Expandable modified resin beads, expanded modified resin beads, and foamed molded article formed from expanded modified resin beads

摘要

Disclosed is expandable modified resin beads (1), comprising a modified resin as a base resin in which a dispersion phase (3) containing a styrene resin as a major component is dispersed in a continuous phase (2) containing an olefin resin as a major component, and a physical blowing agent. Further disclosed are expanded modified resin beads obtained by expanding the expandable modified resin beads (1), and a foamed molded article formed from the expanded modified resin beads obtained by molding the expanded modified resin beads in a mold. A volume average diameter of the dispersion phase (3) dispersed in the continuous phase (2) is 0.55 μm or more. The expandable modified resin beads (1) have, as a base resin, the modified resin contains 80 to 50 parts by mass of the styrene resin with respect to 20 to 50 parts by mass parts of the olefin resins.

主权项

1. A method for producing an expandable modified resin bead, comprising a modified resin as a base resin and a physical blowing agent, wherein the modified resin comprises a continuous phase comprising an olefin resin and a dispersion phase, dispersed in the continuous phase, comprising a styrene resin,
the method comprising: impregnating styrene-based monomers into a nuclear particle comprising the olefin resin and a dispersion diameter-enlarging agent capable of enlarging a volume average diameter of the dispersion phase; polymerizing the styrene-based monomers to obtain a modified resin bead having a continuous phase and a dispersion phase; and impregnating the resin bead with a physical blowing agent during or after polymerization of the styrene-based monomers, wherein the dispersion diameter enlarging agent comprises at least one substance selected from the group consisting of a methyl methacrylate-styrene copolymer, polystyrene, a styrene-based elastomer selected from a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, and a hydrate of these block copolymers, rubber modified polystyrene, an ABS resin, an AES resin, polyvinyl chloride, and polyvinylidene chloride, in which the substance is different from the styrene resin of the dispersion phase.