Rheologic studies on chemical cross-linking kinetics for LDPE

Crosslinking reaction of LDPE resin in the presence of dicumyl peroxide (DCP) was studied by isothermal rheological measurements at different temperatures and non-isothermal differential scanning calorimetry (DSC) technique with different heating rates. The kinetic parameters of crosslinking reaction were calculated by both rheological and DSC measurements. The results reveal that with the increase of DCP contents, the apparent activation energy, E _a, ranges from about 140 kJ/mol to 170 kJ/mol and the order of crosslinking reaction, `(n)]\bar n, approaches unity. The influence of measurement frequency, ω, on crosslinking reaction was also investigated. It can be found that `(n)]\bar n does not change with the increase of ω, and E _a decreases slightly with the increase of ω.