| 摘要 |
The present invention relates to an orientated polyolefin composition comprising an olefin (co)polymer having a weight average molecular weight (Mw) from 30,000 to 1,000,000 and a high molecular weight tail extending to molecular weights above 1,000,000, and has a microstructure which is substantially parallel chain extended cores of the component polymer(s) and associated lamellar overgrowths extending in planes normal to the cores. The lamellar overgrowths on adjacent cores intermesh and are capable of sustaining a haul off tension of at least 10 MPa without breaking during its extrusion. …<??>The orientated polyolefin composition is produced by extruding an olefin copolymer through a die under a pressure of about 5-10 MPa, at a temperature above the self-blocking temperature thereof and by hauling off the extrudate at a tension of at least 10 MPa without breaking. The extrudates so produced have a high modulus. |
