Patent ID: 6319577
Filing Date: 2001-11-20
Classification: C08L,Y10T

Abstract:
Sheet or film resulting from calendering, blowing or casting an interpolymer blend comprising a plurality of substantially random interpolymers each interpolymer comprising:(1) from about 1 to about 65 mole percent of polymer units derived from either(a) at least one vinyl aromatic monomer or(b) at least one aliphatic or cycloaliphatic vinyl or vinylidene monomer selected from the group consisting of 5-ethylidene-2-norbornene, 1-vinylcyclohexene, 3-vinylcyclohexene, and 4-vinylcyclohexene, or(c) a combination of at least one of said vinyl aromatic monomer and at least one of said aliphatic or cycloaliphatic vinyl or vinylidene monomer, and(2) about 35 to about 99 mole percent of polymer units derived from ethylene and/or at least one aliphatic alpha olefin having from 3 to 20 carbon atoms; and wherein:(3) the amount of polymer units derived from said vinyl aromatic monomer and/or said aliphatic or cycloaliphatic vinyl or vinylidene monomer in any interpolymer component differs from that amount in another interpolymer component by at least 0.5 mole percent;(4) the amount of polymer units derived from said vinyl aromatic monomer and/or said aliphatic or cycloaliphatic vinyl or vinylidene monomer in the blend is greater than about 19 mole percent; and wherein(5) the observed stress relaxation of the resulting blend is greater than the additive stress relaxation of the of the individual blend components.