| 摘要 |
PURPOSE:To obtain directly and easily, uniform prefoamed particles of a high expansion ratio from polyolefin resin particles without using pelletized polymer particles or particles prepd. by grinding pellets by means of a grinder, by using polyolefin resin particles having specified particle diameter and particle size distribution. CONSTITUTION:The title prefoamed particles are obtained from polyolefin resin particles which are obtd. by polymerizing an olefin with a Ziegler-Natta catalyst and wherein the content of particles having a particle diameter of 105mu or less is 1wt.% or less and a particle size distribution is represented by De>=300 and n>=2.5 in equation I. In this equation, Dp is the particle diameter (mu) of the polymer particles; R(Dp) is a cumulative oversize distribution (by wt.%); De is a particle size characteristic number and equals the particle diameter (mu) corresponding to R(Dp) of 36.8wt.%; n is a distribution constant. |
