| 摘要 |
PURPOSE:To produce the titled foam excellent in heat resistance and heat stability and high in open-cell rate, by expanding a composition comprising crosslinkable high-pressure process branched polyethylene and a linear medium-low density polyethylene having a m.p. in a specified temperature range in the presence of a catalyst and bringing the molding into contact with water. CONSTITUTION:Crosslinkable high-pressure process branched polyethylene is obtained by grafting an unsaturated silane having a hydrolyzable organic group onto high-pressure process branched polyethylene having a density of about 0.915-0.935g/cm<3>, a MI of about 0.1-20, and a m.p. >=about 108 deg.C. 95-50wt% said polyethylene is mixed with 5-50wt% linear medium-low density polyethylene having a m.p. in the temperature range represented by the relationship. 100pts.wt. obtained composition is molten by heating. To this melt, a silanol condensation catalyst (e.g., dibutyltin dilaurate) and 5-50pts.wt. volatile blowing agent (e.g., dichlorodifluoromethane) are added, and the resulting mixture is extruded into a low-pressure zone and brought into contact with water. |
