摘要 |
<P>PROBLEM TO BE SOLVED: To provide ultra high molecular weight polyethylene particles exhibiting a high bulk density, a good flowability and the small entanglement of polymer chains in a molding method such as a solid state-stretching method, by using the polymer particles. <P>SOLUTION: The ultrahigh molecular weight polyethylene particles are characterized by having (1)≥10 and ≤20 dL/g intrinsic viscosity [η], (2)≥0.35 and ≤0.48 g/cm<SP POS="POST">3</SP>bulk density and (3)≥20 and ≤60 sec for falling 50 g particles through a funnel, satisfying (4) numerical equation 1 (1.15≤ΔH1/ΔH2≤1.35) by the relationship regarding the amount of heat of fusion at first time (ΔH1) to the amount of heat of fusion at second time (ΔH2) measured by a differential scanning calorimeter, and having (5)≥40 and ≤200 ppm sum of the contents of magnesium, titanium and aluminum contained in the polymer particles. <P>COPYRIGHT: (C)2012,JPO&INPIT |