Patent ID: 6462136
Filing Date: 2002-10-08
Classification: C08F,C08L

Abstract:
An ethylene copolymer (a) obtained from ethylene and an &agr;-olefin of 3 to 20 carbon atoms and satisfying the following requirements (i) to (v):(i) said copolymer comprises 40 to 99% by mol of recurring units derived from ethylene and 1 to 60% by mol of recurring units derived from an &agr;-olefin of 3 to 20 carbon atoms, (ii) the ratio (Mz/Mw) of a Z average molecular weight (Mz) to a weight-average molecular weight (Mw), each molecular weight being measured by gel permeation chromatography, is in the range of 10 to 30, and said ratio (Mz/Mw) and the ratio (Mw/Mn) of a weight-average molecular weight (Mw) to a number-average molecular weight (Mn), each molecular weight being measured by gel permeation chromatography, satisfy the following relation (Mz/Mw)>(Mw/Mn), (iii) the intrinsic viscosity, as measured in decalin at 135Â° C., is in the range of 0.5 to 4 dl/g, (iv) the ratio (&eegr;*0.01/&eegr;*8) of a melt viscosity (&eegr;*0.01) at a shear rate of 0.01 rad/sec, as measured at 190Â° C., to a melt viscosity (&eegr;*8) at a shear rate of 8 rad/sec, as measured at 190Â° C., and the intrinsic viscosity (&eegr;) satisfy the following relation (1) (&eegr;*0.01/&eegr;*8)&gE;0.843Ã—(&eegr;)+1.0 â€ƒâ€ƒ(1), and (v) the absolute value of an activation energy (Ea) of a shift factor of melt viscoelasticity is not more than 4Ã—104 J/molÂ·K.