WO2023132281A1 - Particules expansées à base de polypropylène et mousse moulée à base de polypropylène - Google Patents

Particules expansées à base de polypropylène et mousse moulée à base de polypropylène Download PDF

Info

Publication number
WO2023132281A1
WO2023132281A1 PCT/JP2022/047808 JP2022047808W WO2023132281A1 WO 2023132281 A1 WO2023132281 A1 WO 2023132281A1 JP 2022047808 W JP2022047808 W JP 2022047808W WO 2023132281 A1 WO2023132281 A1 WO 2023132281A1
Authority
WO
WIPO (PCT)
Prior art keywords
polypropylene
particles
weight
resin
expanded
Prior art date
Application number
PCT/JP2022/047808
Other languages
English (en)
Japanese (ja)
Inventor
豊 松宮
Original Assignee
株式会社カネカ
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社カネカ filed Critical 株式会社カネカ
Priority to JP2023572442A priority Critical patent/JPWO2023132281A1/ja
Publication of WO2023132281A1 publication Critical patent/WO2023132281A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/16—Making expandable particles
    • 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
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L23/10—Homopolymers or copolymers of propene

Definitions

  • the present invention relates to polypropylene-based foamed particles and polypropylene-based foamed molded articles.
  • Polypropylene-based foamed moldings are used in a variety of applications, including automobile interior parts, core materials for automobile bumpers, heat insulating materials, cushioning packaging materials, and returnable boxes.
  • polypropylene-based resin is a crystalline thermoplastic resin
  • non-crystalline thermoplastic resin such as polystyrene
  • polypropylene-based foamed molded articles obtained by molding polypropylene-based foamed particles are less likely to shrink after molding. is large. Therefore, in particular, when integrally molding other materials such as metal (insert molding), the metal member may be deformed due to shrinkage of the polypropylene-based foam molded body after molding. That is, in the prior art, it was difficult to control the dimensions and/or shape of the polypropylene-based foamed molded product, especially when other materials such as metal are integrally molded.
  • Patent Documents 1 and 2 disclose techniques for using a mixture of a polyolefin-based resin and a polystyrene-based resin.
  • an object of an embodiment of the present invention is to provide expanded polypropylene particles that can produce a polypropylene-based foamed molded article in which the occurrence of post-molding shrinkage and deformation is suppressed with good productivity.
  • the inventors of the present invention have completed the present invention as a result of intensive studies to solve the above problems.
  • one embodiment of the present invention includes the following configurations. 100 parts by weight of polypropylene resin, 5 parts by weight to 80 parts by weight of polystyrene resin, and 0.1 parts by weight to 15.0 parts by weight of nanoparticles, the nanoparticles having an average particle diameter per particle of 1,000 nm or less, and dispersed as aggregate-like particles having an average particle diameter of 3,000 nm or less.
  • polypropylene-based foamed particles that can provide a polypropylene-based foamed molded article in which the occurrence of shrinkage and deformation after molding is suppressed with good productivity.
  • FIG. 1 is a schematic diagram of a foam molded article 100 used for evaluation of the amount of deformation.
  • the structural units include a structural unit derived from the X1 monomer, a structural unit derived from the X2 monomer, ... and an Xn monomer (n is An integer of 2 or more) is also referred to as "X 1 /X 2 /.../X n copolymer".
  • the X 1 /X 2 /.../X n copolymer is not particularly limited in its polymerization mode unless otherwise specified, and may be a random copolymer or an alternating polymer. It may be a block copolymer or a graft copolymer.
  • X unit a structural unit derived from an X monomer contained in a polymer or copolymer
  • Patent Documents 1 and 2 there is known a method of suppressing shrinkage of a foam molded product by blending a polystyrene-based resin, which is an amorphous resin, with a polypropylene-based resin, which is a crystalline resin. ing. Polypropylene-based resin, which is a crystalline resin, and polystyrene-based resin, which is an amorphous resin, have low compatibility.
  • the present inventors developed a polypropylene-based foam-molded article in which the occurrence of post-molding shrinkage and deformation is suppressed (there is almost no post-molding shrinkage and deformation), and the water cooling time during molding is (in other words, it can be produced in a short molding cycle) by shortening the time required to provide expanded polypropylene particles.
  • aggregate particles having a predetermined average particle size and a predetermined average particle size were found in a mixture of a polypropylene resin, which is a crystalline resin, and a polystyrene resin, which is an amorphous resin.
  • the inventors have newly found that the above problems can be solved by adding a predetermined amount of dispersible nanoparticles.
  • the present inventors have found that agglomerate particles containing a polypropylene-based resin, a polystyrene-based resin, and a predetermined amount of nanoparticles having a predetermined average particle size, wherein the nanoparticles have a predetermined average particle size
  • the present inventors have found that the polypropylene-based foamed beads can shorten the water-cooling time during molding, compared with foamed beads containing a styrene-based thermoplastic elastomer, and the expanded beads can be molded in a shorter time (molding cycle). was found to be able to be molded.
  • the present inventors have found that a polypropylene-based foam molded article can be provided with good productivity, and have completed the present invention.
  • a foam molded product obtained by molding such polypropylene-based expanded particles can be suitably used for various uses as a foam molded product.
  • a foam molded product obtained by molding such polypropylene-based expanded particles can be suitably used for various uses as a foam molded product.
  • a relatively expensive styrene-based thermoplastic elastomer or even if the amount used is small, it is possible to provide a polypropylene-based foam-molded article that undergoes little shrinkage or deformation after molding. Therefore, it is possible to provide a polypropylene-based foamed molded article at a relatively low cost, which is economically advantageous.
  • nanoparticles having a predetermined average particle size are used, and the nanoparticles are dispersed as aggregate particles having a predetermined average particle size.
  • the polypropylene-based foamed particles according to one embodiment of the present invention contain 100 parts by weight of polypropylene-based resin, 5-80 parts by weight of polystyrene-based resin, and 0.1-30.0 parts by weight of nanoparticles.
  • the nanoparticles are expanded polypropylene particles dispersed as aggregate particles having an average particle size of 3000 nm or less.
  • a polypropylene-based expanded molded product can be provided by molding the polypropylene-based expanded particles according to one embodiment of the present invention by a known method.
  • polypropylene-based expanded beads may be referred to as “expanded beads”
  • polypropylene-based expanded beads according to one embodiment of the present invention may be referred to as “present expanded beads”
  • polypropylene system foam molded product is sometimes referred to as a “foam molded product”.
  • the polypropylene-based foamed particles according to one embodiment of the present invention have the above configuration, they have the advantage of being able to provide a polypropylene-based foamed molded article with little or no shrinkage or deformation after molding with good productivity. have. It can also be said that the polypropylene-based foamed particles according to one embodiment of the present invention can provide a polypropylene-based expanded molded article with reduced post-molding shrinkage and deformation compared to conventional products with high productivity.
  • the shrinkage of the foam molded article after molding is reduced is also referred to as "the foam molded article has excellent shrinkage suppression properties”.
  • “expanded particles capable of providing a foamed molded article in which shrinkage and deformation after molding are suppressed” may be referred to as “expanded particles exhibiting shrinkage suppression effect”.
  • the expanded particles contain a polypropylene-based resin.
  • the polypropylene-based resin intends a resin containing more than 50 mol % of structural units derived from a propylene monomer in 100 mol % of all structural units contained in the resin.
  • structural unit derived from propylene monomer may be referred to as "propylene unit”.
  • the polypropylene resin preferably contains 75 mol % or more of propylene units in 100 mol % of all structural units contained in the resin.
  • the polypropylene resin may be (a) a homopolymer of propylene, or (b) a block copolymer, alternating polymer, random copolymer or graft copolymer of propylene and a monomer other than propylene. or (c) a mixture of two or more thereof.
  • the polypropylene-based resin may have one or more structural units derived from a monomer other than the propylene monomer, or may have one or more types.
  • “Monomers other than propylene monomers” used in the production of polypropylene-based resins are sometimes referred to as "comonomers.”
  • a "structural unit derived from a monomer other than a propylene monomer" contained in a polypropylene-based resin may be referred to as a "comonomer unit".
  • Comonomers include ethylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3,4-dimethyl-1-butene, 1-heptene, Examples include ⁇ -olefins having 2 or 4 to 12 carbon atoms such as 3-methyl-1-hexene, 1-octene and 1-decene.
  • polypropylene resins include polypropylene homopolymers, ethylene/propylene random copolymers, 1-butene/propylene random copolymers, 1-butene/ethylene/propylene random copolymers, and ethylene/propylene block copolymers. coalescence, 1-butene/propylene block copolymer, propylene/chlorinated vinyl copolymer, propylene/maleic anhydride copolymer, styrene-modified polypropylene resin and the like. As the polypropylene-based resin, one of these may be used alone, or two or more thereof may be used in combination.
  • ethylene/propylene random copolymers and 1-butene/ethylene/propylene random copolymers have good expandability in the resulting expanded beads, It is suitable because the body has good moldability.
  • the 1-butene is synonymous with butene-1.
  • ethylene/propylene random copolymer or a 1-butene/ethylene/propylene random copolymer is used as the polypropylene resin (Case A).
  • the ethylene content in the ethylene/propylene random copolymer or 1-butene/ethylene/propylene random copolymer is 0.2% to 10.0% by weight based on 100% by weight of each copolymer. is preferred.
  • the ethylene content can also be said to be the content of structural units (ethylene units) derived from ethylene.
  • the content of ethylene units in the ethylene/propylene random copolymer or the 1-butene/ethylene/propylene random copolymer is (i) 0.2% by weight or more, The foamability and/or the moldability of the resulting expanded beads tend to be improved, and (ii) when the content is 10.0% by weight or less, the mechanical properties of the expanded molded article obtained from the present expanded beads are reduced. No fear.
  • the 1-butene content in the 1-butene/ethylene/propylene random copolymer is preferably 0.2 wt% to 10.0 wt% in 100 wt% of the copolymer.
  • the 1-butene content can also be said to be the content of structural units (1-butene units) derived from 1-butene.
  • the content of 1-butene units in the 1-butene/ethylene/propylene random copolymer is (i) 0.2% by weight or more, the expandability of the expanded beads in the production of the expanded beads and/or The moldability of the resulting expanded beads tends to be good, and (ii) when the content is 10.0% by weight or less, there is no possibility that the mechanical properties of the expanded molded article obtained from the present expanded beads are deteriorated.
  • the total content of ethylene units and 1-butene units in the 1-butene/ethylene/propylene random copolymer is 0 in 100% by weight of the 1-butene/ethylene/propylene random copolymer. 0.5% to 10.0% by weight is preferred.
  • the total content of ethylene units and 1-butene units in the 1-butene/ethylene/propylene random copolymer is (i) 0.5% by weight or more, the expandability of the expanded beads in the production of the present expanded beads and/or the moldability of the resulting expanded beads tends to be good, and (ii) when the content is 10.0% by weight or less, the mechanical properties of the expanded molded article obtained from the present expanded beads may deteriorate. do not have.
  • the melting point of the polypropylene resin is preferably 135.0°C to 160.0°C, more preferably 138.0°C to 158.0°C, more preferably 140.0°C to 156.0°C, and 143.0°C. ⁇ 154.0°C is more preferred, 145.0°C to 152.0°C is even more preferred, and 148.0°C to 150.0°C is particularly preferred.
  • the melting point of the polypropylene-based resin is (i) 135.0°C or higher, the foamed molded article obtained from the present expanded beads has excellent heat resistance, and (ii) when it is 160.0°C or lower, the present It becomes easy to increase the expansion ratio of the expanded beads in the production of the expanded beads.
  • the melting point of a polypropylene-based resin is a value obtained by measuring with a differential scanning calorimeter method (hereinafter referred to as "DSC method").
  • DSC method differential scanning calorimeter method
  • the specific operating procedure is as follows: (1) By raising the temperature of 5 mg to 6 mg of polypropylene resin from 40.0° C. to 220.0° C. at a rate of 10.0° C./min. (2) Then, the polypropylene resin is lowered from 220.0°C to 40.0°C at a rate of 10.0°C/min. (3) Then, the temperature of the crystallized polypropylene-based resin is further increased from 40.0°C to 220.0°C at a rate of temperature increase of 10°C/min.
  • the temperature of the peak (melting peak) of the DSC curve of the polypropylene-based resin obtained during the second heating can be obtained as the melting point of the polypropylene-based resin.
  • the temperature of the peak (melting peak) with the maximum amount of heat of fusion is It is the melting point of the system resin.
  • the differential scanning calorimeter for example, DSC6200 type manufactured by Seiko Instruments Inc. can be used.
  • the melt index (MI) of the polypropylene resin is not particularly limited, but is preferably 3.0 g/10 minutes to 30.0 g/10 minutes, more preferably 4.0 g/10 minutes to 20.0 g/10 minutes, 5.0 g/10 minutes to 15.0 g/10 minutes is more preferable, and 6.0 g/10 minutes to 13.0 g/10 minutes is particularly preferable.
  • MI may also be referred to as "melt flow rate (MFR)".
  • the MI of the polypropylene-based resin When the MI of the polypropylene-based resin is 3.0 g/10 minutes or more, it becomes easy to increase the expansion ratio of the expanded beads in the production of the present expanded beads. When the MI of the polypropylene-based resin is 30.0 g/10 minutes or less, there is no possibility that the cells of the expanded beads obtained will be communicated, and as a result, (i) compression of the expanded molded article formed by molding the present expanded beads The strength tends to be good, and/or (ii) the surface properties of the foamed molded product obtained by molding the present expanded beads tends to be good.
  • the value of MI of a polypropylene resin is a value obtained by measuring under the following conditions using an MI measuring instrument described in JIS K7210: 1999: the diameter of the orifice is 2.0959 ⁇ 0. .005 mm ⁇ , orifice length of 8.000 ⁇ 0.025 mm, load of 2.16 kgf, and temperature of 230° C. (230 ⁇ 0.2° C.).
  • Polypropylene-based resin can be obtained by a known method.
  • the polymerization catalyst for synthesizing the polypropylene-based resin is not particularly limited, and for example, Ziegler-based catalysts and metallocene catalysts can be used.
  • the density of the polypropylene-based resin is not particularly limited, but is preferably 0.87 g/cm 3 to 0.93 g/cm 3 , more preferably 0.88 g/cm 3 to 0.92 g/cm 3 , and more preferably 0.89 g/cm 3 to 0.92 g/cm 3 . More preferably cm 3 to 0.91 g/cm 3 .
  • the density of the polypropylene-based resin is within the above range, there is an advantage that both the moldability of the expanded beads and the strength of the resulting expanded molded article can be achieved.
  • the polypropylene-based resin is a mixture of a plurality of types of copolymers, the density of the polypropylene-based resin intends the density of the mixture.
  • polystyrene resin The foamed particles contain 5 to 80 parts by weight of a polystyrene-based resin with respect to 100 parts by weight of a polypropylene-based resin. Note that the polystyrene resin is an amorphous resin.
  • the polystyrene-based resin means a resin containing 20% by weight or more of structural units derived from styrene-based monomers out of 100% by weight of all structural units contained in the resin.
  • the "structural unit derived from a styrene-based monomer” may be referred to as a "styrene-based unit".
  • a resin containing more than 50 mol% of propylene units in 100 mol% of the total structural units contained in the resin is a polystyrene resin even if it contains 20% by weight or more of styrene units. don't see Moreover, a styrene-based thermoplastic elastomer, which will be described later, is also not regarded as a polystyrene-based resin.
  • the polystyrene resin may be (a) a homopolymer of one styrene monomer, or (b) a block copolymer, alternating copolymer, or random copolymer of two or more styrene monomers. It may be a copolymer or a graft copolymer, and (c) a block copolymer or an alternating copolymer of at least one styrene-based monomer and at least one monomer other than a styrene-based monomer. , a random copolymer or a graft copolymer, or (d) a mixture of two or more thereof.
  • Styrenic monomers include, for example, (a) styrene, and (b) ⁇ -methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, 2,4-dimethylstyrene, p-ethyl Styrene derivatives such as styrene, m-ethylstyrene, o-ethylstyrene, t-butylstyrene, and chlorostyrene.
  • styrene and ⁇ -methylstyrene are preferred because they have the advantage of being able to provide expanded particles exhibiting good foamability and a good effect of suppressing shrinkage.
  • These styrenic monomers may be used singly or in combination of two or more. That is, the styrenic units contained in the polystyrene-based resin may be of one type or a combination of two or more types.
  • Examples of monomers other than styrene-based monomers include acrylonitrile; vinyl esters such as vinyl acetate and vinyl propionate; acrylic acid esters such as methyl acrylate and ethyl acrylate; methacrylic acid such as methyl methacrylate and ethyl methacrylate. Esters; Olefins such as ethylene and propylene; Maleic anhydride; Vinyl chloride; Vinylidene chloride; , 4-ethyl-1,3-hexadiene; and monomers copolymerizable with other styrenic monomers. These monomers other than styrene-based monomers may be used singly or in combination of two or more.
  • the amount of styrene units contained in the polystyrene resin is 20% by weight or more, preferably 30% by weight or more, more preferably 40% by weight or more, and even more preferably 50% by weight or more, based on 100% by weight of the polystyrene resin. . If the amount of styrene-based units contained in the polystyrene-based resin is within the above range, it is possible to provide expanded beads exhibiting a good shrinkage-suppressing effect, and to obtain a foam-molded article in which the occurrence of post-molding shrinkage and deformation is further suppressed. can provide.
  • the upper limit of the amount of styrene-based units in the polystyrene-based resin is not particularly limited, and may be 100% by weight. That is, the polystyrene-based resin may be composed only of styrene-based units.
  • the amount of structural units derived from a monomer other than a styrene-based monomer contained in the polystyrene-based resin is 80% by weight or less, preferably 70% by weight or less, and 60% by weight in 100% by weight of the polystyrene-based resin. The following is more preferable, and 50% by weight or less is even more preferable. If the amount of structural units derived from a monomer other than a styrene-based monomer contained in the polystyrene-based resin is within the above range, it is possible to provide expanded beads exhibiting a favorable effect of suppressing shrinkage, and to prevent shrinkage after molding. It is possible to provide a foam molded article in which the occurrence of deformation is further suppressed.
  • polystyrene resins include polystyrene homopolymer; acrylonitrile/styrene copolymer, acrylonitrile/ ⁇ -methylstyrene copolymer, acrylonitrile/p-methylstyrene copolymer, acrylonitrile/m-methylstyrene copolymer.
  • acrylonitrile/o-methylstyrene copolymer acrylonitrile/2,4-dimethylstyrene copolymer, acrylonitrile/p-ethylstyrene copolymer, acrylonitrile/m-ethylstyrene copolymer, acrylonitrile/o-ethylstyrene copolymer
  • Polymers acrylonitrile/t-butylstyrene copolymers, and copolymers containing acrylonitrile units and styrenic units such as acrylonitrile/chlorostyrene copolymers; ethylene/styrene copolymers; styrene/maleic anhydride copolymers ; and the like.
  • polystyrene-based resin one of these may be used alone, or two or more thereof may be used in combination.
  • polystyrene homopolymers and copolymers containing acrylonitrile units and styrenic units are preferable because they can provide foamed particles having excellent foamability and exhibiting a good effect of suppressing shrinkage.
  • the polystyrene-based resin contained in the expanded beads is preferably one or more selected from the group consisting of polystyrene homopolymers and copolymers containing acrylonitrile units and styrene-based units.
  • the glass transition temperature (sometimes referred to as "Tg") of the polystyrene resin is not particularly limited, but is preferably 90°C to 140°C, more preferably 95°C to 135°C, and further preferably 97°C to 130°C. 100° C. to 125° C. is particularly preferred.
  • Tg glass transition temperature
  • the Tg of the polystyrene-based resin is (i) 90° C. or higher, there is an advantage that it is possible to obtain expanded beads and a foamed molded article having excellent heat resistance. It is possible to obtain expanded particles with a low porosity.
  • the Tg of a polystyrene resin is a value obtained by measuring in accordance with JIS-K-7121 using a differential scanning calorimeter [Model DSC6200, manufactured by Seiko Instruments Inc.]. Specific operating procedures are as follows (1) to (5): (1) Weigh 5 mg of polystyrene resin; (3) The temperature of the polystyrene resin is lowered from 250° C. to room temperature at 10° C./min; (4) Again, the temperature of the polystyrene resin is reduced by 10 The temperature is raised from room temperature to 250 ° C. at a rate of ° C./min; Tg of the system resin.
  • the melt index (MI) of the polystyrene resin is not particularly limited, but is preferably 2.0 g/10 minutes to 15.0 g/10 minutes, more preferably 3.0 g/10 minutes to 12.0 g/10 minutes, 4.0 g/10 minutes to 10.0 g/10 minutes is more preferable.
  • Polystyrene resins with an MI in the range of 2.0 g/10 minutes to 15.0 g/10 minutes have excellent compatibility with polypropylene resins, and reduce open cells when the resulting resin particles are expanded. can. As a result, there is an advantage that expanded beads having a low open cell ratio can be obtained.
  • the MI of the polystyrene-based resin intends the MI of the mixture.
  • the MI value of a polystyrene resin is a value obtained by measuring under the following conditions using an MI measuring instrument described in JIS K7210: 1999: the diameter of the orifice is 2.0959 ⁇ 0.005 mm ⁇ , orifice length of 8.000 ⁇ 0.025 mm, load of 2.16 kgf, and temperature of 230° C. (230 ⁇ 0.2° C.).
  • the content of the polystyrene resin in the expanded beads is 5 parts by weight to 80 parts by weight, more preferably 5 parts by weight to 70 parts by weight, and 8 parts by weight to 50 parts by weight with respect to 100 parts by weight of the polypropylene resin. 15 parts by weight to 35 parts by weight is more preferred, and 20 parts by weight to 30 parts by weight is particularly preferred.
  • the content of the polystyrene-based resin is (a) 5 parts by weight or more with respect to 100 parts by weight of the polypropylene-based resin, it is possible to provide a foamed molded article with reduced shrinkage and deformation after molding, and (b ) is 80 parts by weight or less, it has the advantage of being able to provide foamed beads with a low open cell ratio.
  • Nanoparticles The foamed particles contain 0.1 to 30.0 parts by weight of nanoparticles with respect to 100 parts by weight of the polypropylene resin.
  • nanoparticles mean particulate substances having an average particle size of 1000 nm or less per particle.
  • the present inventors have found that some or all of the nanoparticles contained in the foamed particles are aggregate-like particles composed of a plurality of primary particles (single particles) of nanoparticles aggregated, and polypropylene It has been newly discovered that it can be dispersed in a base resin consisting of a polystyrene resin and a polystyrene resin. Further, by molding expanded beads in which aggregate particles of nanoparticles dispersed in the base resin have an average particle size of 3000 nm or less, it is possible to provide a foamed molded article in which the occurrence of deformation and shrinkage is suppressed. also newly found. That is, in the expanded beads, the nanoparticles are dispersed as aggregate particles having an average particle diameter of 3000 nm or less.
  • the term “aggregate particles” means particles (secondary particles) formed by aggregating primary particles (single particles) of a plurality of nanoparticles.
  • “dispersed” means that the primary particles of the aggregate-like particles and/or nanoparticles are independent of each other (not in contact with each other) in the base resin made of polypropylene resin and polystyrene resin. intended to exist. Therefore, the present expanded beads can also be said to be expanded beads in which the primary particles of the aggregate-like particles and/or nanoparticles are dispersed in a base resin composed of a polypropylene-based resin and a polystyrene-based resin.
  • the state of the nanoparticles in the expanded beads can be confirmed, for example, by observing the cross section of the expanded beads using a transmission electron microscope (TEM).
  • TEM transmission electron microscope
  • the term "aggregate-like particles” refers to particles substantially composed of primary particles of nanoparticles. are not regarded as “aggregate-like particles” even if they contain primary particles of
  • the nanoparticles contained in the foamed beads are (1) all nanoparticles may be dispersed in the form of aggregated particles, and (2) the nanoparticles may be dispersed in the form of a mixture of aggregated particles and primary particles. You may have
  • nanoparticles include carbon black, calcium carbonate (CaCO 3 ), kaolin, activated carbon, zeolite, titania, magnesia, and carbon nanotubes.
  • One type of these nanoparticles may be used alone, or two or more types may be used in combination.
  • the nanoparticles are preferably one or more selected from the group consisting of carbon black, calcium carbonate and kaolin, since they are relatively inexpensive and have the advantage of being highly compatible with the base resin. preferable.
  • calcium carbonate may be either surface-treated calcium carbonate or non-surface-treated calcium carbonate. Note that talc is not considered a nanoparticle according to one embodiment of the present invention, even if the particle size is 1000 nm or less.
  • the average particle size of the aggregated particles is 3000 nm or less, preferably 2000 nm or less, more preferably 1500 nm or less, and even more preferably 1000 nm or less.
  • the aggregate particles may have an average particle size of 500 nm or less. If the average particle diameter of the agglomerate-like particles contained in the foamed particles is 3000 nm or less, it is possible to provide a foamed molded article with reduced shrinkage and deformation after molding.
  • the lower limit of the average particle size of the aggregated particles is not particularly limited, it may be, for example, 10 nm or more.
  • the average particle size of the aggregate particles means "number average particle size" and is a value measured by the method described in Examples.
  • the shape of the aggregated particles is not particularly limited, and may be spherical, approximately spherical, irregular, or the like.
  • the average particle size per nanoparticle (primary particle) is not particularly limited as long as it is 1000 nm or less, but is preferably 900 nm or less, more preferably 800 nm or less, and further preferably 700 nm or less. It is preferably 600 nm or less, particularly preferably less than 500 nm, and most preferably 300 nm or less.
  • the average particle size per nanoparticle (primary particle) is less than 500 nm, the compatibility between the polypropylene-based resin and the polystyrene-based resin can be improved, and expanded particles exhibiting a better effect of suppressing shrinkage can be provided. There is an advantage.
  • the lower limit of the average particle size of the nanoparticles is not particularly limited, it can be, for example, 100 nm or more.
  • the shape of the primary particles of the nanoparticles is not particularly limited, and may be spherical or approximately spherical.
  • the content of the nanoparticles in the expanded beads is 0.1 to 15.0 parts by weight, more preferably 0.1 to 13.0 parts by weight, with respect to 100 parts by weight of the polypropylene resin. , more preferably 0.1 to 10.0 parts by weight, even more preferably 0.1 to 5.0 parts by weight, and particularly preferably 0.1 to 1.0 parts by weight.
  • Expanded particles having a nanoparticle content within the above range can provide a foamed molded product with reduced shrinkage and deformation after molding.
  • the expanded particles may contain a styrenic thermoplastic elastomer.
  • the styrenic thermoplastic elastomer means (i) a block polymer (styrene block) composed of styrene (styrene units), and (ii) (ii-a) an unsaturated polymer such as polybutylene or polyisoprene.
  • the styrenic thermoplastic elastomer comprises (i) a hard segment composed of styrene units and (ii) a soft segment composed of diene (conjugated diene) units and/or structural units obtained by hydrogenating diene (conjugated diene) units. It can also be said that it is a copolymer having segments.
  • the number of styrene blocks in the styrene-based thermoplastic elastomer is not particularly limited, and may be two or more.
  • the number of block polymers composed of diene (conjugated diene) units and/or structural units obtained by hydrogenating the diene (conjugated diene) units is not particularly limited. There may be more than one.
  • styrene-based thermoplastic elastomers include styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-butylene-styrene block copolymer (SEBS).
  • SBS styrene-butadiene-styrene block copolymer
  • SIS styrene-isoprene-styrene block copolymer
  • SEBS styrene-ethylene-butylene-styrene block copolymer
  • styrene-ethylene-propylene-styrene block copolymer SEPS
  • SEEPS styrene-ethylene-ethylene-propylene-styrene block copolymer
  • SBBS styrene-butadiene-butylene-styrene block copolymer
  • styrene - Hydrogenated styrene-butadiene block copolymers such as butadiene diblock copolymers, styrene/ethylene/butylene/styrene block copolymers (SEBS), styrene/ethylene/propylene/styrene block copolymers (SEPS), hydrogenated Styrene-isoprene block copolymers, hydrogenated styrene-butadiene random copolymers, and the like.
  • SEBS styrene/ethylene/butylene/styrene block copolymers
  • SEPS
  • a styrene-based thermoplastic elastomer can be said to be a compatibilizer because it has a compatibilizing effect between a polypropylene-based resin and a polystyrene-based resin. If the foamed particles contain an excessive amount of the styrene-based thermoplastic elastomer, the productivity of the foam-molded article may decrease and the production cost may increase. Therefore, the content of the styrene-based thermoplastic elastomer in the present foamed particles is 10 parts per 100 parts by weight of the polypropylene-based resin, from the viewpoint of providing a foamed molded article with excellent productivity and at a low cost (price).
  • the lower limit of the amount of the styrene-based thermoplastic elastomer in the expanded beads is not particularly limited, and may be 0 parts by weight.
  • the foamed particles preferably do not contain a styrenic thermoplastic elastomer, since a foamed molded article can be provided at a lower cost.
  • the foamed particles do not contain a styrene-based thermoplastic elastomer, or contain a styrene-based thermoplastic elastomer in an amount of more than 0 to 10 parts by weight with respect to 100 parts by weight of the polypropylene resin.
  • the expanded beads may further contain resins other than polypropylene-based resins and polystyrene-based resins (sometimes referred to as other resins, etc.) as resin components within a range that does not impair the effects of the present invention.
  • the other resins include (a) high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, linear ultra-low-density polyethylene, ethylene/vinyl acetate copolymer, ethylene/acrylic acid.
  • Ethylene-based resins such as copolymers and ethylene/methacrylic acid copolymers
  • polyphenylene ether-based resins such as polyphenylene ether and modified polyphenylene ether
  • polyolefin-based waxes such as propylene/ ⁇ -olefin-based waxes
  • olefinic rubbers such as ethylene/propylene rubber, ethylene/butene rubber, ethylene/hexene rubber and ethylene/octene rubber.
  • the polyphenylene ether-based resin is an amorphous resin.
  • the content of other resins, etc. in the expanded beads is preferably 0.1 to 20.0 parts by weight, more preferably 0.5 to 15.0 parts by weight, with respect to 100 parts by weight of the polypropylene resin. More preferably 1.0 to 10.0 parts by weight, even more preferably 3.0 to 8.0 parts by weight.
  • the expanded beads containing the other resins within the above range are advantageous in that the moldability, the effect of suppressing shrinkage, and the strength of the resulting expanded molded product are well balanced.
  • the foamed particles may optionally contain additives in addition to the polypropylene-based resin, the polystyrene-based resin, and the nanoparticles.
  • Additives include coloring agents, hydrophilic compounds, crystal nucleating agents, antistatic agents, flame retardants, antioxidants, light stabilizers, crystal nucleating agents, conductive agents, lubricants, and the like.
  • Such additives may be used during the production of the resin particles and incorporated into the resin particles in the production of the present expanded beads, or may be added directly to the dispersion liquid in the expansion step described later.
  • even substances of the same type as the nanoparticles described above, but having an average particle diameter of more than 1000 nm per particle are not considered nanoparticles according to an embodiment of the present invention. , can be used separately as an additive.
  • a hydrophilic compound is a substance used for the purpose of increasing the amount of impregnated water in the resin particles in the production of the expanded beads. By using a hydrophilic compound when producing the present expanded beads, it is possible to impart expandability to the resin beads. The effect of imparting expandability to the resin particles by the hydrophilic compound is particularly remarkable when water is used as the blowing agent.
  • Hydrophilic compounds that can be used in one embodiment of the present invention include, for example, glycerin, diglycerin, polyethylene glycol, aliphatic alcohols having 12 to 18 carbon atoms (eg, pentaerythritol, cetyl alcohol, stearyl alcohol, ), melamine, isocyanuric acid, melamine/isocyanuric acid condensate, zinc borate and the like.
  • glycerin diglycerin
  • polyethylene glycol aliphatic alcohols having 12 to 18 carbon atoms (eg, pentaerythritol, cetyl alcohol, stearyl alcohol, ), melamine, isocyanuric acid, melamine/isocyanuric acid condensate, zinc borate and the like.
  • aliphatic alcohols having 12 to 18 carbon atoms eg, pentaerythritol, cetyl alcohol, stearyl alcohol,
  • melamine isocyanuric acid
  • Glycerin and polyethylene glycol (a) do not promote miniaturization of the average cell diameter of expanded particles, and (b) have good affinity with polypropylene resins. Therefore, among the hydrophilic compounds mentioned above, glycerin and/or polyethylene glycol are preferred.
  • the amount of the hydrophilic compound used in the production of the expanded beads in other words, the content of the hydrophilic compound in the expanded beads will be explained.
  • the content of the hydrophilic compound in the expanded beads is preferably 0.01 to 1.00 parts by weight, more preferably 0.05 to 0.70 parts by weight, with respect to 100 parts by weight of the polypropylene resin. and more preferably 0.10 to 0.60 parts by weight.
  • the content of the hydrophilic compound is (i) 0.01 parts by weight or more, the effect of imparting foamability by the hydrophilic compound can be sufficiently obtained, and (ii) when it is 1.00 parts by weight or less, There is no danger that the resulting expanded beads will shrink excessively.
  • a crystal nucleating agent is a substance that can be used in the production of the present foamed beads and that can serve as foaming nuclei when the resin beads are foamed.
  • a crystal nucleating agent is preferably used in the production of the present expanded beads, in other words, the present expanded beads preferably contain a crystal nucleating agent.
  • Crystal nucleating agents that can be used in one embodiment of the present invention include, for example, substances having an average (primary) particle size of more than 1000 nm per particle (e.g., talc, feldspar, zeolite, kaolin, mica, calcium stearate, carbonate calcium, silica, titanium oxide, bentonite, barium sulfate, zinc borate, etc.).
  • substances having an average (primary) particle size of more than 1000 nm per particle e.g., talc, feldspar, zeolite, kaolin, mica, calcium stearate, carbonate calcium, silica, titanium oxide, bentonite, barium sulfate, zinc borate, etc.
  • One type of these crystal nucleating agents may be used alone, or two or more types may be mixed and used.
  • the mixing ratio may be appropriately adjusted according to the purpose.
  • the amount of the crystal nucleating agent used in the production of the expanded beads in other words, the content of the crystal nucleating agent in the expanded beads will be explained.
  • the content of the crystal nucleating agent in the expanded beads is preferably 0.01 to 2.00 parts by weight, preferably 0.02 parts by weight, with respect to 100 parts by weight of the polypropylene-based resin, from the viewpoint of uniformity of the average cell diameter. parts to 1.00 parts by weight is more preferred, and 0.03 parts to 0.50 parts by weight is even more preferred.
  • the expanded beads preferably have an expansion ratio of 10.0 to 50.0 times, more preferably 11.0 to 40.0 times, and 13.0 to 25.0 times. is more preferable, and 15.0 times to 20.0 times is particularly preferable.
  • the expansion ratio of the expanded particles is (i) 10.0 times or more, a lightweight foamed molded article can be obtained with good production efficiency, and (ii) when it is 50.0 times or less, the obtained expanded molded article is obtained. There is no fear that the strength of will be insufficient.
  • the expanded beads preferably have at least two melting peaks in a DSC curve obtained by differential scanning calorimetry, which will be described later.
  • the heat of fusion obtained from the melting peak on the high temperature side is referred to as the "heat of fusion on the high temperature side”
  • the heat of fusion obtained from the melting peak on the low temperature side is referred to as the "heat of fusion on the low temperature side”.
  • the heat of fusion obtained from the highest melting peak is defined as the "heat of fusion on the high temperature side”
  • the heat of fusion obtained from the other melting peaks is defined as the heat of fusion on the low temperature side.
  • the DSC ratio of the present expanded beads is not particularly limited, it is preferably 10.0% to 50.0%, more preferably 20.0% to 40.0%, and 22.0% to 30%. 0% is more preferred.
  • the DSC ratio of the expanded beads is 10.0% or more, there is an advantage that the expanded molded article obtained by molding the expanded beads has sufficient strength.
  • the DSC ratio of the expanded beads is 50.0% or less, there is an advantage that the expanded beads can be molded at a relatively low molding temperature.
  • the DSC ratio means the ratio of the heat of fusion on the high temperature side to the total heat of fusion calculated from the DSC curve of the expanded beads.
  • the DSC curve is obtained using a differential scanning calorimeter (eg DSC6200 manufactured by Seiko Instruments Inc.). More specifically, in the present specification, the method of measuring (calculating) the DSC ratio of expanded beads using a differential scanning calorimeter (for example, DSC6200 manufactured by Seiko Instruments Inc.) is as follows (1) to (5). (1) Weigh 5 mg to 6 mg of the expanded beads; (2) Increase the temperature of the expanded beads from 40° C. to 220° C.
  • the DSC ratio of the expanded beads is also a value that serves as a guideline for the amount of crystals with a high melting point contained in the expanded beads. That is, the fact that the DSC ratio of the expanded beads is 10.0% to 50.0% indicates that the expanded beads contain a relatively large amount of crystals with a high melting point. Further, the DSC ratio of the expanded beads is greatly related to the viscoelasticity of the resin beads and the expanded beads when the resin beads are expanded and when the expanded beads are expanded. That is, when the DSC ratio of the expanded beads is 10.0% to 50.0%, the resin beads and the expanded beads have excellent expandability when the resin beads are expanded and when the expanded beads are molded. and expandable. As a result, the expanded beads having a DSC ratio of 10.0% to 50.0% can provide a foamed molded article having excellent internal fusion bondability and excellent mechanical strength such as compressive strength at a low molding pressure. has the advantage of
  • the conditions at the time of production of the present expanded beads in particular, the expansion temperature, expansion pressure, holding time, and temperature of the area (space) where the dispersion liquid is released etc.).
  • the method for controlling the DSC ratio within a predetermined range the method of adjusting the foaming temperature, foaming pressure and/or holding time is preferable because of the ease of adjustment.
  • the DSC ratio of the obtained expanded beads tends to decrease, and conversely, when the foaming temperature is decreased, the DSC ratio of the obtained expanded beads tends to increase.
  • the amount of unmelted crystals contained in the expanded beads varies depending on the expansion temperature.
  • the expansion pressure changes the degree of plasticization, which in turn changes the amount of unmelted crystals contained in the expanded beads.
  • the longer the holding time the higher the DSC ratio of the resulting expanded beads. This is because the growth amount of unmelted crystals contained in the foamed beads changes depending on the holding time.
  • the open cell ratio of the expanded beads is preferably as low as possible.
  • the open cell rate of the expanded beads is preferably 15.0% or less, more preferably 10.0% or less, more preferably 9.0% or less, and 8.0% or less. more preferably 7.0% or less, more preferably 6.0% or less, more preferably 5.0% or less, and 4.0% or less is more preferred.
  • the lower limit of the open cell content of the expanded beads is not particularly limited, and is, for example, 0.0% or more. According to this configuration, (a) when the expanded beads are molded, the cells hardly break and shrink, so that the expanded beads have excellent moldability, and (b) the obtained by using the expanded beads.
  • the resulting foamed molded product has the advantage of exhibiting more features such as shape arbitrariness, cushioning properties, lightness, compressive strength and heat insulating properties.
  • the open cell ratio of the expanded beads can be controlled by, for example, the amount of acrylonitrile/styrene copolymer used.
  • the open cell ratio of the foamed particles is measured using an air-comparative hydrometer [manufactured by Tokyo Science Co., Ltd., model 1000], according to the method described in ASTM D2856-87 procedure C (PROSEDURE C). It is a value obtained by measurement.
  • the open cell ratio of the expanded beads is calculated by performing the following (1) to (4) in order: (1) Volume Vc (cm 3 ) of the expanded beads using an air-comparative hydrometer.
  • the present method for producing expanded beads includes a step of expanding polypropylene-based resin particles to form expanded beads, and the polypropylene-based resin particles are composed of 100 parts by weight of polypropylene-based resin and 5 to 80 parts by weight of polystyrene-based resin. and 0.1 to 15.0 parts by weight of nanoparticles, wherein the nanoparticles have an average particle size of 1000 nm or less per particle.
  • the nanoparticles can be dispersed as aggregate particles.
  • the nanoparticles are preferably dispersed as aggregate particles having an average particle size of 3000 nm or less.
  • Particles) section is used.
  • the manufacturing method of this expanded bead is not limited to the following manufacturing methods.
  • a method for producing a predetermined amount of polypropylene-based resin, polystyrene-based resin, and resin particles containing nanoparticles as described above a method using an extruder can be mentioned.
  • a predetermined amount of polypropylene-based resin, polystyrene-based resin, and a resin containing nanoparticles having an average particle size of 1000 nm or less per particle Particles can be prepared: (1) 100 parts by weight of polypropylene resin, 5 to 80 parts by weight of polystyrene resin, and 0.1 to 15 parts by weight of nanoparticles having an average particle size of 1000 nm or less per particle 0 parts by weight and, if necessary, appropriate amounts of other resins and the like and one or more selected from the group consisting of additives are blended to produce a blend; and melt-kneading the blend to prepare a polypropylene resin composition; (3) extruding the polypropylene resin composition from
  • melt-kneaded polypropylene resin composition is extruded directly into water from a die provided in an extruder, and the polypropylene resin composition is cut into particles immediately after extrusion, cooled, and solidified. Also good. By melt-kneading the blend in this manner, more uniform resin particles can be obtained.
  • the weight per particle of the resin particles obtained as described above is preferably 0.5 mg/particle to 3.0 mg/particle, more preferably 0.7 mg/particle to 2.5 mg/particle.
  • the handling property of the resin particles tends to be improved. tend to improve.
  • the foaming step comprises: (a) a dispersing step of dispersing resin particles, an aqueous dispersion medium, a foaming agent, and, if necessary, a dispersant and/or a dispersing aid in a vessel; (b) a temperature increase-increase step of increasing the temperature in the container to a constant temperature and increasing the pressure in the container to a constant pressure; (c) a holding step of holding the temperature and pressure in the container at a constant temperature and a constant pressure; (d) releasing one end of the container to release the dispersion in the container into a region (space) of lower pressure than the foaming pressure (ie, pressure inside the container).
  • the dispersing step can also be said to be, for example, a step of preparing a dispersion liquid in which resin particles, a foaming agent, and, if necessary, a dispersing agent and/or a dispersing aid are dispersed in an aqueous dispersion medium.
  • the container used in the dispersion step is not particularly limited, it is preferably a container that can withstand the foaming temperature and foaming pressure described below.
  • the container is preferably, for example, a pressure-resistant container, more preferably an autoclave-type pressure-resistant container.
  • the aqueous dispersion medium is not particularly limited as long as it can uniformly disperse the resin particles, foaming agent, and the like.
  • aqueous dispersion media include (a) dispersion media obtained by adding methanol, ethanol, ethylene glycol, glycerin, etc. to water, and (b) water such as tap water and industrial water.
  • water-based dispersion media include RO water (water purified by reverse osmosis membrane method), distilled water, deionized water (water purified by ion exchange resin), and the like. It is preferable to use pure water, ultrapure water, or the like.
  • the amount of the aqueous dispersion medium used is not particularly limited, but is preferably 100 to 400 parts by weight with respect to 100 parts by weight of the resin particles.
  • the amount of the aqueous dispersion medium used is (a) 100 parts by weight or more, there is no risk of deterioration in the stability of the dispersion (in other words, the resin particles are well dispersed), and (b) 400 parts by weight or less. In the case of , there is no possibility that the productivity of the expanded beads is lowered.
  • the foaming agent includes (a) (a-1) an inorganic gas such as nitrogen, carbon dioxide, air (a mixture of oxygen, nitrogen, and carbon dioxide), and (a-2) an inorganic foaming agent such as water; (b) (b-1) saturated hydrocarbons having 3 to 5 carbon atoms such as propane, normal butane, isobutane, normal pentane, isopentane and neopentane, (b-2) ethers such as dimethyl ether, diethyl ether and methyl ethyl ether , (b-3) halogenated hydrocarbons such as monochloromethane, dichloromethane, and dichlorodifluoroethane; and the like; As the foaming agent, at least one or more selected from the group consisting of the above inorganic foaming agents and organic foaming agents can be used.
  • the mixing ratio may be appropriately adjusted depending on the purpose.
  • the inorganic foaming agent is preferable as the foaming agent among those mentioned above.
  • carbon dioxide is preferable because it has a moderately high plasticizing effect and easily improves the expandability of the expanded beads in the production of the present expanded beads.
  • the amount of the foaming agent to be used is not particularly limited, and may be used appropriately according to (a) the type of foaming agent and/or (b) the desired expansion ratio of the foamed particles.
  • the amount of the foaming agent used is preferably 1 part by weight to 10000 parts by weight, more preferably 1 part by weight to 5000 parts by weight, and even more preferably 1 part by weight to 1000 parts by weight with respect to 100 parts by weight of the resin particles.
  • the amount of the foaming agent used is 1 part by weight or more with respect to 100 parts by weight of the resin particles, expanded beads having a suitable density can be obtained.
  • the amount of the foaming agent used is 10000 parts by weight or less with respect to 100 parts by weight of the resin particles, an effect corresponding to the amount of the foaming agent used can be obtained, and no economic waste occurs.
  • the amount of the foaming agent used may be, for example, 1 to 100 parts by weight or 1 to 10 parts by weight with respect to 100 parts by weight of the resin particles.
  • the water in the dispersion liquid in the container can be used as the foaming agent.
  • the resin particles contain a hydrophilic compound in advance. This makes it easier for the resin particles to absorb the water in the dispersion liquid in the container, and as a result, it becomes easier to use the water as a blowing agent.
  • a dispersant in the present method for producing expanded beads.
  • the use of a dispersant has the advantage of reducing coalescence (sometimes referred to as blocking) between resin particles and stably producing expanded beads.
  • examples of dispersants include inorganic substances such as tricalcium phosphate, trimagnesium phosphate, basic magnesium carbonate, calcium carbonate, barium sulfate, kaolin, talc, clay, aluminum oxide, titanium oxide, and aluminum hydroxide.
  • One type of these dispersants may be used alone, or two or more types may be mixed and used. When two or more dispersants are mixed and used, the mixing ratio may be appropriately adjusted depending on the purpose.
  • the amount of the dispersant used in the dispersion used in one embodiment of the present invention is preferably 0.01 to 3.00 parts by weight, preferably 0.05 to 2 parts by weight, relative to 100 parts by weight of the resin particles. 0.00 parts by weight is more preferred, and 0.10 to 1.00 parts by weight is even more preferred.
  • the amount of the dispersant used is (a) 0.01 parts by weight or more, there is no fear of causing poor dispersion of the resin particles, and (b) when it is 3.00 parts by weight or less, the obtained expanded beads are used. At the time of in-mold foam molding, there is no possibility of causing poor adhesion between foamed particles.
  • a dispersing aid is used to (a) improve the effect of reducing coalescence between resin particles and/or (b) improve the stability of the dispersion in the container.
  • Dispersing aids include, for example, anionic surfactants.
  • anionic surfactants include sodium alkylbenzenesulfonates such as sodium dodecylbenzenesulfonate, sodium alkanesulfonates, sodium alkylsulfonates, sodium alkyldiphenyletherdisulfonates, and sodium ⁇ -olefinsulfonates.
  • anionic surfactants include sodium alkylbenzenesulfonates such as sodium dodecylbenzenesulfonate, sodium alkanesulfonates, sodium alkylsulfonates, sodium alkyldiphenyletherdisulfonates, and sodium ⁇ -olefinsulfonates.
  • One type of these dispersing aids may be used alone, or two or more types may be
  • the amount of the dispersing aid used in the dispersion used in one embodiment of the present invention is preferably 0.001 to 0.500 parts by weight with respect to 100 parts by weight of the resin particles. It is more preferably from 0.200 parts by weight, and even more preferably from 0.010 parts by weight to 0.200 parts by weight. When the amount of the dispersing aid used is within the above range, there is no risk of poor dispersion of the resin particles.
  • part of the dispersant may adhere to the surface of the resulting expanded beads. They are not regarded as nanoparticles of any morphology.
  • the temperature raising-pressurization step is preferably performed after the dispersing step, and the holding step is preferably performed after the temperature raising-pressurization step.
  • the (a) constant temperature in the heating-pressurizing step and the holding step may be referred to as the foaming temperature
  • the (b) constant pressure may be referred to as the foaming pressure.
  • the foaming temperature cannot be defined unconditionally because it varies depending on the type of polypropylene resin, polystyrene resin and nanoparticles, the type of foaming agent, the desired apparent density of the foamed particles, and the like.
  • the foaming temperature is (i) (a) a mixture of polypropylene-based resin, polystyrene-based resin and nanoparticles, (b) polypropylene-based resin composition, or (c) melting point of resin particles -20.0°C to melting point +10.0 ° C., (ii) melting point of (a) polypropylene resin, polystyrene resin and nanoparticle mixture, (b) polypropylene resin composition, or (c) resin particles ⁇ 15.0° C.
  • melting point +8 melting point of (a) polypropylene-based resin, mixture of polystyrene-based resin and nanoparticles, (b) polypropylene-based resin composition, or (c) resin particles -10.0 °C to the melting point +6.0°C is more preferable.
  • the foaming pressure is preferably 1.0 MPa (gauge pressure) to 10.0 MPa (gauge pressure), more preferably 2.0 MPa (gauge pressure) to 5.0 MPa (gauge pressure), and 2.5 MPa (gauge pressure) to 3. 0.5 MPa (gauge pressure) is more preferred. If the foaming pressure is 1.0 MPa (gauge pressure) or more, expanded beads having a suitable density can be obtained.
  • the time (holding time) for holding the dispersion in the container near the foaming temperature and foaming pressure is not particularly limited.
  • the retention time is preferably 10 minutes to 60 minutes, more preferably 12 minutes to 55 minutes, even more preferably 15 minutes to 50 minutes.
  • the holding time is 10 minutes or more, there is a sufficient amount of unmelted crystals (polypropylene-based resin crystals), and as a result, shrinkage of the resulting expanded beads and/or an increase in open cell ratio can be reduced.
  • the holding time is 60 minutes or less, there is no excessive amount of unmelted crystals, so there is an advantage that the expanded beads can be molded at a low molding temperature.
  • the release step is preferably performed after (a) the temperature-increase-pressurization step when the holding step is not performed, or (b) after the holding step when the holding step is performed.
  • the expulsion step can cause the resin particles to expand, resulting in expanded particles.
  • area under pressure lower than the foaming pressure intends “area under pressure lower than the foaming pressure” or “space under pressure lower than the foaming pressure”, and “atmosphere at pressure lower than the foaming pressure”. It can also be called “lower”.
  • the region of pressure lower than the foaming pressure is not particularly limited as long as the pressure is lower than the foaming pressure, and may be, for example, a region under atmospheric pressure.
  • the dispersion In the ejection process, when the dispersion is ejected to a region with a pressure lower than the foaming pressure, the dispersion is passed through an orifice with a diameter of 1 mm to 5 mm for the purpose of adjusting the flow rate of the dispersion and reducing the variation in expansion ratio of the resulting expanded beads. can also be emitted.
  • the low-pressure region space may be filled with saturated steam.
  • method 1 in which a large amount of inorganic foaming agent is used in the first-stage expansion step. Furthermore, as a method other than method 1, after obtaining expanded beads (single-stage expanded beads) with a relatively low expansion ratio (expansion ratio of about 2.0 to 35.0 times) in the first-stage expansion process, A method of increasing the expansion ratio by expanding the stepped expanded particles again (hereinafter referred to as method 2) can also be employed.
  • Method 2 includes, for example, a method including the following (a1) to (a3) in order: (a1) using single-stage expanded particles having an expansion ratio of 2.0 to 35.0 times in the single-stage expansion step; (a2) Place the first-stage expanded particles in a pressure vessel and pressurize with nitrogen, air, carbon dioxide, etc. at 0.2 MPa (gauge pressure) to 0.6 MPa (gauge pressure) to produce one stage. (a3) A method in which the pressure inside the expanded bead (hereinafter sometimes referred to as “internal pressure”) is raised above normal pressure; (a3) After that, the first-stage expanded bead with increased internal pressure is heated with steam or the like to further expand.
  • the step of increasing the expansion ratio of the single-stage expanded beads as in Method 2 is called the "second-stage expansion process", and the polypropylene-based expanded beads obtained by Method 2 are called “two-stage expanded beads”.
  • the pressure of steam for heating the first-stage expanded beads is 0.03 MPa (gauge pressure) to 0.20 MPa ( gauge pressure).
  • the steam pressure in the two-stage expansion step is 0.03 MPa (gauge pressure) or more, the expansion ratio tends to be improved, and when it is 0.20 MPa (gauge pressure) or less, the obtained two-stage expanded particles are separated from each other. are less likely to coalesce.
  • the obtained two-stage expanded beads may not be able to be subjected to subsequent in-mold foam molding.
  • the internal pressure of the first-stage expanded particles obtained by impregnating the first-stage expanded particles with nitrogen, air, carbon dioxide, or the like can be appropriately changed in consideration of the expansion ratio of the second-stage expanded particles and the water vapor pressure in the second-stage expansion process. desirable.
  • the internal pressure of the first-stage expanded beads is preferably 0.15 MPa (absolute pressure) to 0.60 MPa (absolute pressure), more preferably 0.20 MPa (absolute pressure) to 0.60 MPa (absolute pressure), and 0.30 MPa (absolute pressure). pressure) to 0.60 MPa (absolute pressure) is more preferable.
  • polypropylene foam molded product In one embodiment of the present invention, there is provided a foam molded article formed by molding the foamed particles.
  • the polypropylene-based foamed molded article according to one embodiment of the present invention is the same as described in [2. Polypropylene-Based Expanded Particles].
  • polypropylene-based foam molded article according to one embodiment of the present invention
  • this foam molded article may be referred to as “this foam molded article”.
  • the present foamed molded product has the advantage that it has almost no shrinkage or deformation after molding because it has the above-described structure.
  • the foam molded article preferably has a shrinkage rate of 1.0% or less, more preferably 0.9% or less, even more preferably 0.8% or less, and 0.7% or less. It is particularly preferred to have A foamed molded article having a shrinkage rate of 1.0% or less is a foamed molded article with reduced shrinkage (almost no shrinkage) that is less prone to dimensional variations due to shrinkage of the foamed molded article. It can be said that it is a molded body.
  • the foamed particles that can provide a foamed molded article whose shrinkage is suppressed and the foamed molded article have the advantage that they can be suitably used in the field of insert molding in which they are integrally molded with other materials such as metals.
  • FIG. 1 is a schematic diagram of a foam molded article 100 used for evaluation of the amount of deformation.
  • the foam molded article 100 is manufactured using a mold (longitudinal direction 350 mm ⁇ lateral direction 320 mm ⁇ thickness direction (driving direction of moving mold) 180 mm) having a partition plate in the center of the mold.
  • the X direction can be said to be the thickness direction of the foam molded body 100, and can also be said to be the driving direction of the moving mold.
  • the Y direction can also be said to be the longitudinal direction of the foam molded article 100, and is a direction perpendicular to the X direction.
  • the Z direction can also be said to be the lateral direction of the foam molded article 100, and is a direction perpendicular to each of the X direction and the Y direction.
  • the Z-direction dimensions (lengths) of the two ends in the longitudinal direction are K1 and K2, respectively, and the Z-direction dimension of the central part in the longitudinal direction is K3.
  • the phrase "almost no deformation" with respect to the foamed molded product means that the amount of deformation measured by the following methods (1) to (3) is small: (1) longitudinal direction ( Using a mold having a dimension (length) of 350 mm in the Y direction), 320 mm in the lateral direction (Z direction) and 180 mm in the thickness direction (X direction), and having a partition plate in the center of the mold, foamed particles are produced.
  • the deformation amount of the foam molded article is preferably 10.0 mm or less, more preferably 9.0 mm or less, further preferably 8.0 mm or less, and more preferably 7.0 mm or less. More preferably, it is particularly preferably 6.0 mm or less.
  • a foam-molded article having a deformation amount of 10.0 mm or less can be said to be a foam-molded article with suppressed deformation (almost no deformation) in which dimensional variations are unlikely to occur in the produced foam-molded article.
  • the method for producing the present foam molded article is not particularly limited, and known methods can be applied.
  • a method for producing the present foam molded article for example, the above [2.
  • Expanded polypropylene beads according to one embodiment of the present invention described in the section of "Expanded polypropylene beads” or expanded polypropylene beads obtained by the manufacturing method described in the section ⁇ Method for manufacturing expanded polypropylene beads> A manufacturing method having a molding step (molding step) is mentioned.
  • a specific embodiment of the present foam molded product manufacturing method includes, for example, a manufacturing method (in-mold foam molding method) including the following (b1) to (b6) in order, but is limited to such a manufacturing method. not what: (b1) A mold composed of a fixed mold that cannot be driven and a movable mold that can be driven is mounted on an in-mold foam molding machine.
  • the fixed mold and the movable mold can be formed inside the fixed mold and the movable mold by driving the movable mold toward the fixed mold (this operation is sometimes referred to as "mold closing"); (b2) driving the movable mold toward the fixed mold so that a slight gap (also called cracking) is formed so that the fixed mold and the movable mold are not completely closed; (b3) filling the foamed particles into the molding space formed inside the stationary mold and the moving mold, for example through a filling machine; (b4) driving the movable mold so that the fixed mold and the movable mold are completely closed (that is, the mold is completely closed); (b5) performing in-mold foam molding by preheating the mold with steam, heating the mold in one direction and in reverse with steam, and heating both sides of the mold with steam; (b6) Cooling the mold with water to such an extent that deformation of the in-mold foam-molded product after removal can be suppressed, then removing the in-mold foam-molded product from the mold and drying (for example,
  • a method of filling the molding space with the foamed particles after application (b3-2) A method of filling the molding space with foamed particles and then compressing them so as to reduce the volume in the mold by 10% to 75%; (b3-3) A method of compressing foamed particles with gas pressure to fill the molding space; (b3-4) A method of filling a molding space with expanded particles without any particular pretreatment.
  • At least one selected from the group consisting of air, nitrogen, oxygen, carbon dioxide, helium, neon, argon, etc. can be used as the inorganic gas in the method (b3-1) of the present method for producing a foamed molded product.
  • air and/or carbon dioxide are preferred.
  • the internal pressure of the foamed particles in the method (b3-1) of the method for producing the present foamed molded product is preferably 0.10 MPa (absolute pressure) to 0.30 MPa (absolute pressure), and more preferably 0.11 MPa (absolute pressure) to 0.1 MPa (absolute pressure). 25 MPa (absolute pressure) is preferred.
  • the temperature in the container when impregnating the foamed particles with the inorganic gas in the method (b3-1) of the method for producing the foamed molded article is preferably 10°C to 90°C, more preferably 40°C to 90°C. .
  • the restoring force of the foamed particles compressed by gas pressure is used to fuse the foamed particles.
  • the in-mold foam-molded product immediately after in-mold foam molding is at a high temperature and is in a state of being very easily deformed.
  • the in-mold foam-molded product is significantly deformed, making it difficult to obtain a foam-molded product having a desired shape. Therefore, before removing the in-mold foam-molded product from the mold, the mold is cooled, and the resin pressure of the in-mold foam-molded product in the mold is reduced to a pressure that can suppress deformation (for example, 0. 01 MPa (gauge pressure)).
  • the method for producing a polypropylene-based foam-molded article according to an embodiment of the present invention preferably includes a step (cooling step) of cooling the polypropylene-based foam-molded article (immediately after molding).
  • the method of cooling the polypropylene-based foamed molded article is not particularly limited, and for example, a method of water cooling using water at 30°C can be mentioned.
  • the time (cooling time) required for cooling the mold is affected by the type (composition) of the foamed particles that are the raw material of the foamed molded article in the mold.
  • the productivity of foamed moldings is evaluated by this cooling time. It can be said that the shorter the cooling time is, the more excellent the productivity of the foamed molded product is, and it can be said that the foamed particles can provide the foamed molded product of excellent productivity.
  • the cooling time of the foamed molded article can be measured, for example, by the following method: (1) The foamed molded article is (2) Water-cool the obtained foamed molded article using water at 30 ° C. until the resin pressure reaches 0.01 MPa; (3) The time required for this water cooling is Time.
  • the cooling time of the present foam molded article is preferably 100.0 seconds or less, more preferably 90.0 seconds or less, and 80.0 seconds or less, from the viewpoint of further improving productivity. is more preferably 70.0 seconds or less, and particularly preferably 60.0 seconds or less. It can be said that the shorter the cooling time, the more excellent the productivity of the foam molded product.
  • the present foamed beads are foamed beads capable of providing a foamed molded article having a cooling time of 100.0 seconds or less. Therefore, it can be said that the foamed beads are foamed beads whose cooling time is 100.0 seconds or less.
  • An embodiment of the present invention may include the following configuration.
  • [1] Contains 100 parts by weight of polypropylene resin, 5 parts by weight to 80 parts by weight of polystyrene resin, and 0.1 parts by weight to 15.0 parts by weight of nanoparticles, and the nanoparticles are Expanded polypropylene particles having an average particle size of 1000 nm or less and dispersed as aggregate particles having an average particle size of 3000 nm or less.
  • polystyrene resin is one or more selected from the group consisting of polystyrene homopolymers and copolymers containing acrylonitrile units and styrene units.
  • the polystyrene resin is one or more selected from the group consisting of polystyrene homopolymers, acrylonitrile/styrene copolymers, and acrylonitrile/ ⁇ -methylstyrene copolymers [1] to [8] ]
  • the expanded polypropylene particles according to any one of .
  • a step of expanding polypropylene-based resin particles to form expanded particles The polypropylene resin particles contain 100 parts by weight of polypropylene resin, 5 parts by weight to 80 parts by weight of polystyrene resin, and 0.1 parts by weight to 30.0 parts by weight of nanoparticles.
  • polystyrene resin is one or more selected from the group consisting of polystyrene homopolymers and copolymers containing acrylonitrile units and styrene units.
  • the polystyrene resin is one or more selected from the group consisting of polystyrene homopolymers, acrylonitrile/styrene copolymers, and acrylonitrile/ ⁇ -methylstyrene copolymers [21] to [26] ] and the method for producing expanded polypropylene particles according to any one of
  • the polypropylene-based resin particles do not contain a styrene-based thermoplastic elastomer, or contain a styrene-based thermoplastic elastomer in an amount of more than 0 parts by weight and 10 parts by weight or less with respect to 100 parts by weight of the polypropylene-based resin.
  • the melting point of the polypropylene-based resin was a value obtained by measurement by the DSC method using a differential scanning calorimeter (manufactured by Seiko Instruments Inc., model DSC6200).
  • the specific operating procedures were as follows (1) to (4): (1) The temperature of 5 mg to 6 mg of polypropylene resin was increased from 40.0° C. to 220° C. at a rate of 10.0° C./min. (2) Thereafter, the temperature of the melted polypropylene resin was lowered from 220.0°C to 40.0°C at a rate of 10.0°C/min.
  • the temperature of the crystallized polypropylene resin was increased from 40.0°C to 220°C at a rate of 10.0°C/min.
  • the temperature of the peak (melting peak) of the DSC curve of the polypropylene resin obtained when the temperature was raised for the second time (that is, at the time of (3)) was taken as the melting point of the polypropylene resin.
  • the temperature of the peak (melting peak) with the maximum amount of heat of fusion is The melting point of the polypropylene resin was used.
  • Glass transition temperature (Tg) of polystyrene resin The glass transition temperature (Tg) of the polystyrene resin is measured using a differential scanning calorimeter [manufactured by Seiko Instruments Inc., model DSC6200], in accordance with JIS-K-7121, using the following (1) to (5).
  • the MI of the polypropylene-based resin or polystyrene-based resin was a value obtained by measuring under the following conditions using an MI measuring instrument described in JIS K7210: 1999: the diameter of the orifice was 2.0959 ⁇ 0.005 mm ⁇ . , an orifice length of 8.000 ⁇ 0.025 mm, a load of 2.16 kgf, and a temperature of 230° C. (230 ⁇ 0.2° C.).
  • the average particle size of the nanoparticles (aggregate particles) in the expanded beads was measured by the following (1) to (4): (1) The expanded beads were measured using an ultramicrotome (UC6 manufactured by Leica).
  • the major diameter (maximum Feret diameter) of the aggregate-like particles is intended to be the maximum distance between two parallel lines drawn along the outer edge of the aggregate-like particles.
  • the short diameter (minimum Feret diameter) of the aggregate-like particles means the minimum distance between two parallel lines drawn along the outer edge of the aggregate-like particles.
  • the average particle size of the nanoparticles (primary particles) in the expanded beads was measured by the following methods (1) to (4): (1) The expanded beads were measured using an ultramicrotome (UC6 manufactured by Leica). (2) A transmission electron microscope (TEM, H-7650 manufactured by Hitachi High-Technologies Corporation) was used for the obtained ultra-thin section. , a photograph (image) magnified 40,000 times was obtained; (3) In the obtained TEM photograph, among the primary particles of the nanoparticles constituting the aggregate-like particles, arbitrary primary particles of the nanoparticles were selected.
  • TEM transmission electron microscope
  • the major diameter (maximum Feret diameter) and the minor diameter (minimum Feret diameter) of the primary particles of the nanoparticles were measured, and the average value was calculated as the particle diameter of the primary particles of the nanoparticles; (4) 50 in total
  • the particle size of the primary particles of the nanoparticles is calculated by the method of (3) above, and the average value of the particle sizes of the primary particles of 50 nanoparticles is was the average particle size of the nanoparticles (primary particles).
  • the major diameter (maximum Feret diameter) of the primary particle of the nanoparticle means the maximum distance between two parallel lines drawn along the outer edge of the primary particle of the nanoparticle.
  • the short diameter (minimum Feret diameter) of the primary particle of the nanoparticle is the minimum distance between the parallel lines when two parallel lines are drawn along the outer edge of the primary particle of the nanoparticle. do.
  • DSC ratio of expanded particles (first-stage expanded particles) A differential scanning calorimeter (DSC6200 manufactured by Seiko Instruments Inc.) was used to measure (calculate) the DSC ratio of the expanded beads (first-stage expanded beads).
  • the method of measuring (calculating) the DSC ratio of the expanded beads using a differential scanning calorimeter was as follows (1) to (5): (1) 5 mg to 6 mg of expanded beads were weighed; (2) The temperature of the expanded beads was increased from 40° C. to 220° C.
  • the open cell ratio of the expanded beads is measured using an air-comparative hydrometer [manufactured by Tokyo Science Co., Ltd., Model 1000] according to the method described in ASTM D2856-87 Procedure C (PROSEDURE C). , measured and determined.
  • the mold used for measuring the shrinkage rate may be referred to as a shrinkage evaluation mold.
  • the deformation amount of the foam molded body was measured by the following (1) to (3): (1) 350 mm in the longitudinal direction (Y direction), 320 mm in the transverse direction (Z direction) and 320 mm in the thickness direction (X direction).
  • the foamed particles were foam-molded in the mold;
  • the mold used for measuring the amount of deformation may be referred to as a mold for evaluating the amount of deformation.
  • Example 1 (Production of polypropylene resin particles) 100 parts by weight (10 kg) of polypropylene resin, 30 parts by weight (3.0 kg) of styrene resin A, 3 parts by weight (0.3 kg) of nanoparticles A, and 0.25 parts by weight of glycerin as a hydrophilic compound (25 g) and 0.050 parts by weight (5 g) of talc as a crystal nucleating agent were dry-blended.
  • “parts by weight” may be referred to as "parts”.
  • the resulting blend was put into a twin-screw extruder [TEM26-SX, manufactured by Toshiba Machine Co., Ltd.] and melt-kneaded at a resin temperature of 250°C.
  • the melt-kneaded polypropylene-based resin composition was extruded into strands through a die having a circular hole attached to the tip of the extruder.
  • the extruded polypropylene-based resin composition was cooled with water and then cut with a cutter to obtain cylindrical resin particles (1.2 mg/particle).
  • the water cooling time was 56.0 seconds. After cooling with water, the foamed molded article was cured and dried in a constant temperature room at 75° C. for 12 hours, and then left at room temperature for 4 hours. After that, the contraction rate and the amount of deformation of the obtained foam molded article were evaluated by the methods described above. Table 1 shows the results.
  • Examples 1 to 11, Comparative Examples 1 to 9 Expanded beads and an expanded molded product were obtained in the same manner as in Example 1, except that the kind and amount of each material and the production conditions were changed as shown in Tables 1 and 2. Each physical property was measured and evaluated for the obtained expanded beads and expanded molded article. Results are shown in Tables 1 and 2.
  • the expanded beads obtained in Comparative Example 4 had an excessively high open cell ratio, so they could not be expanded in two stages, and they shrunk excessively during molding, making it impossible to obtain a foamed molded article. rice field.
  • the polypropylene-based foamed particles according to one embodiment of the present invention can provide a polypropylene-based foamed molded article with suppressed shrinkage and deformation after molding with good productivity.
  • Polypropylene-based foamed molded articles can be suitably used in various applications such as cushioning packaging materials, distribution materials, heat insulating materials, civil engineering and construction members, and automobile members.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)

Abstract

La présente invention aborde le problème de la fourniture de particules expansées à base de polypropylène à partir desquelles une mousse moulée à base de polypropylène qui a rétréci ou s'est déformée peu après le moulage peut être obtenue avec une efficacité de production élevée. Les particules expansées à base de polypropylène comprennent des quantités données d'une résine à base de polypropylène, d'une résine à base de polystyrène et de nanoparticules dispersées sous la forme de particules agrégées ayant un diamètre de particule moyen inférieur ou égal à 3 000 nm.
PCT/JP2022/047808 2022-01-07 2022-12-26 Particules expansées à base de polypropylène et mousse moulée à base de polypropylène WO2023132281A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2023572442A JPWO2023132281A1 (fr) 2022-01-07 2022-12-26

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2022001810 2022-01-07
JP2022-001810 2022-01-07

Publications (1)

Publication Number Publication Date
WO2023132281A1 true WO2023132281A1 (fr) 2023-07-13

Family

ID=87073595

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/047808 WO2023132281A1 (fr) 2022-01-07 2022-12-26 Particules expansées à base de polypropylène et mousse moulée à base de polypropylène

Country Status (2)

Country Link
JP (1) JPWO2023132281A1 (fr)
WO (1) WO2023132281A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001179795A (ja) * 1999-12-28 2001-07-03 Kanegafuchi Chem Ind Co Ltd ポリプロピレン系樹脂押出板状発泡体
JP2001187824A (ja) * 1999-12-28 2001-07-10 Kanegafuchi Chem Ind Co Ltd ポリプロピレン系樹脂およびポリスチレン系樹脂の混合樹脂押出発泡ボード
JP2008075076A (ja) * 2006-08-25 2008-04-03 Sekisui Plastics Co Ltd スチレン改質ポリプロピレン系樹脂粒子及びその発泡性樹脂粒子、それらの製造方法、予備発泡粒子及び発泡成形体
JP2011208066A (ja) * 2010-03-30 2011-10-20 Sekisui Plastics Co Ltd 発泡成形体、車両用内装材、車両用タイヤスペーサおよび車両用ラゲージボックス
JP2012214552A (ja) * 2011-03-31 2012-11-08 Sekisui Plastics Co Ltd シード重合用ポリプロピレン系樹脂粒子、その製造方法、複合樹脂粒子、発泡性複合樹脂粒子、予備発泡粒子および発泡成形体
WO2015182721A1 (fr) * 2014-05-30 2015-12-03 積水テクノ成型株式会社 Article moulé en mousse et procédé pour fabriquer celui-ci

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001179795A (ja) * 1999-12-28 2001-07-03 Kanegafuchi Chem Ind Co Ltd ポリプロピレン系樹脂押出板状発泡体
JP2001187824A (ja) * 1999-12-28 2001-07-10 Kanegafuchi Chem Ind Co Ltd ポリプロピレン系樹脂およびポリスチレン系樹脂の混合樹脂押出発泡ボード
JP2008075076A (ja) * 2006-08-25 2008-04-03 Sekisui Plastics Co Ltd スチレン改質ポリプロピレン系樹脂粒子及びその発泡性樹脂粒子、それらの製造方法、予備発泡粒子及び発泡成形体
JP2011208066A (ja) * 2010-03-30 2011-10-20 Sekisui Plastics Co Ltd 発泡成形体、車両用内装材、車両用タイヤスペーサおよび車両用ラゲージボックス
JP2012214552A (ja) * 2011-03-31 2012-11-08 Sekisui Plastics Co Ltd シード重合用ポリプロピレン系樹脂粒子、その製造方法、複合樹脂粒子、発泡性複合樹脂粒子、予備発泡粒子および発泡成形体
WO2015182721A1 (fr) * 2014-05-30 2015-12-03 積水テクノ成型株式会社 Article moulé en mousse et procédé pour fabriquer celui-ci

Also Published As

Publication number Publication date
JPWO2023132281A1 (fr) 2023-07-13

Similar Documents

Publication Publication Date Title
JP6421165B2 (ja) ポリプロピレン系樹脂発泡粒子およびポリプロピレン系樹脂発泡粒子の製造方法
JP5107692B2 (ja) ポリプロピレン系樹脂発泡粒子、及びその発泡粒子成形体
WO2016060162A1 (fr) Particules expansées de résine de polypropylène, corps moulé par moussage dans le moule de résine de polypropylène, et leur procédé de fabrication
WO2017169260A1 (fr) Particules expansibles de résine de polypropylène, corps moulé en mousse dans le moule de résine de polypropylène, et son procédé de production
JP5587605B2 (ja) ポリプロピレン系樹脂予備発泡粒子および該予備発泡粒子から得られる型内発泡成形体
JP6637903B2 (ja) ポリプロピレン系樹脂発泡粒子
WO2022149538A1 (fr) Particules de mousse de résine de polypropylène et article moulé en mousse de résine de polypropylène
WO2016147919A1 (fr) Particules moussées en résine de polypropylène et leur procédé de production
JP2010248341A (ja) ポリプロピレン系樹脂予備発泡粒子
WO2023132281A1 (fr) Particules expansées à base de polypropylène et mousse moulée à base de polypropylène
WO2019220994A1 (fr) Particules expansées en résine de polypropylène, corps en résine de polypropylène moulé par expansion, et procédé de production de particules expansées en résine de polypropylène
JP5358452B2 (ja) ポリプロピレン系樹脂発泡粒子および発泡成形体
JP5080842B2 (ja) ポリプロピレン系樹脂予備発泡粒子および型内発泡成形体
JP6038479B2 (ja) ポリプロピレン系樹脂型内発泡成形体
WO2022186313A1 (fr) Particules de mousse de résine de polypropylène et article moulé en mousse de résine de polypropylène
JP6625472B2 (ja) ポリプロピレン系樹脂発泡粒子、および、ポリプロピレン系樹脂型内発泡成形体、およびその製造方法
JP5749039B2 (ja) ポリプロピレン系樹脂発泡粒子、ポリプロピレン系樹脂型内発泡成形体、およびポリプロピレン系樹脂発泡粒子の製造方法
JP4863542B2 (ja) ポリオレフィン系樹脂予備発泡粒子の製造方法
WO2023176805A1 (fr) Particules de mousse à base de polypropylène et procédé de production de particules de mousse à base de polypropylène
JP2007302720A (ja) ポリプロピレン系樹脂予備発泡粒子およびその型内発泡成形体
JP2024123758A (ja) ポリプロピレン系樹脂粒子の製造方法、ポリプロピレン系発泡粒子の製造方法およびポリプロピレン系発泡成形体の製造方法
WO2024204495A1 (fr) Procédé de production d'un corps moulé en mousse de résine de polypropylène
JP5248939B2 (ja) ポリプロピレン系樹脂発泡粒子
WO2024204000A1 (fr) Particules expansées à base de polypropylène, article expansé à base de polypropylène et leurs procédés de production
JP7269220B2 (ja) ポリプロピレン系樹脂発泡粒子およびその製造方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22918865

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2023572442

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE