An ethylene (co)polymer of the present invention is a (co)polymer with excellent moldability and mechanical properties and either an ethylene homopolymer or a copolymer of ethylene and an α-olefin of 4 to 20 carbon atoms. The (co)polymer has methyl branches measured by
13
C-NMR less than 0.1 in number per 1,000 carbon atoms and Mw/Mn measured by GPC not lower than 1.8 and lower than 4.5. The (co)polymer is either an ethylene homopolymer or a copolymer of ethylene and an α-olefin of 3 to 20 carbon atoms. The melt tension (MT) and the swell ratio (SR) satisfy the relation; log(MT)>12.9−7.15×SR; and the intrinsic viscosity ([η]) and the melt flow rate (MFR) satisfy the relation; [η]>1.85×MFR
−0.192
in the case of MFR<1 and the relation; [η]>1.85×MFR
−0.213
in the case of MFR≧1. Such an ethylene (co)polymer can be usable for various molding applications and especially suitable for pipes.
本发明的
乙烯(co)聚合物是一种具有优异的成型性和机械性能的(co)聚合物,可以是
乙烯均聚物或
乙烯和4至20个碳原子的α-烯烃的共聚物。该(co)聚合物在13C-NMR下测量,每1,000个碳原子的甲基支链少于0.1个,并且在
GPC下测量的Mw/Mn不低于1.8且低于4.5。该(co)聚合物可以是
乙烯均聚物或
乙烯和3至20个碳原子的α-烯烃的共聚物。熔融张力(
MT)和膨胀比(SR)满足关系式; log(
MT)>12.9−7.15×SR; 内禀粘度([η])和熔体流动速率(MFR)满足关系式; 当MFR<1时,[η]>1.85×MFR−0.192,当MFR≧1时,[η]>1.85×MFR−0.213。这种
乙烯(co)聚合物可用于各种成型应用,特别适用于管道。