Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L33/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
  • C08L33/04—Homopolymers or copolymers of esters
  • C08L33/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, which oxygen atoms are present only as part of the carboxyl radical
  • C08L33/10—Homopolymers or copolymers of methacrylic acid esters
  • C08L33/12—Homopolymers or copolymers of methyl methacrylate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
  • B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
  • B29C48/40—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/92—Measuring, controlling or regulating
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/12—Esters of monohydric alcohols or phenols
  • C08F220/14—Methyl esters, e.g. methyl (meth)acrylate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/12—Esters of monohydric alcohols or phenols
  • C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
  • C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
  • C08F220/1804—C4-(meth)acrylate, e.g. butyl (meth)acrylate, isobutyl (meth)acrylate or tert-butyl (meth)acrylate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/05—Alcohols; Metal alcoholates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/04—Oxygen-containing compounds
  • C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/16—Nitrogen-containing compounds
  • C08K5/20—Carboxylic acid amides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C2948/00—Indexing scheme relating to extrusion moulding
  • B29C2948/92—Measuring, controlling or regulating
  • B29C2948/92504—Controlled parameter
  • B29C2948/92704—Temperature
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/0001—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
  • B29K2033/04—Polymers of esters
  • B29K2033/08—Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
  • B29K2033/04—Polymers of esters
  • B29K2033/12—Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2035/00—Use of polymers of unsaturated polycarboxylic acids or derivatives thereof as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/0088—Blends of polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
  • B29K2105/16—Fillers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2421/00—Use of unspecified rubbers as filler
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2011/00—Optical elements, e.g. lenses, prisms
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/30—Vehicles, e.g. ships or aircraft, or body parts thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/712—Containers; Packaging elements or accessories, Packages
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/753—Medical equipment; Accessories therefor
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
  • C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure

Definitions

• the present invention relates to a methacrylic resin composition for injection molding or extrusion molding, a resin molding obtained by molding the methacrylic resin composition for injection molding or extrusion molding, and a method for producing the same.
• (meth)acrylic resin is used in vehicle interior and exterior materials such as tail lamp covers, head lamp covers, meter panels, pillar garnishes, front grilles, and emblems. building materials; housing equipment components such as bathroom vanities, bathtubs, and flush toilets; optical components such as lenses and light guides; containers for cosmetics, medical components such as cuvettes, etc. ing.
• methacrylic resins are often used for design parts due to their transparency, and excellent transparency is required.
• Patent Document 1 discloses a thermoplastic resin composition containing an acrylic resin, a silicone compound, and a melt elasticity-imparting agent. is disclosed.
• Patent Literature 2 discloses a methacrylic resin composition containing an acrylic resin and a polyester-modified silicone having a specific molecular weight as a methacrylic resin composition excellent in scratch resistance of resin molded articles.
• thermoplastic resin composition disclosed in Patent Document 1 the acrylic resin is blended with a silicone compound to improve scratch resistance and chemical resistance, but the acrylic resin and the silicone compound are not compatible. Inadequate.
• acrylic resins and silicone compounds have different refractive indices, there is a problem that the transparency is lowered, and it has been difficult to apply them to transparent applications and deep-colored coloring applications.
• the methacrylic resin composition disclosed in Patent Document 2 has the problem that it needs to be molded at a mold temperature of 70°C or higher in order to ensure sufficient scratch resistance.
• the present invention solves the above-mentioned problems of the prior art, and a methacrylic resin composition for injection molding or extrusion molding that can obtain a resin molded article having excellent transparency and scratch resistance even at a mold temperature lower than 70 ° C.
• the purpose is to provide goods.
• the present inventors added a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols to an acrylic resin (A) without using a polyester-modified silicone, and By containing the above methacrylic polymer (C) in a specific ratio, the scratch resistance is remarkably exhibited, and the resin has excellent transparency and scratch resistance even at a mold temperature lower than 70 ° C. It was found that a molded article can be obtained. That is, the gist of the present invention is as follows.
• component (A), component (B) and component (C) are included, and the ratio represented by [mass of component (C)]/[mass of component (B)] is 0.01 to 50 A methacrylic resin composition for injection molding or extrusion molding.
• Component (A) Acrylic resin having a weight average molecular weight of less than 200,000
• Component (B) At least one selected from fatty acids, fatty acid derivatives and fatty alcohols
• the content of the component (D) is 0 parts by mass with respect to 100 parts by mass of the methacrylic resin composition for injection molding or extrusion molding.
• component (A), component (B) and component (C) are included, and the ratio represented by [mass of component (C)]/[mass of component (B)] is 0.01 to 50
• a method for producing a resin molded article comprising: obtaining a resin molded article by injection molding or extrusion molding the methacrylic resin composition.
• Component (B) At least one selected from fatty acids, fatty acid derivatives and fatty alcohols
• component (C) Weight average molecular weight of 200,000 or more methacrylic polymer
• component (A), component (B) and component (C) are included, and the ratio represented by [mass of component (C)]/[mass of component (B)] is 0.01 to 50 Use for injection molding or extrusion molding of a methacrylic resin composition.
• the ratio of the following component (A), component (B), and component (C) represented by [mass of component (C)]/[mass of component (B)] is 0.01 to 50.
• a resin molded product obtained by mixing as follows and injection molding or extrusion molding the mixture.
• component (A) Acrylic resin having a weight average molecular weight of less than 200,000
• component (B) At least one selected from fatty acids, fatty acid derivatives and fatty alcohols
• component (C) Weight average molecular weight of 200,000 or more methacrylic polymer
• the methacrylic resin composition for injection molding or extrusion molding of the present invention it is possible to improve the scratch resistance of the resulting resin molding, and furthermore to make it excellent in transparency. Moreover, since it is excellent in moldability, it is possible to improve the problem of restrictions on molding conditions and mold structure in order to exhibit sufficient scratch resistance.
• the repeating units may be units directly formed by a polymerization reaction, or some of the units may be converted to another structure by treating the polymer. "% by mass” and “parts by mass” are synonymous with “% by mass” and “parts by weight”, and “% by mass” indicates the content ratio of a given component contained in 100% by mass of the total amount.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention contains the following component (A), component (B) and component (C), and [mass of component (C)]/[mass of component (B) mass] is 0.01 to 50.
• Component (A) an acrylic resin having a mass average molecular weight of less than 200,000 (hereinafter sometimes referred to as “acrylic resin (A)”)
• Component (B) At least one selected from fatty acids, fatty acid derivatives and fatty alcohols (hereinafter sometimes referred to as “compound (B) containing at least one selected from fatty acids, fatty acid derivatives and fatty alcohols") be.
• Component (C) a methacrylic polymer having a mass average molecular weight of 200,000 or more (hereinafter sometimes referred to as "a methacrylic polymer (C) having a mass average molecular weight of 200,000 or more").
• the methacrylic resin composition for injection molding or extrusion molding of the present invention comprises an acrylic resin (A), a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a mass average molecular weight of
• a methacrylic polymer (C) having a molecular weight of 200,000 or more at a specific ratio a resin molded product obtained by molding this methacrylic resin composition for injection molding or extrusion molding (hereinafter referred to as the "obtained resin The molded article") has excellent transparency and scratch resistance even at a mold temperature lower than 70°C.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention may further contain no component (D) below, or may contain it in a predetermined proportion or less.
• Component (D) rubber particles having a multilayer structure (hereinafter sometimes referred to as "rubber particles having a multilayer structure (D)")
• the acrylic resin (A) having a weight average molecular weight of less than 200,000 is one of the constituents of the methacrylic resin composition for injection molding or extrusion molding of the present invention.
• the acrylic resin (A) in the present invention preferably contains 50% by mass or more of repeating units derived from methyl methacrylate (hereinafter referred to as "methyl methacrylate units") relative to the total mass of the acrylic resin (A). It is more preferably contained in an amount of 80% by mass or more, particularly preferably 90% by mass or more, and most preferably 99.5% by mass or more.
• One embodiment of the acrylic resin (A) in the present invention is a homopolymer of methyl methacrylate, or the content of methyl methacrylate units in the acrylic resin (A) is 50% by mass or more and less than 100% by mass. More preferably 70% by mass or more and less than 100% by mass, still more preferably 80% by mass or more and less than 100% by mass, particularly preferably 90% by mass or more and less than 100% by mass, most preferably 99.5% by mass or more and less than 100% by mass.
• a certain methyl methacrylate copolymer hereinafter also referred to as "polymer (A1)" as appropriate
• polymer (A1) methyl methacrylate copolymer
• the polymer (A1) is a homopolymer of methyl methacrylate, or 50% by mass or more and less than 100% by mass, more preferably 70% by mass or more and less than 100% by mass, still more preferably 80% by mass or more and less than 100% by mass, especially Preferably 90% by mass or more and less than 100% by mass, most preferably 99.5% by mass or more and less than 100% by mass of methyl methacrylate units, and more than 0% by mass and less than 50% by mass, more preferably more than 0% by mass and less than 30% by mass % or less, more preferably more than 0% by weight and less than 20% by weight, particularly preferably more than 0% by weight and less than 10% by weight, most preferably more than 0% by weight and less than 0.5% by weight, copolymerized with methyl methacrylate. It is a methyl methacrylate copolymer containing repeating units (hereinafter referred to as "other monomer units”) derived from possible other monomers (hereinafter referred to as "other mono
• a homopolymer of methyl methacrylate is more preferable because it does not easily impair the inherent performance of the acrylic resin.
• Other monomers include, for example, methyl acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate.
• (meth)acrylate compounds other than methyl methacrylate are preferable because they do not impair the inherent performance of the acrylic resin, and methyl acrylate, Ethyl acrylate and n-butyl acrylate are more preferred, and methyl acrylate and ethyl acrylate are even more preferred.
• the content of the other monomeric units in 100% by mass of the polymer (A1) is less likely to impair the inherent performance of the acrylic resin. More than 50% by mass is preferable, more than 0% by mass is more preferably 30% by mass or less, more than 0% by mass is more preferably 20% by mass or less, and more than 0% by mass is 10% by mass or less. is particularly preferable, and more than 0% by mass and 0.5% by mass or less is most preferable.
• Examples of methods for producing the polymer (A1) include bulk polymerization, suspension polymerization, emulsion polymerization, and solution polymerization. Among these polymerization methods, the bulk polymerization method and the suspension polymerization method are preferable, and the bulk polymerization method is more preferable, because they are excellent in productivity.
• the mass average molecular weight of the acrylic resin (A) such as the polymer (A1) is less than 200,000, preferably 20,000 to 200,000, more preferably 50,000 to 150,000, and 50,000 to 100,000 is more preferred.
• the mass-average molecular weight of the acrylic resin (A) such as the polymer (A1) is 20,000 or more, the mechanical properties of the obtained resin molding are excellent.
• the mass average molecular weight of the acrylic resin (A) such as the polymer (A1) is less than 200,000, the fluidity during melt molding is excellent.
• the mass average molecular weights of the acrylic resin (A) and the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more described later are determined by gel permeation chromatography (GPC) using standard polystyrene as a standard sample.
• each of the acrylic resin (A) and the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more shall be the value measured using Instead of GPC measurement of each of the acrylic resin (A) and the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more, the acrylic resin (A) and the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more ), in the gel permeation chromatography elution curve, as the peak with the highest abundance, one in the region corresponding to the molecular weight of less than 200,000, the region corresponding to the molecular weight of 200,000 or more , each peak appears.
• the peak appearing in the molecular weight region of less than 200,000 corresponds to the molecular weight of the acrylic resin (A), and the peak appearing in the molecular weight region of 200,000 or more is the methacrylic polymer (C ) corresponds to the molecular weight of
• the lower limit of the content of the acrylic resin (A) in the total mass (100% by mass) of the methacrylic resin composition for injection molding or extrusion molding of the present invention is such that the obtained resin molded article has transparency, heat resistance and weather resistance. From the viewpoint of not impairing the original properties of the acrylic resin such as properties, it is preferably 55% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and particularly preferably 93% by mass or more.
• the upper limit of the content of the acrylic resin (A) is preferably 99% by mass or less, more preferably 98% by mass or less, and even more preferably 97% by mass or less, from the viewpoint of excellent scratch resistance of the resulting resin molded product. 96% by mass or less is particularly preferred.
• the content of the acrylic resin (A) in the total mass (100% by mass) of the methacrylic resin composition for injection molding or extrusion molding of the present invention is preferably 55% by mass or more and 99% by mass or less, and 70% by mass. 98 mass % or less is more preferable, 90 mass % or more and 97 mass % or less is still more preferable, and 93 mass % or more and 96 mass % or less is particularly preferable.
• Compound (B) containing at least one selected from fatty acids, fatty acid derivatives and fatty alcohols is one of the constituent components of the methacrylic resin composition of the present invention.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention contains at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols as the component (B), thereby reducing the viscosity of the molten resin. Further, by interacting with the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more, which will be described later, the scratch resistance of the obtained resin molding can be improved.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention comprises a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a methacrylic resin composition having a mass average molecular weight of 200,000 or more, which will be described later.
• a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols and a methacrylic resin composition having a mass average molecular weight of 200,000 or more, which will be described later.
• the lower limit of the content of the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols contained in the methacrylic resin composition for injection molding or extrusion molding of the present invention is the resin molded article obtained. From the viewpoint of excellent scratch resistance, it is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and further 0.2 parts by mass or more with respect to 100 parts by mass of the total mass of the acrylic resin (A). preferable.
• the upper limit of the content is preferably 10 parts by mass or less with respect to 100 parts by mass of the total mass of the acrylic resin (A), from the viewpoint that the obtained resin molded product does not impair the inherent performance of the acrylic resin, and 3.0 Part by mass is more preferable, and 1 part by mass or less is even more preferable.
• the above preferred upper limits and preferred lower limits can be combined arbitrarily.
• the content of the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols contained in the methacrylic resin composition for injection molding or extrusion molding of the present invention is the acrylic resin (A) With respect to the total mass of 100 parts by mass, preferably 0.01 parts by mass or more and 10 parts by mass or less, more preferably 0.1 parts by mass or more and 3.0 parts by mass or less, and 0.2 parts by mass or more and 1 part by mass or less preferable.
• the lower limit of the number of carbon atoms in the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols is excellent in compatibility with the acrylic resin (A), and the scratch resistance of the resulting resin molding is improved. From the viewpoint of being excellent, it is preferably 10 or more, more preferably 15 or more, and even more preferably 17 or more.
• the upper limit of the number of carbon atoms provides good dispersibility of the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols in the methacrylic resin composition for injection molding or extrusion molding.
• the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and fatty alcohols preferably has 10 to 25 carbon atoms, more preferably 15 to 24 carbon atoms, and more preferably 17 to 23 carbon atoms.
• fatty acid derivatives include fatty acid amides, fatty acid alkyls, fatty acid glycerides, etc. Among them, fatty acid amide compounds (hereinafter referred to as “fatty acid amide compounds (B-1)” as appropriate) are preferred.
• fatty acid amide compounds (B-1) include saturated fatty acid amide compounds, unsaturated fatty acid amide compounds, and bis-fatty acid amide compounds. These fatty acid amide compounds (B-1) may be used alone or in combination of two or more. Among these fatty acid amide compounds (B-1), saturated fatty acid amide compounds and unsaturated fatty acid amides are preferred, and saturated fatty acid amide compounds are more preferred, because the obtained resin molding has excellent scratch resistance.
• saturated fatty acid amide compounds include lauric acid amide, palmitic acid amide, stearic acid amide, and behenic acid amide. These saturated fatty acid amide compounds may be used alone or in combination of two or more. Among these saturated fatty acid amide compounds, at least one selected from stearic acid amide, palmitic acid amide, and behenic acid amide is preferable because the resulting resin molding has excellent scratch resistance.
• unsaturated fatty acid amides include erucic acid amide, oleic acid amide, brassic acid amide, and elaidic acid amide. These unsaturated fatty acid amide compounds may be used alone or in combination of two or more. Among these unsaturated fatty acid amide compounds, erucic acid amide and oleic acid amide are preferred, and erucic acid amide is more preferred, since the obtained resin molding has excellent scratch resistance.
• bis-fatty acid amide compounds include bis-fatty acid amides such as methylenebis-stearic acid amide, methylene-bis-oleic acid amide, ethylene-bis-stearic acid amide, and ethylene-bis-oleic acid amide; stearyl stearic acid amide, stearyl erucic acid amide, oleyl palmitin and acid amides. These bis-fatty acid amide compounds may be used singly or in combination of two or more.
• Stearamide is particularly preferred as the fatty acid amide compound (B-1).
• a fatty acid alkyl is a compound having a structure in which a fatty acid having about 10 to 22 carbon atoms and a monohydric aliphatic alcohol having about 1 to 10 carbon atoms are usually dehydrated and condensed.
• Examples of fatty acid alkyl include methyl laurate, ethyl laurate, butyl laurate, octyl laurate, methyl palmitate, ethyl palmitate, butyl palmitate, octyl palmitate, methyl stearate, ethyl stearate, and butyl stearate.
• octyl stearate methyl behenate, ethyl behenate, butyl behenate, saturated fatty acid alkyl such as octyl behenate; methyl oleate, ethyl oleate, butyl oleate, octyl oleate, methyl linoleate, ethyl linoleate, unsaturated fatty acid alkyl such as butyl linoleate and octyl linoleate; These fatty acid alkyl may be used individually by 1 type, and may use 2 or more types together. Among them, alkyl stearates such as methyl stearate, ethyl stearate, butyl stearate and octyl stearate are preferred, and methyl stearate is more preferred.
• a fatty acid glyceride is a compound having a structure in which a fatty acid having about 10 to 25 carbon atoms and glycerin are usually dehydrated and condensed.
• Fatty acid glycerides include fatty acid monoglycerides, fatty acid diglycerides, and fatty acid triglycerides.
• fatty acid glycerides include lauric acid monoglyceride, lauric acid diglyceride, lauric acid triglyceride, palmitic acid monoglyceride, palmitic acid diglyceride, palmitic acid triglyceride, stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, behenic acid monoglyceride, behenic acid.
• saturated fatty acid glycerides such as diglyceride and behenic acid triglyceride; unsaturated fatty acid glycerides such as oleic acid monoglyceride, oleic acid diglyceride, oleic acid triglyceride, linoleic acid monoglyceride, linoleic acid diglyceride, and linoleic acid triglyceride; These fatty acid glycerides may be used alone or in combination of two or more.
• stearic acid glycerides such as stearic acid monoglyceride, stearic acid diglyceride and stearic acid triglyceride are preferred, and stearic acid monoglyceride is more preferred.
• Aliphatic alcohol (hereinafter referred to as "fatty alcohol (B-2)" as appropriate) is usually an aliphatic alcohol (B-2) having 10 to 25 carbon atoms, and may be a monohydric alcohol. It may be a hydric alcohol. Specific examples of the fatty alcohol (B-2) include saturated fatty alcohols such as lauryl alcohol, palmityl alcohol, stearyl alcohol and behenyl alcohol; unsaturated fatty alcohols such as oleyl alcohol and linolyl alcohol; . These aliphatic alcohols (B-2) may be used alone or in combination of two or more. Among them, stearyl alcohol is preferred.
• fatty acid (B-3) The number of carbon atoms in the fatty acid (hereinafter referred to as “fatty acid (B-3)” as appropriate) is not particularly limited, but fatty acids having 10 to 25 carbon atoms can be preferably used.
• Specific examples of fatty acids (B-3) include saturated fatty acids such as lauric acid, palmitic acid, stearic acid, myristic acid and behenic acid; unsaturated fatty acids such as oleic acid and linoleic acid; . These fatty acids (B-3) may be used singly or in combination of two or more. Among these fatty acids (B-3), stearic acid, palmitic acid and myristic acid are preferred, and palmitic acid is more preferred.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention contains a methacrylic polymer (C) having a mass average molecular weight of 200,000 or more.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention contains an acrylic resin (A) having a mass average molecular weight of less than 200,000 and at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols.
• the coexistence of the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more of the component (C) causes the component (A) and the component (C) or the component (C) to become entangled. It becomes easy to match, and by creating a pseudo-crosslinking point, the brittleness of the molten resin can be improved.
• Component (C) is thus an additive for improving the brittleness of the molten resin. Therefore, by blending the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more, the scratch resistance of the resin molding obtained can be improved. In addition, since the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more is excellent in compatibility with the acrylic resin (A), the obtained resin molding has good transparency.
• the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more has excellent compatibility with the acrylic resin (A) having a mass average molecular weight of less than 200,000, the repeating unit derived from methyl methacrylate is added to 50 mass. % or more, more preferably 55 mass % or more, even more preferably 60 mass % or more, particularly preferably 65 mass % or more, most preferably 70 mass % or more.
• the content of methyl methacrylate units in the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more is 50.
• % by mass or more and less than 100% by mass more preferably 55% by mass or more and less than 100% by mass, still more preferably 60% by mass or more and less than 100% by mass, particularly preferably 65% by mass or more and less than 100% by mass, most preferably , and a methyl methacrylate copolymer (hereinafter also referred to as “polymer (C1)” as appropriate) having a content of 70% by mass or more and less than 100% by mass.
• a polymer (C1) containing 50% by mass or more of repeating units derived from methyl methacrylate is preferable because of its excellent compatibility with the acrylic resin (A).
• the mass average molecular weight of the polymer (C1) is preferably from 500,000 to 8,000,000, more preferably from 1,000,000 to 6,000,000.
• the mass average molecular weight of the polymer (C1) is 500,000 or more, the molded article has excellent scratch resistance.
• the mass average molecular weight of the polymer (C1) is 8,000,000 or less, the fluidity during melt molding is excellent.
• the polymer (C1) is preferably a linear polymer because it facilitates entanglement between the component (A) and the component (C) or between the components (C).
• the weight average molecular weight of the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more, such as the polymer (C1), is preferably 500,000 or more, more preferably 500,000 to 8,000,0000. ,000,000 to 6,000,000 are more preferred.
• the mass average molecular weight of the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more, such as the polymer (C1) is 500,000 or more, the resulting resin molded product has excellent chemical resistance.
• the weight average molecular weight of the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more, such as the polymer (C1) is 8,000,000 or less, the fluidity during melt molding is excellent.
• the content of the methacrylic polymer (C) having a weight average molecular weight of 200,000 or more in the methacrylic resin composition for injection molding or extrusion molding of the present invention is 0.00 per 100 parts by weight of the acrylic resin (A). 1 to 8 parts by mass is preferable, 0.5 to 5 parts by mass is more preferable, and 0.5 to 4.5 parts by mass is particularly preferable.
• the content of the methacrylic polymer (C) having a mass-average molecular weight of 200,000 or more is 0.1 parts by mass or more, molding defects can be suppressed, and the appearance of the obtained resin molding is excellent.
• the content of the methacrylic polymer (C) having a mass average molecular weight of 200,000 or more is 8 parts by mass or less, the fluidity during melt molding is excellent.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention has a ratio represented by [mass of component (C)]/[mass of component (B)], that is, [mass average molecular weight of 200,000 or more
• the mass of the methacrylic polymer (C)]/[the mass of the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols] is 50 or less.
• [mass of component (C)]/[mass of component (B)] is preferably 40 or less, more preferably 30 or less, still more preferably 10 or less, particularly 4.5 or less. is preferred.
• [mass of component (C)]/[mass of component (B)] is 0.01 or more, preferably 0.2 or more, more preferably 1 or more, further preferably 2 or more, particularly preferably 2.5 or more.
• the above preferred upper limits and preferred lower limits can be combined arbitrarily.
• [mass of component (C)]/[mass of component (B)] is in the range of 0.01 to 50, preferably 0.2 to 40, and more preferably 1 to 30. , more preferably 2 or more and 10 or less, and particularly preferably 2.5 or more and 4.5 or less.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention may or may not contain rubber particles (D) having a multilayer structure as component (D).
• the rubber particles (D) having a multi-layer structure can be blended as long as the content of the component (D) is in the range of more than 0 parts by mass and 15 parts by mass or less with respect to 100 parts by mass of the methacrylic resin composition. can.
• the content of the rubber particles (D) having a multi-layered structure is the content of the rubber particles (D) of the present invention, from the viewpoint of maintaining the effect of scratch resistance and transparency obtained by the combined use of the component (A), the component (B) and the component (C).
• methacrylic resin composition for injection molding or extrusion molding. It is preferably more than 0 parts by mass and 10 parts by mass or less, more preferably more than 0 parts by mass and 5 parts by mass or less, and more than 0 parts by mass and 3 parts by mass with respect to 100 parts by mass of the methacrylic resin composition for injection molding or extrusion molding.
• the following are more preferred, and it is particularly preferred that they are not included.
• the rubber particles (D) having a multilayer structure are components different from the components (A) and (C) described above.
• a known impact modifier can be used as the rubber particles (D) having a multi-layered structure. can be done.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention can contain carbon black (E). By blending carbon black (E), the jet-blackness of the obtained resin molding can be made more excellent.
• the carbon black (E) for example, the compatibility with the acrylic resin (A) is improved, and the dispersibility of the carbon black (E) in the methacrylic resin composition for injection molding or extrusion molding is improved.
• Carbon black coated with a surface coating agent is preferable from the viewpoint that the resulting resin molded article can exhibit a deeper jet-blackness.
• Examples of the surface coating agent include, but are not limited to, zinc stearate, magnesium stearate, calcium stearate, oleic acid amide, stearic acid amide, palmitic acid amide, methylenebisstearylamide, and ethylenebisstearylamide. One or more selected from among them are preferable. These surface coating agents may be used individually by 1 type, and may use 2 or more types together.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention may contain other additives in addition to the above-described components within a range that does not impair the performance of the resulting resin molding.
• additives include, for example, ultraviolet absorbers, anti-aging agents, light stabilizers, plasticizers, light diffusing agents, matting agents, lubricants, release agents, antistatic agents, fluidity modifiers, sliding colorants such as colorants such as colorants, pigments and dyes; These other additives may be used singly or in combination of two or more.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention comprises: an acrylic resin (A); a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols; 10,000 or more of the methacrylic polymer (C) and optionally other components can be mixed according to a conventional method, and the method is not particularly limited.
• each component for example, an acrylic resin (A), a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a methacrylic polymer having a mass average molecular weight of 200,000 or more
• a method of mixing the combination (C) and optionally other components in a single-screw extruder or a twin-screw extruder by heating and melt-kneading at about 220 to 280° C. can be mentioned.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention comprises a monomer mainly composed of methyl methacrylate, which is a raw material monomer of the acrylic resin (A), and a methacrylic resin composition having a mass average molecular weight of 200,000 or more.
• a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols can also be produced by a method of bulk polymerization.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention is prepared by pre-manufacturing acrylic resin (A) pellets and/or methacrylic polymer (C) pellets having a mass average molecular weight of 200,000 or more.
• the resin molded article of the present invention is a resin molded article obtained by molding the methacrylic resin composition for injection molding or extrusion molding of the present invention.
• Molding methods for obtaining the resin molded article of the present invention include injection molding and extrusion molding. Among them, injection molding is preferred.
• secondary molding such as air pressure molding or vacuum molding may be further performed on the obtained resin molding. Molding conditions such as molding temperature and molding pressure may be appropriately set.
• the resin molding of the present invention includes, for example, an acrylic resin (A), a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a methacrylic polymer having a mass average molecular weight of 200,000 or more.
• a methacrylic resin composition for injection molding or extrusion molding containing (C) can be obtained by appropriately setting the temperature of the extruder and mold during injection molding or extrusion molding.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention comprises a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a methacrylic polymer having a mass average molecular weight of 200,000 or more.
• (C) is blended into the acrylic resin (A) at a predetermined ratio, it is possible to obtain a resin molded product excellent in transparency, scratch resistance, etc. even at a mold temperature of 70 ° C. or less. can.
• the mold temperature during this molding can be, for example, 60 to 90.degree.
• the resin molded article of the present invention Since the resin molded article of the present invention has excellent scratch resistance, it can be used as vehicle members such as interior and exterior materials for vehicles such as tail lamp covers, head lamp covers, meter panels, pillar garnishes, front grills, and emblems; household equipment members such as washstands, bathtubs, and flush toilets; optical members such as lenses and light guides; containers for cosmetics and the like; and medical members such as cuvettes.
• vehicle members such as interior and exterior materials for vehicles such as tail lamp covers, head lamp covers, meter panels, pillar garnishes, front grills, and emblems
• household equipment members such as washstands, bathtubs, and flush toilets
• optical members such as lenses and light guides
• containers for cosmetics and the like and medical members such as cuvettes.
• ⁇ L* L*a*b* lightness difference in the color system
• Molding condition 1 Molding temperature: 240°C Mold temperature: 60°C Injection speed: 20mm/sec (transparency)
• a haze meter model name: HM-150L2N, Murakami Color Research Laboratory Co., Ltd.
• ⁇ total light transmittance of 90% or more and haze value of less than 1%
• ⁇ total light transmittance of less than 90%, or haze value of 1% or more
• Example 1 100 parts by mass of acrylic resin (A-1), 1.00 parts by mass of fatty acid amide compound (B-1) and 3.00 parts by mass of methacrylic polymer (C-1) having a mass average molecular weight of 200,000 or more are biaxially
• the mixture was supplied to an extruder (model name “PCM30”, manufactured by Ikegai Co., Ltd.) and kneaded at 250° C. to obtain a methacrylic resin composition for injection molding or extrusion molding in the form of pellets.
• the obtained methacrylic resin composition for injection molding or extrusion molding was evaluated for scratch resistance and transparency. Table 1 shows the results.
• Examples 2 to 9 Comparative Examples 1 to 3> A methacrylic resin composition in the form of pellets was obtained in the same manner as in Example 1 except that the formulations shown in Table 1 were used. Table 1 shows the evaluation results of the obtained methacrylic resin composition.
• the methacrylic resin compositions for injection molding or extrusion molding of Examples 1 to 9 contain component (A), component (B) and component (C), and [component (C)
• the value represented by [mass of component (B)]/[mass of component (B)] was 0.01 to 50, so that the resin molded product was excellent in scratch resistance and transparency regardless of the molding conditions.
• the methacrylic resin composition of Comparative Example 1 includes a compound (B) containing at least one selected from fatty acids, fatty acid derivatives and aliphatic alcohols, and a methacrylic polymer (C) having a mass average molecular weight of 200,000 or more.
• the acrylic resin (A) alone is used, and both the molding conditions 1 and 2 are inferior in scratch resistance.
• Comparative Example 2 does not contain the compound (B) containing at least one selected from fatty acids, fatty acid derivatives and fatty alcohols, and the scratch resistance is not sufficient under molding conditions 1 and 2.
• Comparative Example 3 does not contain a methacrylic polymer (C) having a mass average molecular weight of 200,000 or more, and excellent scratch resistance is obtained under molding condition 1, but poor scratch resistance is obtained under molding condition 2.
• the methacrylic resin composition for injection molding or extrusion molding of the present invention it is possible to obtain a resin molded article excellent in transparency and scratch resistance even at a mold temperature lower than 70°C. Since the resin molded article of the present invention is excellent in scratch resistance, it is used, for example, as materials for housing equipment such as bathroom vanities, bathtubs, and flush toilets; building materials; vehicle members such as interior and exterior materials for vehicles. is particularly suitable for vehicle members. Examples of vehicle exterior materials include meter covers, door mirror housings, pillar covers (sash covers), license garnishes, front grills, fog garnishes, and emblems.

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• 2022
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