Adhesive Compositions of Ethylene-Based and Propylene-Based Polymers

摘要

The present invention is related to adhesive compositions and their applications. In particular, the adhesive compositions described herein comprise an ethylene-based polymer and a propylene-based polymer with varying comonomer content.

主权项

1. An adhesive composition comprising:
(a) an ethylene-based polymer comprising more than 50 wt. % of ethylene-derived units and in the range of 1 wt. % to 49 wt. % of units derived from a first comonomer, said ethylene-based polymer having a Brookfield viscosity of at least 250 mPa·sec measured by ASTM D-3236 at 190° C., a heat of fusion of less than about 250 J/g measured by ASTM D-3418-03, wherein the weight percent measurements are based on the weight of the ethylene-based polymer; (b) a propylene-based polymer comprising more than 50 wt. % propylene-derived units and in the range of 1 wt. % to 49 wt. % of units derived from a second comonomer, said propylene-based polymer having a Brookfield viscosity in the range from 100 mPa·sec to 1500 mPa·sec measured by ASTM D-3236 at 190° C., a heat of fusion of at least 45 J/g measured by ASTM D-3418-03, wherein the weight percent measurements are based on the weight of the propylene-based polymer; wherein said ethylene-based polymer and said propylene-based polymer each have a characteristic time (tc) of at least 0.1 nanoseconds, said characteristic time (tc) in units of nanoseconds is defined by Equation 1:tc=BVDensity×HeatofFusion(Equation1) wherein said BV is the Brookfield viscosity of said ethylene-based polymer or said propylene-based polymer measured by ASTM D-3236 at 190° C. in units of mPa·sec, said Density is the density of said ethylene-based polymer or said propylene-based polymer measured by ASTM D-1505-10 at 23° C. in units of g/cm3, and said Heat of Fusion is the heat of fusion of said ethylene-based polymer or said propylene-based polymer measured by ASTM D-3418-03 in units of J/g.