| 摘要 |
The instant invention is a high-density polyethylene composition, method of producing the same, closure devices made therefrom, and method of making such closure devices. The high-density polyethylene composition according to the present invention comprises (a) a first component comprising a high molecular weight ethylene alpha-olefin copolymer having a density in the range of 0.927 to 0.938 g/cm3, and a melt flow rate (I21) in the range of 4 to 10 g/10 minutes, and (b) a second component comprising a low molecular weight ethylene polymer having a density in the range of 0.960 to 0.975 g/cm3, and a melt index (I2) in the range of 100 to 1200 g/10 minutes; and wherein the high-density polyethylene composition has a melt index (I2) in the range of from 2 to 10 g/10 minutes, a density in the range of from 0.950 to 0.960 g/cm3, and a flow direction shrinkage to cross flow direction shrinkage ratio in the range of from 2 to 3.2, and an environmental stress crack resistance (ESCR) (F50) according to ASTM D-1693, condition B at 50° C., and using 10 percent Branched Octylphenoxy Poly (Ethyleneoxy) Ethanol, in the range of equal to or greater than 50 hours. |
