Expandable thermoplastic resin beads and and expanded molded articles made from them

摘要

An object of the invention is to prevent an oil from penetrating into a vessel obtained from expandable thermoplastic resin beads through molding.The above object is achieved by expandable thermoplastic resin beads whose surface or surface layer is coated or incorporated with a fluorine-containing block copolymer comprising of a fluorine-containing vinyl-type polymer segment derived from a fluorine-containing vinyl-type monomer and a lipophilic vinyl-type polymer segment derived from a lipophilic vinyl-type monomer.