| abstract |
A polymer characterized by having a melt tension (MT (g)) substantially equal to or lower than that of a polymer which is substantially equal in repeating units of the backbone and in molecular weight, molecular-weight distribution, and crystallinity and by having a flow activation energy (Ea (KJ/mol)) higher by at least 5 KJ/mol than the Ea value of that polymer. A preferred example of the polymer is one which comprises 50 to 100 mol% repeating units derived from ethylene and 0 to 50 mol% repeating units derived from an a-olefin having 3 to 20 carbon atoms, satisfies a specific relationship between flow activation energy (Ea (KJ/mol)) and a-olefin content (C (wt.%)), and satisfies a specific relationship between melt tension (MT (g)) and melt flow rate (MFR (g/10 min)). This branched polyolefin is excellent in moldability and mechanical strength. |