Abstract: | A study of the production of biaxially oriented polyethylene tubes by the die-drawing process was carried out examining the effects of draw temperature, haul-off speed, and mandrel size. The effect of postmandrel cooling was also studied. A range of biaxially oriented tubes of various draw ratios and thicknesses were produced. The Young's modulus and the tensile strength of biaxially drawn samples show considerable enhancement in both directions over the isotropic material. Biaxially drawn samples show remarkable improvement in their impact strength over the isotropic material. The crystalline orientation and texture of these samples are characterized using wide-angle X-ray scattering pole figure analysis. © 1996 John Wiley & Sons, Inc. |