Thermally stimulated current study of low-density polyethylene with and without inorganic filler

By measuring thermally stimulated current (TSC) spectra at various poling parameters in low-density polyethylene with and without filler (kaolin), (f-LDPE and LDPE), we show that the TSC spectra have a significant distinction. By analysing the change of peak current and temperature, and activation energy with poling field, we can see that TSC in f-LDPE comes from dipole relaxation due to polar groups in filler catching electrons injected at high field, rather than detrapping of captured electrons in interfacial trap between filler and polymer. So this filler, as a deeper trap stemming from its polar group or interface, plays the role of electron accepter. TSC spectra of LDPE possess the marked characteristic of electron release from traps in amorphous-crystalline interface or crystalline region