Prime Polymer Co., Ltd.

Yoshio Yanagishita

Satoshi Tamura

Katsutoshi Ohta

Chikara Satou

[Problem] To provide polypropylene for a microporous film having excellent heat resistance and strength. [Solution] Polypropylene for a microporous film satisfying the following requirements (1) and (2): (1) the weight-average molecular weight (Mw) value, as determined by gel permeation chromatography (GPC), is not less than 100,000 but less than 800,000, the value (Mw/Mn) obtained by dividing the weight-average molecular weight by the number-average molecular weight is more than 7.0 but not more than 12.0, and the value (Mz/Mw) obtained by dividing the Z-average molecular weight by the weight-average molecular weight is not less than 3.8 but not more than 9.0, and (2) the mesopentad fraction, as measured byC-NMR (nuclear magnetic resonance method), is not less than 95.5%.

Growing community of inventors

Ichihara, Japan

Yoshio Yanagishita