Effects of pressure and temperature on the melt density and the melt flow rate of LDEP and glass bead-filled LDPE composite

The effects of pressure and temperature on the melt density (rho(m)) and th e melt flow rate (MFR) of the low-density polyethylene (LDPE) and a glass b ead-filled LDPE composite (LDPE/GB) have been investigated using a capillar y plastometer. It was discovered that the MFR of the melts increased as an exponential law function with a rise in temperatures and increased as a qua dratic function with increasing pressure; the rho(m) of the melts increases non-linearly with increases in pressure and decreased approximately linear ly with increases in temperature. For the same temperature, the values of t he MFR for LDPE/GB are somewhat lower than those of the unfilled LDPE when the pressure is not too high. The relationship between the composite melt d ensity, the glass bead density and the unfilled LDPE melt density obeys a s imple mixing rule. (C) 1998 Elsevier Science S.A. All rights reserved.