Filler Granules for Engineering Resins

Abstract

To provide a filler granulated substance which can improve supply stability and supply accuracy of a filler when a resin composition is prepared, and can stably obtain a resin composition with high productivity.SOLUTION: A filler granulated substance for an engineering resin includes a filler and a binder, wherein bulk density of the filler is 0.01-1 kg / L, the binder contains a resin having a heating weight reduction initiation temperature of 300°C or higher, and a content ratio of the filler is 80-99.9 pts.wt. with respect to 100 pts.wt. of the total amount of the filler and the binder.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a filler granulate for engineering resins.

Background Art

[0002] Engineering resins have high heat resistance and excellent mechanical strength. For the purpose of imparting various functions, engineering resins are often melt-kneaded and compounded with various fillers for use. Recently, in order to maximize the modification effect of engineering resins by fillers, resin compositions containing more fillers have often been demanded. However, fillers blended in engineering resins are often in powder form. Powder fillers generally have a small bulk specific gravity and poor fluidity during transfer, resulting in handling problems such as transportation, storage, packaging, supply stability to processing machines, etc., and many problems to be solved in terms of working environment and safety for the human body. In addition, when supplying powder fillers to a device (for example, an extruder), a feed neck is likely to occur at the supply port, and the productivity (discharge amount) does not increase, making it difficult to stably obtain a resin composition with a high filler concentration at a high production speed.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The present invention has been made to solve the above problems, and an object thereof is to provide a filler granulate that can be used even at a high melt processing temperature, can improve the supply stability and supply accuracy of the filler when preparing a resin composition containing a high concentration of the filler, and enables obtaining a resin composition excellent in composition stability at a high productivity.

Means for Solving the Problems

[0004] The filler granulate for engineering resins of the present invention contains a filler and a binder, the bulk density of the filler is 0.01 kg / L to 1 kg / L, the binder contains a resin having a starting temperature of weight loss upon heating of 300°C or higher, and the content ratio of the filler is 80 parts by weight to 99.9 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder. In one embodiment, the filler is in powder form. In one embodiment, the binder is composed of at least one selected from the group consisting of urethane resins, epoxy resins, polyester resins, nylon resins, polyamide elastomer resins, and polyvinyl pyrrolidone resins. In one embodiment, the filler granulate further contains a dispersant. In one embodiment, the content ratio of the dispersant is 0.1 part by weight to 15 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder. In one embodiment, the dispersant is at least one selected from the group consisting of polyhydric alcohol fatty acid esters, fatty acid amides, polyglycerin fatty acid esters, condensed hydroxy fatty acids, and alcohol esters of condensed hydroxy fatty acids. According to another aspect of the present invention, there is provided a method for producing the filler granulate. This production method includes a mixing step of mixing the filler and the binder, a granulation step of granulating the mixture obtained through the mixing step to obtain a granulate precursor, and a drying step of drying the granulate precursor. In one embodiment, the granulation step includes granulating by a semi-wet granulation method. In one embodiment, the granulation step includes performing granulation by a disk pelleter method. According to another aspect of the present invention, there is provided the use of the filler granulate as a raw material for melt-kneading with respect to engineering resins. In one embodiment, the engineering resin is at least one selected from the group consisting of polybutylene terephthalate (PBT), polycarbonate (PC), polyacetal (POM), polyamide (PA), modified polyphenylene ether (m-PPE), fluororesin, polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polysulfone (PSU), polyethersulfone (PES), polyarylate (PAR), polyamideimide (PAI), thermoplastic polyimide (TPI), polyetherimide (PEI), polyetheretherketone (PEEK), and liquid crystal polymer (LCP).

Advantages of the Invention

[0005] According to the present invention, it is possible to provide a filler granulate that can improve the supply stability and supply accuracy of a filler when preparing a resin composition, and enables the stable production of a resin composition with high productivity. The filler granulate of the present invention can be particularly preferably used when obtaining a resin composition containing an engineering resin, and can provide a resin composition in which the properties derived from the filler are efficiently imparted without inhibiting the properties derived from the engineering resin.

Embodiments for Carrying Out the Invention

[0006] A. Overview of filler granulates for engineering resins The filler granulate for an engineering resin of the present invention (hereinafter, also simply referred to as a filler granulate) contains a filler and a binder. The filler has a bulk density of 0.01 kg / L to 1 kg / L. Typically, the filler is in powder form. The binder contains a resin A having a heat weight loss start temperature of 300°C or higher. The content ratio of the filler is 80 parts by weight to 99.9 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder.

[0007] The filler granulate of the present invention is used in the production of a filler-containing resin composition and can be added and used during the melt-kneading of the resin composition. Thus, by using the filler granulate of the present invention, a filler-containing resin composition having functions derived from the filler can be obtained. The filler granulate of the present invention has a structure in which the filler is granulated by a binder. By preparing the filler-containing resin composition using the above filler granulate, the composition stability and productivity of the resin composition can be improved. Specifically, since the above filler granulate is extremely excellent in the charging stability to devices such as an extruder, by using the filler granulate, the composition accuracy (composition stability) and productivity (compound processing speed per hour) of the filler-containing resin composition can be dramatically improved. In addition, it can significantly improve the working environment pollution caused by dust, improve the labor safety and health environment of workers, and further greatly shorten the time for equipment switching and cleaning.

[0008] In one embodiment, the filler-containing resin composition includes an engineering resin. In the present invention, by including a binder containing a resin A having a heat weight loss start temperature of 300 °C or higher, a filler granulate that is significantly useful in combination with an engineering resin can be provided. For example, the filler granulate is useful in that it can be used in the processing temperature range of an engineering resin (for example, 300 °C or higher). By appropriately selecting the resin contained in the binder, a filler granulate excellent in affinity (compatibility) with an engineering resin can be obtained, and a filler-containing resin composition in which the characteristics of the engineering resin are preferably exhibited can also be obtained. Furthermore, by using the filler granulate and an engineering resin in combination, a filler-containing resin composition having significantly excellent filler dispersibility can be obtained. In this specification, the "engineering resin" refers to a resin having a deflection temperature under load of 100 °C or higher in accordance with ASTM D648.

[0009] In one embodiment, the filler granulate further contains a dispersant. By adding a dispersant, it is possible to produce with excellent production efficiency while containing a large amount of filler, and to obtain a filler granulate excellent in quality stability (shape stability, uniformity of pellet hardness, and low fine powder contamination). The filler granulate containing a dispersant contains the filler at a high concentration, and the filler-containing resin composition obtained using the filler granulate has excellent filler dispersibility.

[0010] In one embodiment, the filler granulate is produced by a semi-wet granulation method. According to the semi-wet granulation method, the above effects become remarkable.

[0011] The filler granulate can be in any suitable shape. Typically, the filler granulate is cylindrical (pellet-shaped).

[0012] When the filler granulate is cylindrical, the diameter of the filler granulate is, for example, 2 mm to 5 mm. Also, the length (height) of the filler granulate is, for example, 1 mm to 5 mm. With such a shape, it is possible to obtain a filler granulate that can be preferably combined and used with a resin (especially an engineering resin). The diameter of the filler granulate can be adjusted by the diameter of the die hole of the disk plate during granulation, and the length can be adjusted by the distance between the disk plate and the cutter. By matching the filler granulate to the pellet size of the resin (especially an engineering resin) used in combination, the handleability is improved, and the dispersibility of the filler in the melt compound is improved.

[0013] The breaking stress of the filler granulate measured by a wooden hardness tester is preferably 0.05 kg to 10 kg, more preferably 0.5 kg to 7 kg, and even more preferably 1.0 kg to 5 kg. Within such a range, the handleability and filler dispersibility are excellent. Here, the breaking stress indicates the average collapse stress measured for 20 or more particles.

[0014] The water content of the filler granulate can be any appropriate water content. The water content of the filler granulate is preferably 10% by weight or less, more preferably 5% by weight or less, still more preferably 3% by weight or less, particularly preferably 1% by weight or less, and most preferably 0.5% by weight or less.

[0015] The bulk density of the filler granulate can be any appropriate bulk density according to the type of filler. When the filler is a mineral (natural mineral), the bulk density of the filler granulate is preferably 0.5 kg / L to 2.0 kg / L. By increasing the bulk density, the supply rate and supply stability of the filler granulate are enhanced when performing melt kneading with a resin (especially an engineering resin).

[0016] A-1. Filler As described above, the bulk density of the filler is 0.01 kg / L to 1 kg / L. The bulk density of the filler is preferably 0.1 kg / L to 0.8 kg / L, and more preferably 0.2 kg / L to 0.6 kg / L. The bulk density of the filler is calculated by allowing the filler to naturally fall into a liter measure until it is full and then accurately measuring the weight with a volume of exactly 1 liter (unit: kg / L). As described above, in one embodiment, the filler is in powder form. In the filler granulate of the present invention, it is advantageous in terms of improving the supply stability and supply accuracy for the filler (especially the filler with a low bulk density and in powder form), and it is possible to stably obtain a filler-containing resin composition with high productivity. The size of the filler can be any appropriate size. The number average particle diameter of the filler is, for example, 10 nm to 100 μm. The size of the filler can be determined by the laser diffraction method.

[0017] As described above, in the filler granulated product of the present invention, the content ratio of the filler is 80 to 99.9 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder. Within such a range, a filler-containing resin composition having the characteristics derived from the filler efficiently imparted thereto can be obtained. The content ratio of the filler is preferably 82 to 99 parts by weight, more preferably 85 to 98 parts by weight, still more preferably 87 to 97 parts by weight, and even more preferably 90 to 96 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder. In one embodiment, the content ratio of the filler is 90 to 99.9 parts by weight with respect to 100 parts by weight of the filler granulated product.

[0018] The volume content ratio of the filler in the filler granulated product is preferably 40 to 95% by volume, more preferably 50 to 90% by volume, and still more preferably 60 to 85% by volume.

[0019] As the filler, any appropriate filler can be used according to the characteristics required for the filler-containing resin composition and / or the molded article obtained from the filler-containing resin composition.

[0020] Examples of the characteristics and effects that can be imparted by the filler include, for example, weight increase or weight reduction, reinforcement (increase in rigidity, increase in elastic modulus, increase in strength), dimensional stability, molding cycle (crystallization rate), degree of crystallinity, thermal conductivity, electrical conductivity, magnetism, piezoelectricity, vibration damping, sound insulation, slidability, heat insulation, electromagnetic wave absorption, light reflection, light scattering, heat ray radiation, flame retardancy, radiation protection, ultraviolet protection, dehumidification, dehydration, deodorization, gas absorption, gas barrier, anti-blocking, oil absorption, antibacterial property, biodegradation promotion, improvement of bio-degree (improvement of the ratio of components derived from natural products), and the like.

[0021] For example, for the purpose of increasing volume, calcium carbonate, talc, silica, and clay are suitable. For the purpose of reinforcement, wollastonite, potassium titanate, zonnolite, gypsum fiber, aluminum borate, fibrous magnesium compound (MOS), aramid fiber, various fiber systems, carbon fiber (carbon fiber), glass fiber (glass fiber), talc, mica, glass flake, polyoxybenzoyl whisker, etc. are suitable. For the purpose of imparting antibacterial properties, catechin, silver ion-loaded zeolite, copper phthalocyanine, etc. are suitable. For the purpose of imparting gas barrier properties, synthetic mica-based, nano-fillers of clay-synthetic mica, etc. are suitable. For the purpose of weight reduction, balloon systems such as silica balloon, glass balloon, cenosphere, perlite, shirasu balloon, etc. are suitable. For the purpose of imparting conductivity, carbon black, graphite, carbon fiber, metal powder, metal fiber, metal foil, etc. are suitable. For the purpose of imparting magnetism, various magnetic materials, various ferrite systems, magnetic iron oxide, samarium cobalt (Sm-Co), Nd-Fe-B, etc. are suitable. For the purpose of imparting thermal conductivity, alumina, AlN, BN, BeO, etc. are suitable. For the purpose of imparting piezoelectricity, barium titanate, lead zirconate titanate (PZT), etc. are suitable. For the purpose of imparting vibration damping properties, mica, graphite, potassium titanate, zonnolite, carbon fiber, ferrite, etc. are suitable. For the purpose of imparting sound insulation properties, iron powder, lead powder, barium sulfate, etc. are suitable. For the purpose of imparting slidability, graphite, hexagonal BN, molybdenum disulfide, Teflon (registered trademark) powder, talc, high molecular weight polyethylene, etc. are suitable. For the purpose of imparting electromagnetic wave absorption, electromagnetic wave absorption ferrite, graphite, charcoal powder, carbon microcoil (CMC), carbon nanotube (CNT), PZT, etc. are suitable. For the purpose of imparting light reflection and light scattering, titanium oxide, glass beads, calcium carbonate, aluminum powder, mica, etc. are suitable. For the purpose of imparting heat ray radiation, magnesium oxide, hydrotalcite, MOS, alumina, charcoal powder, etc. are suitable. For the purpose of flame retardancy, antimony oxide, aluminum hydroxide, magnesium hydroxide, zinc borate, red phosphorus, zinc carbonate, hydrotalcite, dawsonite, bromine-based flame retardant, phosphorus-based flame retardant, etc. are suitable. For the purpose of radiation protection, lead powder, barium sulfate, etc. are suitable.For the purpose of "UV protection", titanium oxide, zinc oxide, iron oxide, etc. are suitable. For the purpose of dehumidification and dehydration, calcium oxide, magnesium oxide, etc. are suitable. For the purpose of deodorization and gas absorption, zeolite, activated clay, etc. are suitable. For the purpose of antiblocking (preventing film adhesion), silica, calcium carbonate, talc, spherical fine particles (silicone or acrylic beads), etc. are suitable. For the purpose of oil absorption (printing ink absorption, quick drying property, etc.), spherical calcium carbonate, spherical zonotrite, etc. are suitable. For the purpose of water absorption, water-absorbing polymer gel, calcium oxide, magnesium oxide, etc. are suitable. For the purpose of improving biocompatibility, cellulose-based materials (wood powder, wood fiber, sawdust, wood chips, newsprint, paper, linen, hemp, straw, rice husk, kenaf, jute, sisal, peanut shell, soybean hull, etc.), starch, natural rubber, etc. are suitable.

[0022] A-2. Binder In one embodiment, the binder can be composed of any suitable resin. The binder is used to join powdery fillers together to obtain a granulated product having appropriate disintegration stress, and can be a single resin or a combination of multiple resins. Examples of the resin constituting the binder include polyolefin-based resins, polyvinyl alcohol-based resins, polyalkylene glycol-based resins, polyvinyl pyrrolidone-based resins, polyester-based resins, polyamide-based resins, acrylic-based resins, urethane-based resins, epoxy-based resins, etc. In one embodiment, at least one selected from the group consisting of urethane-based resins, epoxy-based resins, polyester-based resins, nylon-based resins, polyamide elastomer-based resins, and polyvinyl pyrrolidone-based resins is preferably used as the resin constituting the binder. These resins exhibit excellent affinity (compatibility) with engineering resins and have heat resistance that can withstand use at high melting processing temperatures. By using such resins, an excellent filler granulated product can be obtained in which a high concentration of fillers can be blended with high dispersion without impairing the properties of the engineering resin.

[0023] As described above, the binder contains a resin A (hereinafter also simply referred to as resin A) having a heat weight loss start temperature of 300°C or higher. The heat weight loss start temperature of resin A is preferably 320°C or higher, more preferably 340°C or higher. The upper limit of the heat weight loss start temperature of resin A is, for example, 400°C. The heat weight loss start temperature is measured using a thermogravimetric balance in a nitrogen atmosphere in the range of room temperature to 400°C at a heating rate of 10°C / min. A temperature-weight plot is taken for the sample (5 to 30 mg) in an aluminum pan, and a baseline (straight line A) is plotted for the flat portion above 100°C after the contained moisture has been released from the sample. Further, a tangent line (straight line B) that becomes the maximum gradient after the start of heat weight loss is plotted, and the temperature at the intersection of straight line A and straight line B is taken as the heat weight loss start temperature.

[0024] In the binder, the content ratio of the above resin A is preferably 80 parts by weight or more, more preferably 90 parts by weight or more, still more preferably 95 parts by weight or more, and particularly preferably 100 parts by weight with respect to 100 parts by weight of the binder.

[0025] In one embodiment, a filler granulated product is produced using a polymer liquid (polymer solution, polymer dispersion) containing a binder. Since the polymer liquid can efficiently and uniformly coat the filler surface, a filler granulated product with less powder loss, high disintegration hardness, and high bulk specific gravity can be obtained. Further, the dispersibility of the filler in the filler-containing resin composition can be greatly improved.

[0026] As the above binder, commercially available products may be used. Examples of commercially available products include Chem Pearl (registered trademark) manufactured by Mitsui Chemicals, Inc., HYPOD (registered trademark) of The Dow Chemical Company, Zicen manufactured by Sumitomo Seika Chemicals Co., Ltd., Sepoljion (registered trademark), Michem (registered trademark) manufactured by Michelman Japan Co., Ltd., Bondic (registered trademark) of DIC Corporation, and the like. Other preferred examples include water-soluble polyamides sold under the trade name AQ Nylon (registered trademark) manufactured by Toray Industries, Inc., aqueous sulfopolyester dispersions sold under the trade name Eastman AQ (registered trademark) manufactured by Eastman Chemical Company, salts of hexane-1,6-diamine and adipic acid (AH salts) sold by Ascend Performance that are diluted with water to form an aqueous polymer dispersion, water-soluble polyesters sold under the trade name Plascote (registered trademark) manufactured by Gohsei Chemical Industry Co., Ltd., and the like.

[0027] The content ratio of the above binder can be set to any appropriate ratio according to the size, shape, water absorbency, oil absorbency, bulk density, etc. of the above filler. The content ratio of the above binder is preferably 0.1 part by weight to 20 parts by weight, preferably 0.5 part by weight to 18 parts by weight, more preferably 1 part by weight to 18 parts by weight, and still more preferably 3 parts by weight to 15 parts by weight with respect to 100 parts by weight of the total amount of the above filler and binder. Within such a range, the binding force between the fillers is preferably exhibited, and a filler granulated product excellent in handleability can be obtained.

[0028] A-3. Dispersant As the above dispersant, a surfactant is preferably used. The hydrophilic / hydrophobic balance in the dispersant (surfactant) can be controlled by adjusting the degree of esterification of the compound serving as the dispersant, the type of fatty acid (presence or absence of a hydroxyl group, saturated or unsaturated fatty acid, alkyl chain length), and the degree of polymerization. By using a dispersant, the productivity (discharge rate) of the filler granulated product can be improved, and furthermore, the cleanability of the processing machine can be enhanced.

[0029] Moreover, if a filler granulate containing a dispersant is used to melt-knead a resin composition to produce a filler-containing resin composition, the surfactant action of the dispersant can enhance the filler dispersibility.

[0030] Examples of the above dispersant include fatty acids, fatty acid metal salts, fatty acid sulfonates, fatty acid amides, acrylamides, polyhydric alcohol fatty acid esters, polyglycerin fatty acid esters, etc. The dispersant may be used alone or in combination of two or more.

[0031] In one embodiment, the dispersant is at least one selected from the group consisting of polyhydric alcohol fatty acid esters, fatty acid amides, polyglycerin fatty acid esters, condensed hydroxy fatty acids, and alcohol esters of condensed hydroxy fatty acids.

[0032] The above polyhydric alcohol fatty acid ester is an ester compound composed of a polyhydric alcohol and a fatty acid. As the polyhydric alcohol fatty acid ester, for example, esters of polyhydric alcohols such as pentaerythritol and glycerin and fatty acids having 8 or more carbon atoms (preferably 8 to 24 carbon atoms, more preferably 10 to 22 carbon atoms) are used.

[0033] The above fatty acid amide is a compound having a structure formed by dehydration condensation of a fatty acid and ammonia or a primary or secondary amine. Examples of the above fatty acid amide include saturated fatty acid monoamides such as lauric acid amide, palmitic acid amide, stearic acid amide, and behenic acid amide.

[0034] The above polyglycerin fatty acid ester is an ester compound composed of polyglycerin and a fatty acid. Examples of the polyglycerin fatty acid ester include diglycerin palmitate, diglycerin stearate, diglycerin oleate, decaglycerin palmitate, decaglycerin stearate, decaglycerin oleate, etc.

[0035] As for the above-mentioned polyglycerol fatty acid ester, condensed hydroxy fatty acid, and alcohol ester of condensed hydroxy fatty acid, commercially available products may be used. Examples of commercially available products include "Chirabazole P-4", "Chirabazole VR-01", "Chirabazole VR-08" (polyglycerol fatty acid ester), "Chirabazole H-818" (alcohol ester of condensed hydroxy fatty acid), etc. manufactured by Sun Chemical Corporation. These may be used alone or in combination of two or more.

[0036] The content ratio of the above-mentioned dispersant is preferably 0.1 part by weight to 15 parts by weight, more preferably 0.1 part by weight to 10 parts by weight, and still more preferably 1 part by weight to 5 parts by weight with respect to 100 parts by weight of the total amount of the above-mentioned filler and binder.

[0037] A-4. Other Components The above-mentioned filler granulate may further contain any appropriate other components (additives) as necessary. Examples of additives include, for example, antioxidants, light stabilizers, foaming agents, ultraviolet absorbers, anti-blocking agents, heat stabilizers, impact modifiers, antibacterial agents, compatibilizers, plasticizers, tackifiers, processing aids, lubricants, coupling agents, flame retardants, deoxidizers, colorants, etc. The additives can be blended in the form of liquids, powders, pellets, granules, or in the form of masterbatches, etc., during the filler granulation or in the process of resin compounding. In one embodiment, the above-mentioned additives can be blended in a polymer liquid and granulated by a semi-wet granulator and then incorporated into the filler granulate.

[0038] B. Method for producing filler granulates The above-mentioned filler granulate can be manufactured by any appropriate method. The above-mentioned filler granulate can be obtained, for example, by subjecting a mixture containing the above-mentioned filler, the above-mentioned binder, and the above-mentioned dispersant added as necessary to a semi-wet granulation method.

[0039] In one embodiment, the method for manufacturing the filler granulated product includes a mixing step of mixing a filler and a binder, a granulation step of granulating the mixture obtained through the mixing step to obtain a granulated product precursor, and a drying step of drying the granulated product precursor. In one embodiment, in the mixing step, the binder is added as an aqueous liquid (aqueous solution or aqueous dispersion) containing the binder. Further, in one embodiment, a dispersant is further added in the mixing step.

[0040] When the aqueous liquid containing the binder is an aqueous solution (homogeneous system), the content ratio of the binder in the aqueous liquid containing the binder is preferably 1 part by weight to 70 parts by weight, more preferably 3 parts by weight to 50 parts by weight, and still more preferably 5 parts by weight to 30 parts by weight with respect to 100 parts by weight of the aqueous liquid. If it is within such a range, a mixed liquid excellent in the dispersibility of the binder can be obtained.

[0041] When the aqueous liquid containing the binder is an aqueous dispersion (heterogeneous system), the solid content concentration of the binder in the aqueous liquid containing the binder is preferably 1 wt% to 70 wt%, more preferably 3 wt% to 60 wt%, and still more preferably 5 wt% to 50 wt%. If it is within such a range, when mixing the aqueous liquid and the filler, the viscosity is preferably adjusted, and a mixed liquid excellent in the dispersibility of the binder can be obtained. By using such a mixed liquid, a filler granulated product preferably formed by binding the fillers together can be stably obtained.

[0042] The mixing ratio of the aqueous liquid containing the binder is preferably 1 part by weight to 70 parts by weight, more preferably 5 parts by weight to 50 parts by weight, and still more preferably 10 parts by weight to 30 parts by weight with respect to 100 parts by weight of the filler.

[0043] In the mixing process, other components (e.g., the above additives), a solvent (preferably water), etc. may be further mixed. In one embodiment, by adding these components, the mixing of the aqueous liquid containing the binder, the powdery thermoplastic polymer, and the filler is optimized. The water to be added is not particularly limited, and for example, tap water, distilled water, ion-exchanged water, hard water, soft water, etc. can be used.

[0044] In the mixing process, it is preferable to blend the components at room temperature and homogenize them using any suitable mixer. Examples of the mixer include a Henschel mixer, a kneader for powders (KDH, KDA, CKD, CPM) (Dalton), a Spartan mixer (SPM) (Dalton), an SP granulator (SPG) (Dalton), etc.

[0045] The mixing time in the mixing process can be any appropriate mixing time according to the type of components, the type of mixer, the component mixing ratio, etc. Preferably, the mixing time is set so that the surface of the filler is sufficiently and uniformly coated with the binder. In a high-speed stirrer such as a Henschel mixer or a Spartan mixer, the treatment time can be 1 to 10 minutes. On the other hand, in the case of a kneader for powders, a treatment time of several minutes to 60 minutes may be required.

[0046] In the granulation process, the compression granulation method is preferably adopted. Also, in the granulation process, the semi-wet granulation method may be preferably adopted. Examples of the compression granulation method / semi-wet granulation method include a disk pelletizer method, a tableting method, a briquetting method, etc. From the viewpoint of the balance between productivity and the quality of the obtained filler granulated product, the disk pelletizer method is preferably adopted.

[0047] The granulator of the disk pelleter type has, as its basic structure, one or two disks with a large number of holes ranging from 2 mm to 30 mm, and a roller for pumping the raw material into the holes of the disks. The raw material supplied between the disk and the roller or between two disks is pressed into the holes of the disk as the roller rotates, and a cylindrical extrudate is formed. Here, the disk holes are provided with a taper, and in the process of the above mixture passing through the holes, a mechanism is provided in which a compressive stress is applied from the outer periphery of the die holes. The length of this tapered hole is called the effective length. The extruded granule precursor can be cut by a cutter or the like on the back surface of the disk to obtain a pellet-shaped filler granule. The length of the granule precursor (and as a result, the filler granule) can be adjusted by the distance between the back surface of the disk and the cutter and the rotation speed of the roller. The distance between the back surface of the disk and the cutter is usually in the range of 1 mm to 30 mm, preferably in the range of 5 mm to 20 mm, and more preferably in the range of 5 mm to 10 mm.

[0048] More specifically, examples of the disk pelleter type include the roller-disk die method, the roller-ring die method, the double-die method, the flat-die method, etc. Examples of commercially available granulators of the disk pelleter type include the disk pelleter F series manufactured by Dalton.

[0049] As the drying method in the drying process, any appropriate method can be adopted. After the drying process, by performing treatment with a vibrating sieve or the like, a filler granule from which fine powder has been removed can be obtained. In the drying process, any appropriate drying equipment is used. For example, a vibrating fluidized bed dryer is preferable because it can perform drying efficiently in a short time. Examples include the vibrating fluidized bed dryer VDF series manufactured by Dalton.

[0050] C. Melt compound of resin and filler granulates In one embodiment, the filler granulate is used as a raw material for melt-kneading with an engineering resin. That is, in one embodiment, a melt compound of the filler granulate and the engineering resin is provided. The engineering resin is not particularly limited and may be, for example, at least one selected from the group consisting of polybutylene terephthalate (PBT), polycarbonate (PC), polyacetal (POM), polyamide (PA), modified polyphenylene ether (m-PPE), fluororesin, polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polysulfone (PSU), polyether sulfone (PES), polyarylate (PAR), polyamideimide (PAI), thermoplastic polyimide (TPI), polyetherimide (PEI), polyetheretherketone (PEEK), and liquid crystal polymer (LCP). As a method for producing the melt compound, any suitable method can be employed. For example, a kneader, a Banbury mixer, rolls, a single-screw or a multi-screw extruder with two or more screws can be used. Preferably, a twin-screw extruder is used. The melt-kneaded composition is pelletized.

Examples

[0051] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples in any way. Parts and % are based on weight unless otherwise specified.

[0052] [Example 1] 10 parts by weight of a dispersion of a binder (aqueous polyurethane dispersion, manufactured by DIC Corporation, trade name "Bondic 1940NE"; solid content concentration: 50% by weight, starting temperature of heat weight loss of polyurethane: 319°C, "B-1" in the table) and 3 parts by weight of a dispersant (polyglycerin condensed hydroxy fatty acid ester; manufactured by Sun Chemical Corporation, trade name "Chirabazole H818"; "C-1" in the table) were put into a 1-L plastic container and stirred for 20 minutes using a stirring blade at room temperature to obtain a mixture A. Next, 100 parts by weight of a filler (mica, product name "GM-4" manufactured by Chuzhou Grea Minerals Co.; average particle diameter: 18 μm; in the table, "A-1") was charged into a Henschel mixer (manufactured by Nippon Coke & Engineering Co., product name "5FM5C / I"; processing volume: 5 L), and while stirring the stirring blades at a rotational speed of 1,000 rpm, mixture A was charged into the Henschel mixer. Then, a stirring treatment was performed for 2 minutes to obtain mixture B. Mixture B was charged into a disk pelletizer (manufactured by Dalton, product name "Disk Pelletizer F-5 / 11-175) to obtain a pellet-shaped granule precursor. At this time, the pore diameter of the die was 3 mmφ, the thickness of the die plate was 15 mm, the effective length of the die hole was 10 mm, and the rotational speed of the roller of the disperter was 108 rpm. The obtained granule precursor was dried at 110 °C for 4 hours using a hot air circulation dryer to obtain a filler granule MB-1.

[0053] [Examples 2 to 4] Filler granules MB-2 to MB-4 were obtained in the same manner as in Example 1, except that the fillers, binders, and dispersants shown in Table 1 were used in the blending amounts shown in Table 1.

[0054] [Comparative Example 1] An attempt was made to granulate a mixture obtained by blending 20 parts by weight of tap water with 100 parts by weight of a filler (GM-4) without adding a dispersion liquid of a binder and a dispersant. However, there was no binding force and it easily disintegrated, and no granule could be obtained.

[0055] [Comparative Example 2] A filler granule (MB-C2) was obtained in the same manner as in Example 1, except that 20 parts by weight of a binder (B-5) was used for 100 parts by weight of a filler (JM-300, "A-2" in Table 2).

[0056] The specific details of each component used in Examples 1 to 4 and Comparative Examples 1 and 2 are as shown in Table 2. The initial temperature of the heating weight loss was determined by the measurement method described above. The thermogravimetric balance used was the product named "EXSTAR6000 TG / DTA6200" manufactured by Seiko Instruments Inc.

[0057]

Table 1

[0058]

Table 2

[0059] <Evaluation> The filler granulates obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were subjected to the following evaluations. The results are shown in Table 3. (1) Granulation property The obtained filler granulates were inspected, and the granulation property was evaluated according to the following criteria. 〇: Granulates with a diameter of 3 mmφ can be obtained. △: It forms the shape of filler granulates, but the binding force is insufficient and it is easy to collapse. ×: The filler clogs the die, or there is no binding property of the filler and it does not form granular matter. (2) Granulation speed The production speed (kg / Hr) of the filler granulates per hour was calculated. (3) Bulk density The dried filler granulates were allowed to fall naturally into a 1-liter measuring cylinder until it was full, and then weighed accurately at a volume of exactly 1 liter to calculate the bulk density (unit: kg / L) of the filler granulates. (4) Pellet size Twenty filler granulates were taken out, and the length and diameter of the granular matter were measured using vernier calipers, and the average value was calculated. (5) Moisture content The moisture content (unit: % by weight) remaining in the filler granulated product was measured using an infrared moisture meter (FD-660 manufactured by Kett Scientific Laboratory). (6) Measurement of disintegration strength Using a wooden hardness meter (manufactured by Shiro Sangyo Co., Ltd., product name "WPF1600-B"), the disintegration stress (unit: kg) of the dried filler granulated product was measured. The measured value was the average value of 25 filler granulated products. (7) Filler concentration 1 - 3 g of the filler granular material was collected, held in a crucible at 600 °C for 3 hours in an electric furnace to remove the binder component, and the filler concentration in the filler granulated product was calculated from the weight change (unit: % by weight).

[0060]

Table 3

[0061] As shown in Table 3, with MB-1 to MB-4, it is possible to obtain pellet-shaped filler granulated products with a stable pellet shape, high granulation speed, and appropriate hardness.

[0062] [Example 5] 78 parts by weight of a pellet mixture of polycarbonate (PC; manufactured by Mitsubishi Engineering Plastics Corporation, product name "Novarex 7022PJ"; MFR (300 °C, 1.2 kg load): 11 cm 3 / 10 min) and polyethylene terephthalate (PET; manufactured by Mitsubishi Engineering Plastics Corporation, product name "PBK1") (PC / PET = 65 / 35 (weight ratio)) and 22 parts by weight of the filler granulated product (MB-1) were mixed and supplied through an inlet provided at the most upstream part to a 40 mm single-screw extruder (manufactured by Isuzu Kikai Co., Ltd., model number "SV-40-32-EXT"; with damage, L / D = 32) to produce pellets of the mica-containing resin composition. The cylinder temperature of the extruder was set at 250 °C from the middle part and downstream of the extruder. Also, the rotational speed of the main screw of the single-screw extruder was set at 100 rpm. The melt-kneaded resin composition was extruded in a strand shape and cooled in a water-cooled bath to form pellets with a length of about 3 mm.

[0063] [Examples 6 to 9] Pellets of the resin composition were obtained in the same manner as in Example 5, except that the blending amount of the pellet mixture (PC / PET = 65 / 35 (weight ratio)) and the type and blending amount of the filler granulate were as shown in Table 4.

[0064] [Comparative Example 3] Melting and kneading of the resin composition was carried out in the same manner as in Example 6, except that 50 parts by weight of mica powder (A-1) was used instead of 55 parts by weight of the filler granulate (MB-1), and the blending amount of the pellet mixture (PC / PET = 65 / 35 (weight ratio)) was 50 parts by weight. The blending amount of the mica powder (A-1) in Comparative Example 3 was set to an amount substantially the same (50% by weight) as the content of the mica powder (A-1) in the resin composition obtained in Example 6. In Comparative Example 3, the mica powder (A-1) formed a bridge in the hopper for supplying raw materials to the extruder, resulting in poor penetration into the extruder screw and inability to produce stably. From the comparison between Example 6 and Comparative Example 2, it can be seen that by using the filler granulate (MB-1), even with a high concentration of filler blending amount, the feed neck of the mica powder (A-1) is eliminated, the productivity can be dramatically improved, and at the same time, a melt compound that can simultaneously satisfy the good dispersibility of the filler in the resin becomes possible.

[0065] [Comparative Example 4] Melting and kneading of the resin composition was carried out in the same manner as in Example 5, except that the filler granulate was changed to MB-C2. In Comparative Example 4, the binder of MB-C2 underwent significant decomposition at the melting and kneading temperature, generating a large amount of volatile matter, and the strand could not be pulled stably, so the resin composition could not be pelletized stably.

[0066] [Reference Example] Instead of 78 parts by weight of the pellet mixture (PC / PET = 65 / 35 (weight ratio)), 78 parts by weight of homopolypropylene (manufactured by Japan Polypropylene Corporation, trade name "Novatec MA1B", MFR 21 g / 10 min) was used, and pellets of the resin composition were obtained in the same manner as in Example 5 except that the cylinder temperature of the extruder was set to 190 °C after the middle section. When the filler dispersibility in the obtained resin composition was compared between Example 5 and the reference example, the reference example showed inferior filler dispersibility. MB-1 used in the reference example has a polyurethane-based resin as the resin as the binder, but due to its poor compatibility with the polypropylene resin which is the base polymer of the resin composition, the result is inferior filler dispersibility. From the comparison between Example 5 and the reference example, the filler granulate of the present invention has an excellent affinity (compatibility) of the binder with the engineering resin and can withstand a high melting processing temperature, so it is possible to blend a high concentration of filler with high dispersion without impairing the original properties of the engineering resin, indicating that it is an excellent filler granulate.

[0067] <Evaluation> The pellets of the resin compositions obtained in Examples 5 to 9, Comparative Example 3, Comparative Example 4, and the reference example were subjected to the following evaluations. The results are shown in Table 4. (a) Dispersibility of the filler in the resin composition The pellets of the resin composition were rolled by hot pressing to form a sheet with a thickness of about 0.5 mm. Through the sheet, the remaining filler aggregates were visually observed and evaluated according to the following criteria. AA: A good dispersion state with almost no observed filler aggregates A: A state with a small amount of remaining relatively small filler aggregates BB: A state with a considerably large amount of remaining relatively small filler aggregates B: A state with large filler aggregates (Dispersion state ranking: AA > A > BB > B (left is good)) (b) Granulatability of the resin composition pellets ○: Stable continuous granulation is possible ×: Unable to produce continuously

[0068]

Table 4

[0069] As is clear from Table 4, according to the present invention, even in the case of thermoplastic resins, particularly engineering resins that require processing at high temperatures, a resin composition excellent in filler dispersibility can be obtained.

Claims

1. A filler granulate for engineering resins, comprising a filler, a binder, and a dispersant, wherein the bulk density of the filler is from 0.01 kg / L to 1 kg / L, the binder contains a resin having a starting temperature of weight loss upon heating of 300°C or higher, the content ratio of the filler is from 80 parts by weight to 99.9 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder, the dispersant is at least one selected from the group consisting of polyglycerin fatty acid esters, condensed hydroxy fatty acids, and alcohol esters of condensed hydroxy fatty acids, the breaking stress of the filler granulate measured by a wooden hardness tester is from 1 kg to 5 kg, A filler granulate for engineering resins.

2. The filler granulate for engineering resins according to claim 1, wherein the filler is in powder form.

3. The filler granulate for engineering resins according to claim 1 or 2, wherein the binder is composed of at least one selected from the group consisting of urethane resins, epoxy resins, polyester resins, nylon resins, polyamide elastomer resins, and polyvinyl pyrrolidone resins.

4. The filler granulate for engineering resins according to any one of claims 1 to 3, wherein the content ratio of the dispersant is from 0.1 part by weight to 15 parts by weight with respect to 100 parts by weight of the total amount of the filler and the binder.

5. A mixing step of mixing the filler and the binder, A granulation step of granulating the mixture obtained through the mixing step to obtain a granulate precursor, and a drying step of drying the granulate precursor, A method for producing a filler granulate for engineering resins according to any one of claims 1 to 4.

6. The method for producing a filler granulate for engineering resins according to claim 5, comprising granulating by a semi-wet granulation method in the granulation step.

7. The method for producing a filler granulate for engineering resins according to claim 5 or 6, comprising granulating by a disk pelleter method in the granulation step.

8. Use of the filler granulate for engineering resins according to any one of claims 1 to 4 as a raw material for melt-kneading with an engineering resin.

9. The use of the filler granulate for engineering resins according to claim 8, wherein the engineering resin is at least one selected from the group consisting of polybutylene terephthalate (PBT), polycarbonate (PC), polyacetal (POM), polyamide (PA), modified polyphenylene ether (m-PPE), fluororesin, polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polysulfone (PSU), polyethersulfone (PES), polyarylate (PAR), polyamideimide (PAI), thermoplastic polyimide (TPI), polyetherimide (PEI), polyetheretherketone (PEEK), and liquid crystal polymer (LCP).

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