Direct condition for foaming low the density polyethylene resin coloration grain and direct condition it is low density polyethylene resin preexpansion coloration grain

摘要

PURPOSE:To obtain colored expansible linear low density polyethylene resin particles improved in secondary expansibility during expansion molding by adding an organic pigment and a specified nonionic surfactant in a specified weight ratio to a linear low density polyethylene. CONSTITUTION:100 pts.wt. linear low density polyethylene resin (A) of a density of 0.915-0.935g/cm3 and an MI of 0.1-5.0 is mixed with 0.05-5 pts.wt. nonionic surfactant (B) (e.g. sorbitan fatty acid ester) and an organic pigment (C) in such amounts that the weight ratio of component C to component B is (1:10)-(1:50), and melt-kneaded at 100-200 deg.C, and the melt is extruded into a strand, which is pelletized to obtain colored expansible linear low density polyethylene resin particles. 100 pts.wt. these particles are impregnated with 3-40 pts.wt. blowing agent (e.g. propane), kept under high temperature and high pressure conditions, and expanded by releasing them into a lower pressure atmosphere to obtain colored preexpanded linear low density polyethylene resin particles.