Patent ID: 6489426
Filing Date: 2002-12-03
Classification: C08F,C08J

Abstract:
A propylene base polymer having the following characteristics (1) to (5):(1) it is a propylene homopolymer or a propylene-olefin copolymer with at least one olefin selected from &agr;-olefins having 4 or more carbon atoms, wherein a propylene content in this copolymer is 98% by weight or more, (2) a melt flow rate (MFR: 230Â° C., 21.18N) falls in a range of 0.5 to 20 dg/min, (3) an isotactic pentad fraction (mmmm) falls in a range of 0.89 to 0.95, (4) boiling pentane extractables (C5-Ext) are 0.5% by weight or more; boiling heptane extractables (C7-Ext) are 5% by weight or less; and (C5-Ext) and (C7-Ext) reside in a relation of (C7-Ext)<3.5 (C5-Ext), and (5) solubles of 0Â° C. or lower obtained by a cross fractionation chromatography have a weight average molecular weight of 7Ã—104 g/mol or more, and solubles of 50Â° C. or lower have a weight average molecular weight of 6Ã—104 g/mol or more.