| 摘要 |
PURPOSE:The titled particles which can be formed in good moldability into an in-mold molding of excellent flexibility and elongation, prepared by pre-expanding a resin obtained by crosslinking a linear super-low-density polyethylene to a specified gel content. CONSTITUTION:A linear super-low-density polyethylene (of a density of 0.88- 0.914g/cm<3> and a melt flow rate of 0.01-10g/10min) is crosslinked in the presence of a chemical crosslinking agent by heating, electron beam irradiation or like means, so that the gel content of the particles may be 0.06-45% when pre- expanded. 100pts.wt. of said crosslinked resin particles are dispersed in about 10-30pts.wt. blowing agent in a pressure vessel, and heated at a temperature of from (the m.p. of the resin minus 2 deg.C) to (the m.p. of the resin plus 30 deg.C) under an elevated pressure and then released to atmospheric pressure to obtain pre-expanded particles (cell diameter of about 10-2,000mu). |
