Thermal properties of uncross-linked and cross-linked LLDPE/wax blends

Thermal properties of cross-linked and uncross-linked LLDPE/wax blends were investigated. The blends were prepared through thorough mixing of the powdery ingredients, followed by 10 min pressing at 180 degrees C. The extent of cross-linking was determined through gravimetric analysis of the gel content of the samples. The thermal properties were determined with a differential scanning calorimeter (DSC), while a thermogravimetric analyzer (TGA) was used to determine the thermal stability of the samples. The analyses of cross-link density of the samples indicated that the wax is grafted onto the LLDPE chains at higher wax concentrations. The DSC results indicated that LLDPE and wax are miscible in the crystalline phase, and that cross-linking reduces polyolefin crystallinity, The TGA results indicated a reduction in thermal stability of the blends with increasing wax portion. (C) 2000 Elsevier Science Ltd. All rights reserved.