Inorganic filling material and inorganic filling material-reinforced thermoplastic resin

Abstract

This surface-treated inorganic filling material is obtained by treating an inorganic filling material (A) with: polyrotaxane (B), in which a cyclic molecule is modified with a graft chain having at least a reactive functional group; and a silane coupling agent (C). Provided is an inorganic filling material that constitutes an inorganic filling material-reinforced thermoplastic resin having an excellent balance of rigidity, strength, and toughness.

Description

Inorganic fillers and inorganic filler-reinforced thermoplastic resins

[0001] The present invention relates to a surface-treated inorganic filler treated with a polyrotaxane and a silane coupling agent, and an inorganic filler-reinforced thermoplastic resin.

[0002] Inorganic fillers are used as composite materials with thermosetting resins such as unsaturated polyester resins and epoxy resins, or thermoplastic resins such as polyamides and polyolefins. Composite materials containing resins and inorganic fillers are lightweight yet have excellent strength, rigidity, dimensional stability, and other properties, and are therefore widely used in general industrial applications, sporting goods applications, aerospace applications, and other fields.

[0003] Many proposals have been made to add inorganic fillers to resins in order to improve their strength and rigidity (see, for example, Patent Document 1). However, while adding inorganic fillers to resins improves their strength and elastic modulus, it also reduces their toughness and impact resistance.

[0004] As a method for improving the toughness of a fiber-reinforced thermoplastic resin while maintaining its rigidity, a method has been proposed in which polyrotaxane, which has the effect of preventing local stress concentration, is added to the fiber-reinforced thermoplastic resin (e.g., Patent Documents 2 and 3).

[0005] Japanese Patent Application Laid-Open No. 6-100774 International Publication No. 2018 / 043025 Japanese Patent Application Laid-Open No. 2020-55986

[0006] However, the technology of Patent Document 2 improved toughness while maintaining rigidity, resulting in ductile fracture, but had the problem of a significant decrease in strength. The technology of Patent Document 3 improved toughness while maintaining rigidity and strength, but had the problem of brittle fracture rather than ductile fracture. In inorganic filler-reinforced thermoplastic resins, interfacial delamination due to stress concentration at the inorganic filler interface is the starting point for fracture, so polyrotaxane is effective at the inorganic filler interface. In Patent Document 2, a large amount of polyrotaxane was blended with the thermoplastic resin to exert the stress dispersion effect of polyrotaxane at the fibrous filler interface, resulting in a decrease in the strength of the resin. Furthermore, in Patent Document 3, a method of using a fibrous filler having a compound with high affinity for polyrotaxane attached to its surface, or a method of directly treating the surface of the fibrous filler (C) with polyrotaxane, localizes the polyrotaxane at the interface between the thermoplastic resin and the fibrous filler, thereby preventing a decrease in strength. However, the method described in Patent Document 3 resulted in brittle fracture due to insufficient bonding between the polyrotaxane and the fibrous filler.

[0007] In view of the above, an object of the present invention is to provide an inorganic filler that can be used to form an inorganic filler-reinforced thermoplastic resin that has an excellent balance of rigidity, strength, and toughness, and that exhibits a ductile fracture mode while maintaining rigidity and strength.

[0008] To solve the above problems, the present invention has the following configurations: (1) A surface-treated inorganic filler obtained by treating an inorganic filler (A) with a polyrotaxane (B) whose cyclic molecules have been modified with graft chains having at least a reactive functional group, and a silane coupling agent (C). (2) The surface-treated inorganic filler according to (1), in which the silane coupling agent (C) has any one of an epoxy group, a glycidyl group, an acid anhydride, an isocyanate group, an isothiocyanate group, and a functional group containing a polymerizable double bond. (3) The surface-treated inorganic filler according to (1), obtained by treating an inorganic filler (A) with a polyrotaxane (B) whose cyclic molecules have been modified with graft chains having at least a reactive functional group, a silane coupling agent (C), and a compound (D) having in its molecule two or more amino groups and functional groups reactive with the reactive functional group of the polyrotaxane (B), in which the silane coupling agent (C) has at least one amino group. (4) The surface-treated inorganic filler according to any one of (1) to (3), wherein the inorganic filler (A) is an inorganic filler selected from the group consisting of glass fiber, talc, silica, clay, wollastonite, mica, and glass flake. (5) The surface-treated inorganic filler according to any one of (1) to (3), wherein the inorganic filler (A) is an inorganic filler selected from the group consisting of talc, silica, clay, wollastonite, mica, and glass flake. (6) An inorganic filler-reinforced thermoplastic resin containing at least the surface-treated inorganic filler according to any one of (1) to (5) and a thermoplastic resin (E), wherein the inorganic filler-reinforced thermoplastic resin contains 1 part by weight to 200 parts by weight of the surface-treated inorganic filler per 100 parts by weight of the thermoplastic resin (E).

[0009] The inorganic filler of the present invention makes it possible to obtain an inorganic filler-reinforced thermoplastic resin having an excellent balance of rigidity, strength, and toughness.

[0010] The present invention will now be described in further detail.

[0011] The surface-treated inorganic filler of the present invention is prepared by treating an inorganic filler (A) with at least a polyrotaxane (B) (hereinafter sometimes referred to as polyrotaxane (B)) whose cyclic molecules have been modified by graft chains, and a silane coupling agent (C). In the present invention, treating an inorganic filler (A) with a polyrotaxane (B) and a silane coupling agent (C) means adhering the polyrotaxane (B) and the silane coupling agent (C) to the surface of the inorganic filler (A). That is, the "surface-treated inorganic filler" of the present invention refers to an inorganic filler in which at least the polyrotaxane (B) and the silane coupling agent (C) are physically attached or chemically bonded to the surface of the inorganic filler (A). In the present invention, a component containing at least the polyrotaxane (B) and the coupling agent (C) may be referred to as a surface treatment agent. When the compound (D) described below is used, the compound (D) is also included in the surface treatment agent.

[0012] Furthermore, by blending 1 part by weight or more and 200 parts by weight or less of the surface-treated inorganic filler of the present invention with 100 parts by weight of thermoplastic resin (E), an inorganic filler-reinforced thermoplastic resin with an excellent balance of rigidity, strength, and toughness can be obtained. The inorganic filler-reinforced thermoplastic resin refers to a composition containing an inorganic filler and a thermoplastic resin. Hereinafter, the inorganic filler-reinforced thermoplastic resin may be referred to as a thermoplastic resin composition. The surface-treated inorganic filler efficiently exerts the stress dispersion effect of the polyrotaxane at the inorganic filler interface, thereby improving the rigidity, strength, and toughness of the inorganic filler-reinforced thermoplastic resin in a well-balanced manner. Heat applied during the production of the surface-treated inorganic filler or during mixing with the thermoplastic resin (E) causes the inorganic filler (A) and the polyrotaxane (B) and silane coupling agent (C) attached to their surfaces to react. This allows the surface-treated inorganic filler to efficiently exert the stress dispersion effect of the polyrotaxane at the inorganic filler interface, thereby improving the rigidity, strength, and toughness of the inorganic filler-reinforced thermoplastic resin in a well-balanced manner.

[0013] First, the inorganic filler (A) in the present invention will be described.

[0014] The inorganic filler (A) used in the present invention may be either a fibrous filler or a non-fibrous filler. Examples of the fibrous filler include fibrous or whisker-like fillers such as glass fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, silicon nitride whisker, wollastonite, and alumina silicate; and glass fiber coated with one or more metals selected from the group consisting of nickel, copper, cobalt, silver, aluminum, iron, and alloys thereof. Examples of non-fibrous fillers include non-swelling silicates such as talc, wollastonite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, and calcium silicate; swellable layered silicates such as Li-type fluorine taeniolite, Na-type fluorine taeniolite, Na-type tetrasilicic fluorine mica, and Li-type tetrasilicic fluorine mica; metal oxides such as silicon oxide, magnesium oxide, alumina, silica, diatomaceous earth, zirconium oxide, titanium oxide, iron oxide, zinc oxide, calcium oxide, tin oxide, and antimony oxide; calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, and dolomite. Examples of suitable clay fillers include metal carbonates such as tuffite and hydrotalcite; metal sulfates such as calcium sulfate and barium sulfate; metal hydroxides such as magnesium hydroxide, calcium hydroxide, aluminum hydroxide, and basic magnesium carbonate; smectite clay minerals such as montmorillonite, beidellite, nontronite, saponite, hectorite, and sauconite, and various clay minerals such as vermiculite, halloysite, kanemite, Kenyaite, zirconium phosphate, and titanium phosphate; flat glass, glass beads, glass flakes, ceramic beads, boron nitride, aluminum nitride, silicon carbide, calcium phosphate, carbon black, and graphite. Two or more of these may be used. Among these, inorganic fillers selected from glass fiber, talc, silica, clay, wollastonite, mica, flat glass, glass beads, and glass flakes are particularly preferred.

[0015] The surface-treated inorganic filler of the present invention is surface-treated with a polyrotaxane (B) in which a cyclic molecule is modified with a graft chain having a reactive functional group at its end. As described, for example, in Harada, A., Li, J. & Kamachi, M., Nature 356, 325-327, a rotaxane generally refers to a molecule in which a cyclic molecule is threaded through a linear molecule having bulky blocking groups at both ends. A single linear molecule threaded through multiple cyclic molecules is called a polyrotaxane.

[0016] Polyrotaxanes are composed of linear molecules and multiple cyclic molecules, with the linear molecules penetrating the openings of the multiple cyclic molecules, and both ends of the linear molecules have bulky blocking groups to prevent the cyclic molecules from detaching from the linear molecules. In polyrotaxanes, the cyclic molecules can move freely on the linear molecules, but the blocking groups prevent them from escaping from the linear molecules. In other words, the linear molecules and cyclic molecules maintain their shape through mechanical bonds rather than chemical bonds. Such polyrotaxanes have the effect of alleviating external stress and internal residual stress due to the high mobility of the cyclic molecules.

[0017] The linear molecule is not particularly limited as long as it penetrates the opening of the cyclic molecule and has a functional group capable of reacting with the block group. Preferred linear molecules include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; hydroxyl-terminated polyolefins such as polybutadiene diol, polyisoprene diol, polyisobutylene diol, poly(acrylonitrile-butadiene)diol, hydrogenated polybutadiene diol, polyethylene diol, and polypropylene diol; polyesters such as polycaprolactone diol, polylactic acid, polyethylene adipate, polybutylene adipate, polyethylene terephthalate, and polybutylene terephthalate; terminally functionalized polysiloxanes such as silanol-terminated polydimethylsiloxane; amino-terminated linear polymers such as amino-terminated polyethylene glycol, amino-terminated polypropylene glycol, and amino-terminated polybutadiene; and polyfunctional linear polymers having three or more functional groups capable of reacting with the block group per molecule. Among these, polyethylene glycol and / or amino-terminated polyethylene glycol are preferably used because the synthesis of polyrotaxanes is easy.

[0018] The number average molecular weight of the linear molecules is preferably 2,000 or more, which can improve the strength of the inorganic filler-reinforced thermoplastic resin. The number average molecular weight is more preferably 10,000 or more. On the other hand, the number average molecular weight is preferably 100,000 or less, which optimizes the interaction with the thermoplastic resin (E) and can further improve the toughness of the inorganic filler-reinforced thermoplastic resin. The number average molecular weight is more preferably 50,000 or less. Here, the number average molecular weight of the linear molecules refers to a value measured using gel permeation chromatography using hexafluoroisopropanol as a solvent, expressed in terms of polymethyl methacrylate.

[0019] The blocking group is not particularly limited as long as it can bond to the terminal functional group of the linear molecule and is sufficiently bulky to prevent the cyclic molecule from being detached from the linear molecule. Preferred blocking groups include dinitrophenyl groups, cyclodextrin groups, adamantyl groups, trityl groups, fluoresceinyl groups, pyrenyl groups, anthracenyl groups, and main or side chains of polymers having a number-average molecular weight of 1,000 to 1,000,000. Two or more of these may be used.

[0020] The cyclic molecule is not particularly limited as long as the linear molecule can penetrate the opening. Preferred cyclic molecules include cyclodextrins, crown ethers, cryptands, macrocyclic amines, calixarenes, and cyclophanes. Cyclodextrins are compounds in which multiple glucose molecules are linked in a ring via α-1,4-bonds. Compounds selected from α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin are more preferably used.

[0021] In the polyrotaxane (B), the cyclic molecules are modified with graft chains. The modification of the cyclic molecules with graft chains improves the affinity between the polyrotaxane (B) and the inorganic filler (A) interface. As a result, when the surface-treated inorganic filler of the present invention is blended with a thermoplastic resin (E) to form an inorganic filler-reinforced thermoplastic resin, the toughness can be improved while maintaining the rigidity and strength, and the rigidity, strength, and toughness can be improved in a balanced manner.

[0022] The graft chain is preferably composed of a polyester. From the viewpoints of compatibility with the thermoplastic resin (E) and solubility in organic solvents, an aliphatic polyester is more preferable as the graft chain. Examples of aliphatic polyesters include polylactic acid, polyglycolic acid, poly 3-hydroxybutyrate, poly 4-hydroxybutyrate, poly(3-hydroxybutyrate / 3-hydroxyvalerate), and poly(ε-caprolactone). Among these, poly(ε-caprolactone) is more preferable from the viewpoint of compatibility with the thermoplastic resin (E).

[0023] The graft chain has a reactive functional group at its end. The reactive functional group at the end of the graft chain is not particularly limited, but examples thereof include at least one group selected from the group consisting of a hydroxyl group, an amino group, a carboxyl group, an acid anhydride group, a glycidyl group, an isocyanate group, an isothiocyanate group, a thiol group, an oxazoline group, a sulfonic acid group, an acrylic group, and a methacrylic group.

[0024] The concentration of functional groups at the graft chain ends of the polyrotaxane (B) was 2 × 10 －５ mol / g or more 5×10 －４ The functional group concentration is preferably 2×10 －５ By making the functional group concentration 3×10 mol / g or more, the compatibility with the thermoplastic resin (E) can be improved. As a result, the toughness can be further improved while maintaining the strength of the inorganic filler-reinforced thermoplastic resin, and the strength and toughness can be improved in a more balanced manner. －５ On the other hand, the functional group concentration is preferably 5×10 －４ By setting the functional group concentration to 1×10 mol / g or less, aggregation due to association between functional groups of the polyrotaxane (B) and excessive chemical crosslinking with the thermoplastic resin (E) can be suppressed, and the generation of aggregates and gels can be suppressed, thereby further improving the toughness of the inorganic filler-reinforced thermoplastic resin. －４ mol / g or less is more preferable.

[0025] Here, the functional group concentration at the graft chain end of polyrotaxane (B) can be determined by titration. For example, when the functional group at the graft chain end is a carboxyl group, the carboxyl group concentration can be determined by the following method. An oven-dried sample is prepared by drying polyrotaxane (B) for 10 hours or more using a vacuum dryer at 80°C. 0.2 g of the oven-dried sample is dissolved in 25 ml of benzyl alcohol, and the solution is titrated with a 0.02 mol / L ethanol solution of potassium hydroxide to determine the carboxyl group concentration. The functional group concentrations of other functional groups can also be calculated by known methods.

[0026] The functional group at the graft chain end can be imparted, for example, by reacting a polyrotaxane whose cyclic molecules have been modified with graft chains with an introduction compound having a desired functional group and capable of reacting with the graft chain end. In this case, the concentration of the functional group at the graft chain end can be adjusted to a desired range by, for example, adjusting the charging ratio of the polyrotaxane whose cyclic molecules have been modified with graft chains and the introduction compound.

[0027] The weight-average molecular weight of the polyrotaxane (B) is preferably 100,000 or more, which can further improve the strength and toughness of the inorganic filler-reinforced thermoplastic resin. On the other hand, the weight-average molecular weight of the polyrotaxane (B) is preferably 1,000,000 or less, which can improve compatibility with the thermoplastic resin (E) and further improve the toughness of the inorganic filler-reinforced thermoplastic resin. Here, the weight-average molecular weight of the polyrotaxane (B) refers to a value calculated as polymethyl methacrylate, measured using gel permeation chromatography with hexafluoroisopropanol as a solvent.

[0028] The surface-treated inorganic filler of the present invention is surface-treated with a silane coupling agent (C), which is a compound having an alkoxysilyl group and a functional group reactive with the functional group at the end of the graft chain of the polyrotaxane (B).

[0029] Examples of the alkoxy group of the alkoxysilyl group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. From the viewpoint of reactivity, a methoxy group or an ethoxy group is preferred. The alkoxysilyl group may be a monoalkoxysilyl group, a dialkoxysilyl group, or a trialkoxysilyl group.

[0030] Examples of functional groups reactive with the functional groups at the graft chain ends of the polyrotaxane (B) include epoxy groups, glycidyl groups, acid anhydride groups, isocyanate groups, isothiocyanate groups, and functional groups containing a polymerizable double bond. Any one of epoxy groups, acid anhydride groups, isocyanate groups, and functional groups containing a polymerizable double bond is preferred. Examples of functional groups containing a polymerizable double bond include vinyl groups, acrylic groups, and methacrylic groups, with acrylic groups or methacrylic groups being preferred. Silane coupling agents containing these functional groups reactive with the functional groups at the graft chain ends of the polyrotaxane (B) can bond the inorganic filler (A) and the polyrotaxane (B) independently.

[0031] Examples of the isocyanate group include an aliphatic isocyanate group, an aromatic isocyanate group, and a blocked isocyanate group, and any of these may be used.

[0032] A blocked isocyanate group is a functional group in which an isocyanate group is protected and temporarily inactivated by reaction with a blocking agent. A compound having multiple blocked isocyanate groups is a blocked isocyanate compound. The blocking agent can be dissociated by heating to a predetermined temperature. As such a blocked isocyanate compound, an addition reaction product of an isocyanate compound and a blocking agent is used. Examples of isocyanate compounds that can react with a blocking agent include the compounds exemplified above as the isocyanate compound. Examples of blocked isocyanate compounds include isocyanurates, biurets, and adducts. Two or more blocked isocyanate compounds may be used in combination as needed.

[0033] Examples of blocking agents include phenol-based blocking agents such as phenol, cresol, xylenol, chlorophenol, and ethylphenol; lactam-based blocking agents such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam; active methylene-based blocking agents such as ethyl acetoacetate and acetylacetone; and methanol, ethanol, propanol, butanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl ether, methyl glycolate, butyl glycolate, diacetone alcohol, methyl lactate, and ethyl lactate. Examples of suitable blocking agents include alcohol-based blocking agents, oxime-based blocking agents such as formaldehyde oxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diacetyl monooxime, and cyclohexanone oxime, mercaptan-based blocking agents such as butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, thiophenol, methylthiophenol, and ethylthiophenol, acid amide-based blocking agents such as acetamide and benzamide, imide-based blocking agents such as succinimide and maleimide, amine-based blocking agents such as xylidine, aniline, butylamine, and dibutylamine, imidazole-based blocking agents such as imidazole and 2-ethylimidazole, and imine-based blocking agents such as methyleneimine and propyleneimine. These blocking agents may be used alone or in combination of two or more.

[0034] On the other hand, when the silane coupling agent (C) is a silane coupling agent having at least one amino group, the inorganic filler (A) and the polyrotaxane (B) cannot be bonded by the silane coupling agent alone, and therefore it is necessary to use in combination a compound (D) (hereinafter referred to as compound (D)) having two or more amino groups and functional groups reactive with the reactive functional group of the polyrotaxane (B) in the molecule. The functional group reactive with the reactive functional group of the polyrotaxane (B) is a functional group capable of forming a chemical bond with the reactive functional group present in the graft chain of the polyrotaxane (B) upon heating at a temperature range of 50°C to 250°C. The functional group possessed by the compound (D) is not limited as long as it is a functional group reactive with the amino group and the reactive functional group of the polyrotaxane (B). Examples of functional groups that can react with amino groups and reactive functional groups of polyrotaxane (B) include carboxyl groups, carboxyl group derivatives such as acid halides and acid anhydride groups, epoxy groups, glycidyl groups, and isocyanate groups. From the viewpoint of reactivity, groups selected from acid anhydride groups, epoxy groups, glycidyl groups, and isocyanate groups are preferred. The number of functional groups that can react with amino groups contained in compound (D) or reactive functional groups of polyrotaxane (B) is not limited as long as there are two or more of them in one molecule, and the functional groups may be composed of one type of functional group or several types of functional groups.

[0035] Compounds having two or more carboxyl groups or carboxyl group derivatives include aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and their derivatives, acrylic acid copolymers, maleic anhydride copolymers, etc. Compounds having two or more epoxy groups or glycidyl groups include aliphatic epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, novolac epoxy resins, etc. Compounds having two or more isocyanate groups include aliphatic diisocyanates such as hexamethylene diisocyanate; aromatic diisocyanates such as diphenylmethane diisocyanate and tolylene diisocyanate; and polyfunctional isocyanates such as polymeric MDI.

[0036] The weight-average molecular weight of compound (D) is preferably 100,000 or less, which improves compatibility with polyrotaxane and further improves the toughness of the inorganic filler-reinforced thermoplastic resin. The weight-average molecular weight is more preferably 80,000 or less, and even more preferably 60,000 or less. The weight-average molecular weight of compound (D) refers to a value calculated as polymethyl methacrylate, measured using gel permeation chromatography with hexafluoroisopropanol as a solvent.

[0037] The method for producing the surface-treated inorganic filler of the present invention is not particularly limited as long as the surface treatment agent is physically attached to the surface of the inorganic filler (A). A method in which a surface treatment agent-containing liquid in which the surface treatment agent is dissolved or dispersed is applied to the inorganic filler (A) in a single application, or a method in which each component of the surface treatment agent is individually dissolved or dispersed in a liquid in which the inorganic filler (A) is applied multiple times, is preferably used. In this case, the components constituting the surface treatment agent can be applied in any order. The solvent for dissolving or dispersing the surface treatment agent is not particularly limited, but examples include water, acetone, and ethanol. From the viewpoint of dispersibility of the polyrotaxane, water is preferably used.

[0038] Examples of means for applying the surface treatment agent to the inorganic filler include a method in which a slurry is prepared by dispersing the inorganic filler (A) in a surface treatment agent-containing liquid, and the mixture is mixed at room temperature, followed by filtering and drying the inorganic filler (A) to obtain a surface-treated inorganic filler, and a method in which the surface treatment agent-containing liquid is atomized and sprayed onto the inorganic filler (A). In particular, when a fibrous filler is used as the inorganic filler (A), a method in which the fibrous filler is immersed in the surface treatment agent-containing liquid via a roller, or a method in which the fibrous filler is brought into contact with a roller to which the surface treatment agent-containing liquid has adhered can also be used.

[0039] By kneading the surface-treated inorganic filler of the present invention with a thermoplastic resin (E), an inorganic filler-reinforced thermoplastic resin in which the inorganic filler (A) and the polyrotaxane (B) are chemically bonded can be obtained. This allows the polyrotaxane to efficiently exert its stress dispersion effect at the inorganic filler interface, thereby improving the rigidity, strength, and toughness of the inorganic filler-reinforced thermoplastic resin in a well-balanced manner. During the production of the surface-treated inorganic filler, the inorganic filler (A) and the polyrotaxane (B) may or may not be chemically bonded. A surface-treated inorganic filler in which the inorganic filler (A) and the polyrotaxane (B) are chemically bonded will remain an inorganic filler-reinforced thermoplastic resin in which the inorganic filler (A) and the polyrotaxane (B) are chemically bonded even after kneading with the thermoplastic resin (E). Even in the case of a surface-treated inorganic filler in which the inorganic filler (A) and the polyrotaxane (B) are not chemically bonded, the heat generated by kneading the inorganic filler (A) and the polyrotaxane (B) causes a silane coupling agent (C) or a silane coupling agent (C) having an amino group and a compound (D) having two or more functional groups in the molecule that can react with the amino group and the reactive functional group of the polyrotaxane (B) to react with the inorganic filler (A) and the polyrotaxane (B), thereby obtaining an inorganic filler-reinforced thermoplastic resin in which the inorganic filler (A) and the polyrotaxane (B) are chemically bonded. A surface-treated inorganic filler in which the inorganic filler (A) and the polyrotaxane (B) are chemically bonded is preferred. During the production of the surface-treated inorganic filler, a method for chemically bonding the inorganic filler (A) and the polyrotaxane (B) can be exemplified by heating the inorganic filler (A) coated with the polyrotaxane (B) at 40°C or higher and 250°C or lower. Heating at 40°C or higher can improve reactivity and increase the amount of polyrotaxane bonds in the surface-treated inorganic filler. On the other hand, heating at 250°C or lower can suppress decomposition of polyrotaxane (B). Another example is a method in which the surface treatment agent-containing liquid is applied to the inorganic filler (A) while being heated to 40°C or higher and 90°C or lower. By heating the surface treatment agent-containing liquid to 40°C or higher, reactivity can be improved and the amount of polyrotaxane bonds in the surface-treated inorganic filler can be increased. Furthermore, by heating at 90°C or lower, evaporation of the solvent in the surface treatment agent-containing liquid can be suppressed, and the concentration can be maintained constant.

[0040] Here, whether the inorganic filler (A) and the polyrotaxane (B) are chemically bonded can be determined by IR measurement. First, about 2 g of the surface-treated inorganic filler is washed with acetone to remove the polyrotaxane (B) that is not chemically bonded to the inorganic filler (A), and then dried. The dried surface-treated inorganic filler is mixed with KBr to form a tablet, and IR measurement is performed. The IR measurement is performed in accordance with JIS K0117:2017, and the 1750 cm IR spectrum derived from the C=O bond of polycaprolactone, a constituent of polyrotaxane (B), is measured. －１ When there is absorption in the vicinity, it can be determined that the inorganic filler (A) and the polyrotaxane (B) are chemically bonded.

[0041] In the surface-treated inorganic filler of the present invention, it is preferable that 0.01 to 20 parts by weight of polyrotaxane (B) be attached to the surface of the inorganic filler (A) per 100 parts by weight of the inorganic filler (A). When the amount of polyrotaxane (B) attached is 0.01 parts by weight or more, the stress relaxation effect of the polyrotaxane (B) is fully exerted, and the toughness of the inorganic filler-reinforced thermoplastic resin is improved. The amount of polyrotaxane (B) attached is preferably 0.1 parts by weight or more. On the other hand, when the amount of polyrotaxane (B) attached is 20 parts by weight or less, the strength and heat resistance of the resulting inorganic filler-reinforced thermoplastic resin can be maintained. The amount of polyrotaxane (B) attached is preferably 15 parts by weight or less, more preferably 10 parts by weight or less.

[0042] It is preferable that 0.01 to 5 parts by weight of the silane coupling agent (C) be attached to the surface of the inorganic filler (A) per 100 parts by weight of the inorganic filler (A). When the amount of the silane coupling agent (C) attached is 0.01 parts by weight or more, the amount of bonding between the inorganic filler (A) and the polyrotaxane (B) increases when the inorganic filler-reinforced thermoplastic resin is formed, thereby improving toughness. Furthermore, when the amount of the silane coupling agent (C) attached is 5.0 parts by weight or less, when the inorganic filler-reinforced thermoplastic resin is formed, it is possible to prevent a decrease in toughness due to the progression of crosslinking between thermoplastic resins or between polyrotaxanes (B). The amount of the silane coupling agent (C) attached is preferably 4 parts by weight or less, more preferably 3 parts by weight or less.

[0043] The surface of the surface-treated inorganic filler of the present invention may be coated with a coating agent such as a sizing agent, an antistatic agent, a surfactant, an antioxidant, a film-forming agent, a lubricant, etc., as needed, within the scope of not impairing the object of the present invention. Examples of the sizing agent include sizing agents containing a compound selected from carboxylic acid compounds, maleic anhydride compounds, urethane compounds, acrylic compounds, epoxy compounds, phenolic compounds, and derivatives thereof.

[0044] By blending the surface-treated inorganic filler of the present invention with a thermoplastic resin (E), an inorganic filler-reinforced thermoplastic resin having an excellent balance of rigidity, strength, and toughness can be obtained.

[0045] The thermoplastic resin (E) is not particularly limited as long as it is a resin exhibiting thermoplasticity, and examples thereof include styrene-based resins, fluororesins, polyoxymethylene, polyamide, polyester, polyimide, polyamideimide, vinyl chloride, olefin-based resins, polyacrylate, polyphenylene ether, polycarbonate, polyethersulfone, polyetherimide, polyetherketone, polyetheretherketone, polyarylene sulfide, cellulose derivatives, liquid crystal resins, and modified resins thereof, etc. Two or more of these may be contained.

[0046] Examples of styrene-based resins include PS (polystyrene), HIPS (high impact polystyrene), AS (acrylonitrile / styrene copolymer), AES (acrylonitrile / ethylene-propylene-non-conjugated diene rubber / styrene copolymer), ABS (acrylonitrile / butadiene / styrene copolymer), and MBS (methyl methacrylate / butadiene / styrene copolymer). Here, " / " indicates a copolymer, and the same applies hereinafter. Two or more of these may be contained. Among these, ABS is particularly preferred.

[0047] Specific examples of polyamides include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polypentamethylene adipamide (nylon 56), polytetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecane amide (nylon 11), polydodecanamide (nylon 12), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6 / 66), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 6 / 6T), and polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 6 / 6T). Examples of such copolymers include nylon 66 / 6I, polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polydodecanamide copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (nylon XD6), polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), polynonamethylene terephthalamide (nylon 9T), and copolymers thereof. Two or more of these may be used.

[0048] There are no particular restrictions on the degree of polymerization of the polyamide, but the relative viscosity, measured at 25°C in a 98% concentrated sulfuric acid solution with a resin concentration of 0.01 g / ml, is preferably in the range of 1.5 to 7.0, more preferably 2.2 to 4.0.

[0049] Examples of olefin resins include polypropylene, polyethylene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / propylene / non-conjugated diene copolymer, ethylene / ethyl acrylate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer, propylene-g-maleic anhydride copolymer, ethylene / propylene-g-maleic anhydride copolymer, methacrylic acid / methyl methacrylate / glutaric anhydride copolymer, etc. Two or more of these may be contained.

[0050] The polyester is preferably a polymer or copolymer having a residue of a dicarboxylic acid or its ester-forming derivative and a diol or its ester-forming derivative as the main structural unit.Among them, aromatic polyesters such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexanedimethylene terephthalate, polyethylene naphthalate, polypropylene naphthalate, polybutylene naphthalate, polyethylene isophthalate / terephthalate, polypropylene isophthalate / terephthalate, polybutylene isophthalate / terephthalate, polyethylene terephthalate / naphthalate, polypropylene terephthalate / naphthalate, and polybutylene terephthalate / naphthalate are particularly preferred, with polybutylene terephthalate being the most preferred.Two or more of these may be contained.In these polyesters, the ratio of terephthalic acid residues to all dicarboxylic acid residues is preferably 30 mol% or more, more preferably 40 mol% or more.

[0051] The polyester may also contain one or more residues selected from hydroxycarboxylic acids or their ester-forming derivatives, and lactones. Examples of hydroxycarboxylic acids include glycolic acid, lactic acid, hydroxypropionic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, o-hydroxybenzoic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, and 6-hydroxy-2-naphthoic acid. Examples of lactones include caprolactone, valerolactone, propiolactone, undecalactone, and 1,5-oxepan-2-one. Examples of polymers or copolymers containing these residues as structural units include aliphatic polyester resins such as polyglycolic acid, polylactic acid, polyglycolic acid / lactic acid, and polyhydroxybutyric acid / β-hydroxybutyric acid / β-hydroxyvaleric acid.

[0052] The melting point of the polyester is not particularly limited, but is preferably 120°C or higher, more preferably 220°C or higher, from the viewpoint of heat resistance. The upper limit is not particularly limited, but is preferably 300°C or lower, more preferably 280°C or lower. The melting point of the polyester is defined as the temperature of an endothermic peak that appears when, using a differential scanning calorimeter (DSC), the polyester is cooled from a molten state to 30°C at a temperature drop rate of 20°C / min in an inert gas atmosphere, and then heated at a temperature rise rate of 20°C / min. The temperature rise is preferably carried out up to the melting point + 40°C.

[0053] The amount of carboxyl end groups in the polyester is not particularly limited, but from the viewpoints of fluidity, hydrolysis resistance, and heat resistance, it is preferably 50 eq / t or less, and more preferably 10 eq / t or less. The lower limit is 0 eq / t. The amount of carboxyl end groups in the polyester is measured by dissolving the polyester resin in an o-cresol / chloroform (2 / 1, vol / vol) solvent and then titrating with 0.05 mol / L ethanolic potassium hydroxide using 1% bromophenol blue as an indicator.

[0054] The intrinsic viscosity of the polyester is not particularly limited as long as it can be melt-kneaded. However, from the viewpoint of moldability, the intrinsic viscosity of a 0.5 wt % o-chlorophenol solution measured at 25°C is preferably in the range of 0.36 to 1.60 dl / g, more preferably in the range of 0.50 to 1.25 dl / g, and even more preferably in the range of 0.7 to 1.0 dl / g.

[0055] The molecular weight of the polyester is not particularly limited, but from the viewpoint of heat resistance, the weight average molecular weight (Mw) is preferably in the range of 50,000 to 500,000, and more preferably in the range of 150,000 to 250,000. In the present invention, the weight average molecular weight (Mw) of the polyester is a relative value to the molecular weight of standard polymethyl methacrylate measured by gel permeation chromatography (GPC).

[0056] The method for producing the polyester is not particularly limited, and examples thereof include known polycondensation methods, ring-opening polymerization methods, etc. Either batch polymerization or continuous polymerization may be used, and either a transesterification reaction or a direct polymerization reaction may be applied.

[0057] Polycarbonates can be obtained by the phosgene method, in which phosgene is blown into a bifunctional phenolic compound in the presence of a caustic alkali and a solvent, or by the transesterification method, in which a bifunctional phenolic compound is transesterified with diethyl carbonate in the presence of a catalyst. Examples of polycarbonates include aromatic homopolycarbonates and aromatic copolycarbonates. The viscosity-average molecular weight of these aromatic polycarbonates is preferably in the range of 10,000 to 100,000.

[0058] Examples of bifunctional phenolic compounds include 2,2'-bis(4-hydroxyphenyl)propane, 2,2'-bis(4-hydroxy-3,5-dimethylphenyl)propane, bis(4-hydroxyphenyl)methane, 1,1'-bis(4-hydroxyphenyl)ethane, 2,2'-bis(4-hydroxyphenyl)butane, 2,2'-bis(4-hydroxy-3,5-diphenyl)butane, 2,2'-bis(4-hydroxy-3,5-dipropylphenyl)propane, 1,1'-bis(4-hydroxyphenyl)cyclohexane, 1-phenyl-1,1'-bis(4-hydroxyphenyl)ethane, etc. Two or more of these may be used.

[0059] Examples of polyarylene sulfides include polyphenylene sulfide (PPS), polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers thereof, block copolymers thereof, etc. Two or more of these may be used.

[0060] Polyarylene sulfide can be produced by commonly known methods, such as the method for obtaining a polymer having a relatively small molecular weight described in JP-B No. 45-3368, or the methods for obtaining a polymer having a relatively large molecular weight described in JP-B No. 52-12240 or JP-A No. 61-7332. Of course, the obtained polyarylene sulfide can also be used after being subjected to various treatments, such as crosslinking / polymerization by heating, heat treatment in an inert gas atmosphere such as nitrogen or under reduced pressure, washing with an organic solvent, hot water, an acid aqueous solution, or the like, or activation with a functional group-containing compound such as an acid anhydride, an amine, an isocyanate, or a functional group-containing disulfide compound.

[0061] A specific example of a method for crosslinking / polymerizing polyarylene sulfide by heating is a method in which heating is performed in a heating vessel under an oxidizing gas atmosphere such as air or oxygen, or under a mixed gas atmosphere of the oxidizing gas and an inert gas such as nitrogen or argon, at a predetermined temperature until a desired melt viscosity is obtained. The heat treatment temperature is preferably in the range of 200 to 270°C, and the heat treatment time is preferably in the range of 2 to 50 hours. From the viewpoint of efficient and more uniform heat treatment, it is preferable to heat in a heating vessel equipped with a rotary or stirring blade. A specific example of a method for heat treating polyarylene sulfide under an inert gas atmosphere such as nitrogen or under reduced pressure is a method in which heating is performed in an inert gas atmosphere such as nitrogen or under reduced pressure (preferably 7,000 Nm －２An example of such a method is a heat treatment method using a heating vessel (hereinafter referred to as "heat treatment vessel") at a temperature of 200 to 270°C for a heat treatment time of 2 to 50 hours. From the viewpoint of efficient and uniform heat treatment, heating is preferably performed in a rotary or stirring blade-equipped heating vessel. When washing polyarylene sulfide with an organic solvent, N-methylpyrrolidone, acetone, dimethylformamide, chloroform, etc. are preferably used as the organic solvent. Washing with an organic solvent can be performed, for example, by immersing the polyarylene sulfide resin in the organic solvent, with appropriate stirring or heating, if necessary. The washing temperature is preferably room temperature to 150°C. After organic solvent washing, the polyarylene sulfide is preferably washed several times with water or warm water to remove any remaining organic solvent. When treating polyarylene sulfide with hot water, distilled water or deionized water is preferably used. The hot water treatment is usually performed by adding a predetermined amount of polyarylene sulfide to a predetermined amount of water, and then heating and stirring the mixture at normal pressure or in a pressure vessel. The ratio of polyarylene sulfide resin to water is preferably 1 liter of water per 200 g or less of polyarylene sulfide. A specific method for acid-treating polyarylene sulfide is, for example, immersing the polyarylene sulfide resin in an acid or an aqueous acid solution, with appropriate stirring or heating as necessary. Acetic acid or hydrochloric acid is preferably used as the acid. The acid-treated polyarylene sulfide is preferably washed several times with water or warm water to remove residual acid or salt. The water used for washing is preferably distilled water or deionized water.

[0062] The melt viscosity of the polyarylene sulfide is preferably 80 Pa·s or less, and more preferably 20 Pa·s or less, under conditions of 310°C and a shear rate of 1000 / sec. There is no particular restriction on the lower limit of the melt viscosity, but it is preferably 5 Pa·s or more. Two or more polyarylene sulfides with different melt viscosities may be used in combination. The melt viscosity can be measured using a Capilograph (manufactured by Toyo Seiki Co., Ltd.) device under conditions of a die length of 10 mm and a die hole diameter of 0.5 to 1.0 mm.

[0063] Examples of cellulose derivatives include cellulose acetate, cellulose acetate butyrate, ethyl cellulose, etc. Two or more of these may be contained.

[0064] Among these thermoplastic resins, resins selected from polyamide resins, styrene-based resins, polycarbonate resins, polyester resins, and polyarylene sulfide resins are preferred because they have excellent affinity with the inorganic filler (A), and therefore have excellent moldability and can further improve the mechanical properties and surface appearance of molded articles. Among these, nylon 6 (polyamide 6), nylon 66 (polyamide 66), nylon 610 (polyamide 610), nylon 9T (polyamide 9T), ABS (acrylonitrile / butadiene / styrene copolymer), polycarbonate, polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), etc. are more preferably used.

[0065] The melting point of the thermoplastic resin (E) is preferably 150°C or higher and lower than 300°C. If the melting point is 150°C or higher, the heat resistance of the inorganic filler-reinforced thermoplastic resin can be improved. On the other hand, if the melting point is lower than 300°C, the processing temperature during the production of the inorganic filler-reinforced thermoplastic resin can be appropriately controlled, and the thermal decomposition of the polyrotaxane (B) can be suppressed. Here, the melting point of the thermoplastic resin (E) is defined as the temperature of the endothermic peak that appears when the thermoplastic resin (E) is cooled from the molten state to 30°C at a temperature drop rate of 20°C / min under an inert gas atmosphere using a differential scanning calorimeter, and then heated at a temperature rise rate of 20°C / min. The temperature rise is preferably performed up to the melting point + 40°C. However, if two or more endothermic peaks are detected, the temperature of the endothermic peak with the greatest peak intensity is taken as the melting point.

[0066] The content of the surface-treated inorganic filler in the inorganic filler-reinforced thermoplastic resin of the present invention is preferably 1 to 200 parts by weight per 100 parts by weight of the thermoplastic resin (E). When the content of the surface-treated inorganic filler is 1 part by weight or more, the effect of improving the mechanical properties and dimensional stability of the molded article can be obtained. The content of the surface-treated inorganic filler is more preferably 5 parts by weight or more, and even more preferably 10 parts by weight or more. On the other hand, by setting the content of the surface-treated inorganic filler to 200 parts by weight or less, floating of the inorganic filler on the surface of the molded article can be suppressed, resulting in excellent surface appearance. The content of the surface-treated inorganic filler is more preferably 175 parts by weight or less, and even more preferably 150 parts by weight or less.

[0067] It is preferable that a silane coupling agent be further blended into the inorganic filler-reinforced thermoplastic resin of the present invention. A silane coupling agent having a functional group reactive with the thermoplastic resin (E) is more preferable. Examples include silane coupling agents having any of the following functional groups: epoxy groups, glycidyl groups, acid anhydride groups, isocyanate groups, isothiocyanate groups, haloacyl groups, aldehyde groups, ketone groups, amino groups, vinyl groups, acrylic groups, and methacrylic groups. The incorporation of a silane coupling agent bonds the polyrotaxane (B) and the thermoplastic resin (E) at the inorganic filler interface, thereby more efficiently exhibiting the stress dispersion effect and improving the rigidity, strength, and toughness of the inorganic filler-reinforced thermoplastic resin in a balanced manner.

[0068] The amount of the silane coupling agent is preferably 0.01 parts by weight or more and 5 parts by weight or less per 100 parts by weight of the thermoplastic resin (E). When the amount of the silane coupling agent is 0.01 parts by weight or more, the polyrotaxane (B) and the thermoplastic resin (E) are efficiently bonded at the inorganic filler interface, and the stress dispersion effect of the polyrotaxane (B) is fully exhibited. The amount is preferably 0.05 parts by weight or more, more preferably 0.1 parts by weight or more. On the other hand, when the amount of the silane coupling agent is 5 parts by weight or more, crosslinking of the thermoplastic resin proceeds, resulting in a decrease in toughness. The amount is preferably 3 parts by weight or less, more preferably 2 parts by weight or less.

[0069] The inorganic filler-reinforced thermoplastic resin of the present invention can contain an elastomer to the extent that the object of the present invention is not impaired. Examples of elastomers include natural rubber, silicone rubber, fluororubber, thermoplastic elastomer, core-shell rubber, and ionomer. Among these, from the viewpoint of compatibility with the thermoplastic resin (E), elastomers selected from thermoplastic elastomers and core-shell rubbers are preferred, and thermoplastic elastomers are more preferred. When a thermoplastic elastomer is used as the elastomer, the thermoplastic elastomer is also counted as the thermoplastic resin (E) in calculating the content ratio of each component in the inorganic filler-reinforced thermoplastic resin.

[0070] The inorganic filler reinforced thermoplastic resin of the present invention may contain various additives within the range that does not impair the object of the present invention.

[0071] Specific examples of the various additives include heat stabilizers, plasticizers, crystal nucleating agents, metal soaps, mold release agents, coloring inhibitors, lubricants, ultraviolet inhibitors, colorants, flame retardants, foaming agents, etc. When these additives are contained, the content thereof is preferably 10 parts by weight or less, and more preferably 1 part by weight or less, per 100 parts by weight of the thermoplastic resin (E) in order to fully utilize the characteristics of the thermoplastic resin (E).

[0072] The method for producing the inorganic filler-reinforced thermoplastic resin of the present invention is not particularly limited, and examples thereof include a method of kneading raw materials in a molten state and a method of mixing them in a solution state. From the viewpoint of improving reactivity, a method of kneading in a molten state is preferred. Examples of melt-kneading devices for kneading in a molten state include single-screw extruders; multi-screw extruders such as twin-screw extruders and four-screw extruders; extruders such as twin-screw single-screw composite extruders, and kneaders. From the viewpoint of productivity, an extruder capable of continuous production is preferred, and from the viewpoint of improving kneading ability, reactivity, and productivity, a twin-screw extruder is more preferred.

[0073] Hereinafter, an example of producing the inorganic filler-reinforced thermoplastic resin of the present invention using a twin-screw extruder will be described. From the viewpoint of suppressing thermal degradation of the polyrotaxane (B) and further improving toughness, the maximum resin temperature in the melt-kneading step is preferably 300°C or lower. On the other hand, the maximum resin temperature is preferably equal to or higher than the melting point of the thermoplastic resin (E). Here, the maximum resin temperature refers to the highest temperature measured by resin thermometers evenly installed at multiple positions in the extruder.

[0074] In addition, the ratio of the extrusion rate of the inorganic filler-reinforced thermoplastic resin to the screw rotation speed in the melt-kneading process is preferably 0.01 kg / h or more, more preferably 0.05 kg / h or more, per rpm of screw rotation speed, from the viewpoint of further suppressing thermal degradation of the thermoplastic resin (E) and the polyrotaxane (B). On the other hand, from the viewpoint of further promoting the reaction between the thermoplastic resin (E) and the polyrotaxane (B) resin, the extrusion rate is preferably 1 kg / h or less per rpm of screw rotation speed. Here, the extrusion rate refers to the weight (kg) of the inorganic filler-reinforced thermoplastic resin extruded from the extruder per hour. In addition, the extrusion rate per rpm of screw rotation speed is the value obtained by dividing the extrusion rate by the screw rotation speed.

[0075] The inorganic filler-reinforced thermoplastic resin thus obtained can be molded by known methods to obtain various molded products such as sheets, films, etc. Examples of molding methods include injection molding, injection compression molding, extrusion molding, compression molding, blow molding, and press molding.

[0076] The inorganic filler-reinforced thermoplastic resin and molded articles thereof of the present invention can be utilized to their advantage in various applications, such as automobile parts, electrical and electronic parts, building materials, various containers, daily necessities, household goods, and sanitary products, etc. In particular, they are particularly preferably used for automobile exterior parts, which require toughness and rigidity, as well as for automobile electrical parts, automobile underhood parts, automobile gear parts, and electrical and electronic parts such as housings, connectors, and reflectors.Specifically, automotive engine peripheral parts such as engine covers, air intake pipes, timing belt covers, intake manifolds, filler caps, throttle bodies, and cooling fans; automotive underhood parts such as cooling fans, radiator tank tops and bases, cylinder head covers, oil pans, brake piping, fuel piping tubes, and exhaust gas system parts; automotive gear parts such as gears, actuators, bearing retainers, bearing cages, chain guides, and chain tensioners; automotive interior parts such as shift lever brackets, steering lock brackets, key cylinders, door inner handles, door handle cowls, interior mirror brackets, air conditioning switches, instrument panels, console boxes, glove boxes, steering wheels, and trim; front fenders, rear fenders, fuel lids, door panels, cylinder head covers, door mirror stays, tailgate panels, license garnishes, roof rails, and engine Suitable examples of the components include automotive exterior parts such as mount brackets, rear garnishes, rear spoilers, trunk lids, rocker moldings, moldings, lamp housings, front grilles, mudguards, and side bumpers; intake and exhaust system parts such as air intake manifolds, intercooler inlets, exhaust pipe covers, inner bushings, bearing retainers, engine mounts, engine head covers, resonators, and throttle bodies; engine coolant system parts such as chain covers, thermostat housings, outlet pipes, radiator tanks, alternators, and delivery pipes; automotive electrical parts such as connectors, wire harness connectors, motor parts, lamp sockets, sensor-mounted switches, and combination switches; and electrical and electronic parts such as SMT-compatible connectors, sockets, card connectors, jacks, power supply parts, switches, sensors, capacitor base plates, relays, resistors, fuse holders, coil bobbins, IC and LED-compatible housings, and reflectors.Furthermore, the inorganic filler-reinforced thermoplastic resin and molded articles thereof of the present invention can be suitably used in sports applications, taking advantage of their excellent high impact resistance and non-destructive properties, and are suitable for use in golf-related products such as golf clubs, shafts, grips, golf balls, etc.; sports racket-related products such as tennis rackets and badminton rackets and their strings; sports personal protective equipment such as masks, helmets, breast pads, elbow pads, knee pads, etc. for American football, baseball, softball, etc., and clothing-related products such as sportswear; shoe-related products such as soles for sports shoes; fishing tackle-related products such as fishing rods and fishing lines; summer sports related products such as surfing; winter sports related products such as skiing and snowboarding; and other indoor and outdoor sports related products.

[0077] The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The following raw materials were used to obtain the resin compositions of the examples.

[0078] <Inorganic filler> (A-1): Glass fiber (E-glass composition, diameter 10 μm, fiber length 3 mm) (A-2): Talc (average particle diameter: 10 μm) (A-3): Mica (average particle diameter: 50 μm, average thickness: 1.0 μm, aspect ratio: 50).

[0079] <Polyrotaxane> (B-1): Polyrotaxane (Cellm® Super Polymer SH1300P, manufactured by Advanced Soft Materials Co., Ltd.). This polyrotaxane has α-cyclodextrin modified with a graft chain consisting of poly(ε-caprolactone) whose cyclic molecules have hydroxyl groups at their termini, polyethylene glycol as linear molecules, and adamantane as block groups. The number-average molecular weight of the polyethylene glycol linear molecules is 15,000, and the overall weight-average molecular weight is 180,000.

[0080] Here, the number-average molecular weight of polyethylene glycol and the weight-average molecular weight of polyrotaxane are values ​​measured by gel permeation chromatography using hexafluoroisopropanol as a solvent and Shodex HFIP-806M (two columns) + HFIP-LG as columns, and are values ​​calculated as polymethyl methacrylate.

[0081] <Silane coupling agents> (C-1): 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (silane coupling agent KBM-303, manufactured by Shin-Etsu Chemical Co., Ltd.), molecular weight: 246.4 g / mol. (C-2): 3-aminopropyltrimethoxysilane (silane coupling agent KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.), molecular weight: 221.3 g / mol.

[0082] <Compound D> (D-1): A copolymer obtained by copolymerizing 40 parts by weight of maleic anhydride, 50 parts by weight of methyl acrylate, and 10 parts by weight of methyl methacrylate, having a weight-average molecular weight of 20,000 g / mol.

[0083] <Thermoplastic Resin> (E-1): Polyamide 6 resin ("Amilan" (registered trademark) manufactured by Toray Industries, Inc.), ηr = 2.70, melting point 225°C.

[0084] Here, the relative viscosity ηr was measured in a 0.01 g / ml solution of 98% concentrated sulfuric acid at 25°C. The melting point was measured using a differential scanning calorimeter, and was determined as the temperature of the endothermic peak that appeared when the polyamide was cooled from a molten state to 30°C at a rate of 20°C / min in an inert gas atmosphere, and then heated to 265°C at a rate of 20°C / min. (E-2): Polybutylene terephthalate resin ("Treycon" (registered trademark) manufactured by Toray Industries, Inc.), η=0.85 dl / g, melting point 223°C.

[0085] Here, the intrinsic viscosity η was measured at 25°C using an o-chlorophenol solution. The melting point was measured using a differential scanning calorimeter, and was defined as the temperature of an endothermic peak that appeared when polybutylene terephthalate was cooled from a molten state to 30°C at a temperature decrease rate of 20°C / min in an inert gas atmosphere, and then heated to 263°C at a temperature increase rate of 20°C / min. (E-3): Polyamide 66 resin ("Amilan" (registered trademark) manufactured by Toray Industries, Inc.), ηr = 2.78, melting point 260°C.

[0086] (Reference Examples 1 to 10) <Preparation of Surface-Treated Inorganic Filler> An aqueous dispersion was prepared by dispersing surface treatment agents (polyrotaxane (B), silane coupling agent (C), and compound (D)) in 100 parts by weight of water in the proportions shown in Table 1. Inorganic filler (A) was added to the aqueous dispersion and stirred at room temperature for 5 minutes. Thereafter, the inorganic filler was separated from the aqueous dispersion and dried under reduced pressure at room temperature for 6 hours to obtain a surface-treated inorganic filler. The amount of surface treatment agent adhered to the obtained surface-treated inorganic filler was measured by the method shown below, and the results are shown in Table 1.

[0087] <Composition Analysis of Surface-Treated Inorganic Filler> Approximately 2 g of the surface-treated inorganic filler was weighed, and the weight was designated W1. The surface-treated inorganic filler was then placed in an electric furnace set at 450°C in a 50 mL / min nitrogen stream for 60 minutes to completely pyrolyze the surface treatment agent, yielding an inorganic filler. The inorganic filler was then transferred to a container in a 20 L / min dry nitrogen stream and cooled for 15 minutes. The inorganic filler was then weighed, and its weight was designated W2. The total amount of surface treatment agent attached to the surface-treated inorganic filler was calculated using the following formula. Each attachment amount was calculated from the ratio of polyrotaxane (B) to silane coupling agent (C) in the aqueous dispersion. Attachment amount (parts by weight) = [W1 (g) - W2 (g)] / [W1 (g)] × 100. In this example, measurements were performed twice, and the average value was designated as the attachment amount. The results are shown in Table 1.

[0088] <Measurement of the Presence or Absence of Chemical Bonds between the Inorganic Filler Surface and Polyrotaxane> Approximately 2 g of the surface-treated inorganic filler was washed with acetone and dried. The dried surface-treated inorganic filler was mixed with KBr to form a tablet, which was then subjected to IR measurement. The IR measurement was performed in accordance with JIS K0117:2017 using an IRPrestige 21 manufactured by Shimadzu Corporation. The IR peak at 1750 cm originating from the C=O bond of polycaprolactone, a constituent of polyrotaxane (B), was measured. －１ When absorption was observed in the vicinity of the point, it was determined that the surface of the inorganic filler (A) and the polyrotaxane (B) were chemically bonded.

[0089] (Reference Examples 11 to 20) <Preparation of Surface-Treated Inorganic Filler> Polyrotaxane (B) and other components were dispersed in 100 parts by weight of water at the weight ratios shown in Table 2. Inorganic filler (A) was added to the aqueous dispersion and stirred at 60°C for 30 minutes. Thereafter, the inorganic filler was separated from the aqueous dispersion and dried at 130°C for 6 hours to obtain a surface-treated inorganic filler. In the same manner as above, the composition of the surface-treated inorganic filler was analyzed and the presence or absence of chemical bonding between the inorganic filler surface and the polyrotaxane was measured, and the results are shown in Table 2.

[0090] (Examples 1 to 29, Comparative Examples 1 to 8, Reference Examples 21 and 22) <Production of inorganic filler-reinforced thermoplastic resin> Using a twin-screw extruder (TEX30α manufactured by The Japan Steel Works) set at a cylinder temperature of 250 ° C. (280 ° C. for Examples 19 to 20 and Comparative Example 6) and a screw rotation speed of 200 rpm, the thermoplastic resin (E) was fed from the main feeder to obtain the composition shown in Tables 3 to 6, and the surface-treated inorganic filler or inorganic filler (A) obtained in each Reference Example was fed from the side feeder and melt-kneaded. The extruded strands were pelletized to obtain pellets. The results of evaluation of the obtained pellets by the methods shown below are shown in Tables 3 to 6.

[0091] <Bending Test> The pellets obtained in each Example and Comparative Example were dried under reduced pressure at 80°C for 12 hours, and then injection molded using an injection molding machine (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd.) under conditions of a cylinder temperature of 250°C (290°C for Examples 19-20 and Comparative Example 6) and a mold temperature of 80°C, to produce multipurpose test specimens Type A obtained in accordance with ISO 3167. Bending test specimens obtained from these multipurpose test specimens were subjected to a bending test in accordance with ISO 178 (2001) using a Tensilon RTA-1T bending tester (manufactured by Orientec Co., Ltd.) at a crosshead speed of 2 mm / min to determine the flexural modulus, maximum bending strength, and bending elongation at break. The results are shown in Tables 3 to 6. The bending elongation at break N.B. indicates a state in which the specimen exceeds the maximum point during the bending test and does not break when the strength is 90% of the maximum point.

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098] Comparisons of Examples 1 to 6, 11 to 12 with Comparative Examples 1, 7 to 8, Examples 17 and 18 with Comparative Example 5, Examples 19 and 20 with Comparative Example 6, and Examples 21 to 29 with Comparative Example 2 reveal that the presence of polyrotaxane (B) and silane coupling agent (C) improves the breaking elongation while maintaining high levels of rigidity and strength of the glass fiber reinforced thermoplastic resin. Furthermore, comparisons of Examples 7 and 8 with Comparative Example 3, and Examples 9 and 10 with Comparative Example 4 reveal that the presence of a component that bonds the polyrotaxane and glass fiber also exerts a toughness-improving effect in inorganic fillers such as talc and mica.

[0099] Furthermore, a comparison of Examples 4 and 5 with Reference Examples 21 and 22 reveals that when the silane coupling agent is a silane coupling agent having an amino group, the toughness-improving effect is exerted by including a compound having, in the molecule, two or more functional groups capable of reacting with the amino group and the reactive functional group of the polyrotaxane (B).

Claims

1. An inorganic filler (A) is treated with a polyrotaxane (B) in which a cyclic molecule is modified by a graft chain having at least a reactive functional group, a silane coupling agent (C), and a compound (D) having two or more amino groups and functional groups capable of reacting with the reactive functional groups of the polyrotaxane (B) in the molecule, and the surface-treated inorganic filler is such that the silane coupling agent (C) has at least one amino group.

2. The surface-treated inorganic filler according to Claim 1, wherein the inorganic filler (A) is an inorganic filler selected from glass fiber, talc, silica, clay, wollastonite, mica, and glass flake.

3. The surface-treated inorganic filler according to Claim 2, wherein the inorganic filler (A) is an inorganic filler selected from talc, silica, clay, wollastonite, mica, and glass flake.

4. An inorganic filler-reinforced thermoplastic resin containing at least the surface-treated inorganic filler according to any one of Claims 1 to 3 and a thermoplastic resin (E), and containing 1 part by weight or more and 200 parts by weight or less of the surface-treated inorganic filler with respect to 100 parts by weight of the thermoplastic resin (E).