Extrudable styrenic block copolymer compositions containing a metallocene polyolefin

Abstract

An extrudable elastomeric composition for making elastic films having a recoverable energy greater than 60%, the composition includes an elastomeric block copolymer, a metallocene polyolefin, and a tackifying resin. The composition optionally may contain a crystalline polyolefin and an extending oil.

Claims

1. An elastic film having recoverable energy greater than 60%, comprising:

from 25% to 70% by weight of a block copolymer having at least two monoalkenyl arene blocks separated by a hydrogenated conjugated diene block;

from 15% to 60% by weight of the polymer components of an elastomeric polyolefin having a density from 0.86 to 0.91 and a molecular weight distribution having a polydispersity less than 3, wherein the elastomeric polvolefin is produced by polymerizing ethylene and from 8% to 30% by weight of an.alpha.-olefin comonomer having from 4 to 12 carbon atoms with a metallocene catalyst;

from 0% to 25% by weight of a crystalline polyolefin; and

a from 15% to 28% by weight of a tackifying resin.

2. The film of claim 1, wherein the block copolymer has the structure styrene-poly(ethylene-butylene)-styrene.

3. The film of claim 1, further comprising an extending oil.

4. The film of claim 1, wherein the comonomer in the elastomeric polyolefin is butene.

5. The film of claim 1, wherein the comonomer in the elastomeric polyolefin is octene.