Patent ID: 6403708
Filing Date: 2002-06-11
Classification: C08F

Abstract:
Crystalline propylene block copolymer comprising components insoluble in 64Â° C. decane, said components having the following characteristics:(1) limiting viscosity (&eegr;) (in 135Â° C. decalin) of from 0.5 to 10 dl/g; (2) molecular weight distribution (Mz/Mw), determined by gel permeation chromatography (GPC; solvent: o-dichlorobenzene, measurement temperature: 140Â° C.) of at least 5; (3) pentad isotacticity (mmmm percentage), which is a stereoregularity index determined by the measurement of the 13C-NMR spectrum, of at least 98%; (4) D value, determined using formula (1) below, from the loss tangents, tan &dgr;0.05 and tan &eegr;10 measured at frequencies, 0.05 rad/sec and 10 rad/sec, respectively, by a melt viscoelasticity measuring device, under a temperature of 230Â° C. and constant strain, and said loss tangent measurement frequencies, of at least 4.0, D=&LeftBracketingBar;log&af;(0.05)-log&af;(10)log&af;(tan&it;â€ƒ&it;Î´0.05)-log&af;(tan&it;â€ƒ&it;Î´10)&RightBracketingBar;(1)and,(5) molecular weight distribution (Mw/Mn), determined by gel permeation chromatography (GPC: solvent: o-dichlorobenzene, measurement temperature: 140Â° C.) of from 6.0 to 20.