Quantitative rheological analyses of thermo-oxidative degradation on polyethylene polymers: LDPE, even LLDPE and HDPE
발표자
()
초록
내용
The thermo-oxidative degradation of LDPE was investigated exclusively using rheological measurements. Two thermal treatments were introduced to provoke the thermo-oxidative degradation in LDPE, which are named the annealing process and the aging process. Above the temperature of 170℃, viscosity growth was observed, induced by the thermo-oxidative degradation. Over 190℃, cross-linking in LDPE was determined by the frequency sweep test as gel-like or solid-like behavior (G’ > G”) of the whole measured frequency and by the strain sweep test as critical strain reduction. Using extensional rheology, more LCB creation was observed by more considerable strain hardening in LDPE subjected to thermo-oxidative degradation. For HDPE and LLDPE, viscosity growths by the thermo-oxidative degradation were observed, but at higher temperatures (over 190℃) than LDPE.