| 摘要 |
PCT No. PCT/EP96/02801 Sec. 371 Date Jul. 28, 1998 Sec. 102(e) Date Jul. 28, 1998 PCT Filed Jun. 26, 1996 PCT Pub. No. WO97/10941 PCT Pub. Date Mar. 27, 1997A continuous method of extruding an oriented plastic article of improved strength. A chemically reactive polymer, monomer or other compound is included in the matrix material(s) and a (multilayer) parison is extruded or melt formed having built-in thermoplastic orientation caused by shear or caused by elongational flow. A reaction can be activated in the molten state thereof by additional heat resulting in a cross-linked structure or at least the mobility of the molecules being reduced, resulting in a longer relaxation time which makes the freezing of permanent orientation possible. The soft matrix can be stretched while still hot in the hoop and/or axial direction. Then, the product thus obtain is calibrated and cooled in an oriented state. |
