Thermogravimetric analysis of compatibilized blends of low density polyethylene and poly(dimethyl siloxane) rubber

The thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis of compatibilized blends of low density polyethylene (LDPE) and poly(dimethyl siloxane) rubber (PDMS) in the proportion of 50:50 containing different proportions of ethylene methyl acrylate co-polymer (EMA) as compatibilizer have been studied. EMA acts as a chemical polymeric compatibilizer for the binary blend system of LDPE and PDMS, the proportion of which varied from 0 to 15 wt.%. The TG and DTG of the blends show that the thermal degradation takes place in two stages, where as neat LDPE shows a three stage degradation and neat EMA and PDMS show only single stage degradations respectively. The activation energies at 10% degradation have been determined using Freeman and Carroll's method and found to be maximum (171 kJ/mol) for the blend containing 6 wt.% of EMA. Half life periods at 200 °C have been evaluated by the Flynn and Wall method and found to be maximum for the blend containing 6 wt.% of EMA.