Wide-angle X-ray scattering studies on polyethylene at low temperatures

Summary Linear polyethylene (Lupolen 6041 D) and a polyethylene fraction (PE 2000) were investigated by WAXS at temperatures 8 K50 K and then to lower temperatures a decrease is observed. This is explained by the decrease of the thermal expansion coefficients. For PE 2000 for some reflections a minimum in the integral widths at T38 K occurs. The explanation of this effect is given by the occurence of a stress induced martensitic transformation (orthorhombic to monoclinic) of part of the material. The corresponding weak reflections are observed.