature near the tip nozzle was 260 ° C), Out rate 150 Kg / hr (1 minute dwell time), were melt-kneaded at a reduced pressure of 0.04 MPa. The kneaded polymer was made into a strand shape and extruded into water, and then cooled, solidified, and cut to obtain solid pellets.

The obtained pellets were heat-treated and pulverized in the same manner as in Example 3 to obtain powder. Table 1 shows the main production conditions and powder characteristics.
The obtained powder was an excellent powder having a fine PTT content of 99% or more, an average particle size of 80 μm, no whiskers, and good fluidity.
Next, the obtained powder was used as a powder coating by a fluidized dipping method. In the fluidized dipping method, a cylindrical shape with a diameter of 200 mm, a PE non-woven fabric is stretched from the bottom so that air flows uniformly in the cross section, and 2 kg is put into a cylindrical container, and the volume of the powder is 1.4 from the bottom. Air was introduced so as to be doubled to create a fluidized immersion layer. A steel plate having a thickness of 3.2 mm, a length of 100 mm, and a width of 40 mm heated to 310 ° C. was immersed in this fluid immersion layer for 2 seconds to melt and adhere the paint, and then taken out and left in the air for 30 seconds. After that, it was put in water and rapidly cooled for painting. The surface of the object to be coated was blasted to give unevenness. The obtained coating film physical properties are shown in Table 1.
By using the obtained powder as a paint, a coating film having no pinholes and having excellent adhesion, impact resistance, hardness and excellent appearance was obtained.

[Comparative Examples 1 and 2]
Instead of PTT, Comparative Example 1 uses 100 parts by weight of PET used in Example 9, and Comparative Example 2 uses 100 parts by weight of polycarbonate used in Example 10, except for the conditions shown in Table 1. 1 to obtain a powder. As shown in Table 1, in either case, the vibrating screen was clogged in about 10 to 30 minutes after the start of pulverization, and the powder could not be produced continuously. When the powder obtained until the eyes were clogged was examined, in all cases, the particle size was large and the powder was full of mustache-like protrusions, and the fluidity was poor.

  The present invention relates to a fine powder comprising a PTT composition. More specifically, the present invention can be produced industrially, has a small particle size, and various paints including abrasives and powder paints, and the like. The present invention provides a fine powder comprising a PTT composition suitable for these additives and a method for producing the same.

Claims (16)

  A powder comprising a polytrimethylene terephthalate composition having an average particle size of 0.1 to 500 µm.   2. The powder according to claim 1, wherein the average particle size is 1 to 250 [mu] m.   The powder according to claim 1 or 2, wherein the proportion of polytrimethylene terephthalate is 30% by weight or more. The powder according to any one of claims 1 to 3, wherein the crystallinity Xc is 10 to 100%.
Here, the crystallinity Xc is as follows.
Xc = {ρc × (ρs−ρa)} / {ρs × (ρc−ρa)} × 100 (%)
ρa: Amorphous density = 1.305 g / cm ³
ρc: Crystal density = 1.431 g / cm ³
ρs: density of the pellet (g / cm ³ ) The powder according to any one of claims 1 to 4, wherein the crystallite size is 1-17.5 nm.
(Here, the crystallite size is a value calculated from a diffraction peak derived from the (010) plane observed around 2θ = 15.5 ° when the pellet is evaluated by wide-angle X-ray diffraction.)   The powder according to any one of claims 1 to 5, wherein the polytrimethylene terephthalate has an intrinsic viscosity of 0.5 to 4 dl / g.   The method for producing a powder according to any one of claims 1 to 6, wherein the polytrimethylene terephthalate composition heat treated for 0.01 to 300 hours in advance at a temperature of 60 to 230 ° C is pulverized.   The method for producing a powder according to claim 7, wherein the powder is mechanically pulverized at a temperature of -40 to 100 ° C.   The method for producing a powder according to claim 7 or 8, wherein the heat treatment temperature is 180 to 225 ° C and the heat treatment time is 0.1 to 100 hours.   The method for producing a powder according to any one of claims 7 to 9, wherein the polytrimethylene terephthalate composition to be pulverized has a crystallinity of 10 to 100%.   The method for producing a powder according to any one of claims 7 to 10, wherein a polytrimethylene terephthalate composition having an intrinsic viscosity of 0.5 to 4.0 dl / g is pulverized.   An abrasive comprising the powder according to claim 1.   An abrasive comprising 10 to 100% by weight of the powder according to claim 1.   An abrasive comprising 50 to 100% by weight of the powder according to claim 1.   A paint comprising the powder according to claim 1.   A powder coating material comprising the powder according to claim 1.