IMPROVED POLYETHYLENE RESIN COMPOSITIONS HAVING LOW MI AND HIGH MELT STRENGTH

摘要

Ethylene polymer compositions comprising a high molecular weight high density polyethylene resin and a low density polyethylene resin are disclosed, where the polymer composition has a comparatively high melt strength for a given melt index. The compositions comprise from 25 to 99 percent by weight of the composition of a linear or substantially linear polyethylene polymer having a density of at least about 0.90 g/cc, and an I21 of less than about 20; and from 1 to 25 percent by weight of the composition of a high pressure low density type polyethylene resin having a melt index (I2) less than about 5, a molecular weight distribution greater than about 10, a Mw_abs/Mw_gpc ratio ("Gr") of at least 2.7, and a melt strength at 190°C greater than 19.0 - 12.6*log10(Mi). The compositions of the present invention are particularly well suited for blown film and thermoforming applications.