Crystallization of a low molecular weight polyethylene and paraffins undera temperature gradient

A low molecular weight polyethylene (PE) and even-number paraffins were cry stallized under a temperature gradient. Highly oriented crystalline texture s were developed by the temperature slope crystallization. The in situ crys tallizing surface was observed by an optical microscope and X-ray diffracti on. Polyethylene has a b-axis orientation in which the lamellar normal and crystalline c-axis are perpendicular to the temperature gradient. On the co ntrary, in the even-number paraffins, both axes are parallel to the tempera ture gradient. The results of the in situ measurements and the crystalline orientation are compared and discussed for both cases.