Method for producing a polypropylene-based resin foam particles, polypropylene resin mold molded foam and expanded polypropylene resin beads

摘要

PROBLEM TO BE SOLVED: To provide polypropylene resin expanded particles which do not show excessive expansion, even when heated at a temperature enabling mutual fusing of the expanded particles, their preparation process and an in-mold expansion molded product of a polypropylene resin obtained from the expanded particles.;SOLUTION: The preparation process comprises a surface-reforming step wherein substantially non-crosslinked, surface-reformed particles are obtained by dispersing polypropylene resin particles having through-holes in a dispersion medium containing an organic peroxide to prepare a dispersion medium and heating the medium to a temperature which is lower than a melting point of a base resin of the resin particles but substantially decomposes the organic peroxide to decompose the organic peroxide, and an expansion step wherein the substantially non-crosslinked expanded particles having the through-holes are obtained by expanding the surface-reformed particles.;COPYRIGHT: (C)2004,JPO