| 摘要 |
PROBLEM TO BE SOLVED: To provide a thick polyethylene resin mixture foam which can be produced with good foamability, has good stiffness and adhesiveness, and contains closed cells in a large proportion, by subjecting to extrusion foaming a polyethylene resin mixture containing, as a main component, a mixed resin of a low density polyethylene and a polystyrene resin, under conditions such that the resin mixture foam has a specific closed cell ratio and a specific density. SOLUTION: A low density polyethylene usable is an ethylene polymer having a density of 0.910 to 0.930g/cm<3> , and includes a copolymer with a vinyl monomer copolymerizable with ethylene. The polyethylene has a melt index of 0.05 to 10g/10min. A polystyrene resin usable is a polymer composed mainly of styrene and includes a styrene homopolymer, a copolymer with a monomer copolymerizable with styrene and a high impact polystyrene. The polystyrene resin has a melt flow rate of 6 to 40g/10min and a weight average molecular weight of 100,000 to 330,000. A resin mixture of these resins is subjected to extrusion foaming so as to produce a foam having a closed cell ratio of 30 to 85% and a density of 0.04 to 0.001g/cm<3> . |
