| 摘要 |
PROBLEM TO BE SOLVED: To obtain a foamed sheet comprising a modified polypropylene-based resin composition, having excellent secondary moldability, capable of providing a molding product excellent in heat resistance and heat insulating properties. SOLUTION: This foamed sheet comprises a modified polypropylene-based resin composition obtained by melting and kneading a polypropylene-based resin, an isoprene monomer and a radical polymerization initiator. The polypropylene-based resin, the isoprene monomer and the radical polymerization initiator are melted and kneaded to give a resin composition, which is blended with a blowing agent at a high temperature under high pressure, extruded through an annular die in a low pressure and foamed into a cylindrical shape. The cylindrical foam is drawn/cooled by a cooling column equipped with a diameter enlarging part at the die side, cut and opened and taken-off in a sheetlike shape to give the objective foamed sheet. |
