Polyethylene blend composition having a reduced chill roll buildup during extrusion process

摘要

The instant invention provides a polyethylene blend composition having reduced chill roll buildup during extrusion process, and films and coating layers made therefrom. The polyethylene blend composition according to the present invention provide reduced chill roll buildups during extrusion process, and comprises: (a) from 60 to 95 percent by weight of a linear polyethylene composition comprising less than or equal to 100 percent by weight of the units derived from ethylene, and less than 15 percent by weight of units derived from one or more α-olefin comonomers; wherein said linear polyethylene composition has a density in the range of from 0.917 to 0.975 g/cm3, a molecular weight distribution (Mw/Mn) in the range of from 1.70 to 3.62, a melt index (I2) in the range of from 2 to 50 g/10 minutes, and a vinyl unsaturation in the range of from less than 0.06 vinyls per one thousand carbon atoms present in the linear polyethylene composition; and (b) from 5 to 40 percent by weight of a low density polyethylene composition (LDPE) having a density in the range of from 0.915 to 0.930 g/cm3, and a melt index (I2) in the range of from 0.4 to 10; wherein the polyethylene blend composition has a density in the range of 0.917 to 0.960 g/cm3 and a melt index (I2) in the range of from 2 to 30 g/10 minutes.

主权项

1. A polyethylene blend composition having reduced chill roll buildup during extrusion process comprising:
(a) from 60 to 95 percent by weight of a linear polyethylene composition comprising; less than or equal to 100 percent by weight of the units derived from ethylene; less than 15 percent by weight of units derived from one or more α-olefin comonomers; wherein said linear polyethylene composition has a density in the range of from 0.917 to 0.975 g/cm3, a molecular weight distribution (Mw/Mn) in the range of from 1.70 to 3.62, a melt index (I2) in the range of from 2 to 50 g/10 minutes, and vinyl unsaturation in the range of from less than 0.06 vinyls per one thousand carbon atoms present in the linear polyethylene composition wherein said linear polyethylene composition is a linear low density polyethylene (LLDPE), a high density polyethylene (HDPE), or combinations thereof; (b) from 5 to 40 percent by weight of a low density polyethylene composition (LDPE) having a density in the range of from 0.915 to 0.930 g/cm3, and a melt index (I2) in the range of from 0.4 to 10 g/10 minutes; wherein the polyethylene blend composition has a density in the range of 0.917 to 0.920 g/cm3 and a melt index (I2) in the range of from 2 to 30 g/10 minutes and wherein said polyethylene blend composition produces less than 0.06 grams of contamination, measured according to a Plate Out Test.