Physical properties of blends of LLDPE and an oxidized paraffin wax

The thermal, tensile and Row properties, as well as the surface tension, of blends of linear low-density polyethylene (LLDPE) and oxidized hard paraffin wax were determined. DSC analysis showed only one endothermic peak, despite the fact that pure wax shows two significant peaks. An increase in wax content of the blends hardly changes the onset and peak temperatures, or the specific enthalpies of melting of the blends. The TGA analyses of the blends show that the thermal stability of blends decreases with an increase in wax content, particularly after the 50% stage, since the thermal stability of the wax is much lower than the thermal stability of LLDPE. A small increase in Young's modulus of the blends with an increase in wax content was observed. Wax content was found to have no influence on the yield point (elongation at yield and yield stress) of the blends. An increase in wax content decreases both stress and elongation at break. An increase in Row rate with an increase in wax content of the blends was observed. We also observed that our wax slightly improves the polarity of the blends. There is, however, no direct correlation between the surface tension and wax content in the blends. (C) 2001 Elsevier Science Ltd. All rights reserved.