Assessment of hindered phenol antioxidants on processing stability of peroxide-cure LDPE by rheology and DSC analysis

摘要

Influence of commercial phenol antioxidants Irganox 300, 1010, 1035, and 1076 on peroxide-cure reaction of low-density polyethylene (LDPE) was evaluated through isothermal dynamic rheological and nonisothermal differential scanning calorimetry (DSC) testing. The results indicated that phenol antioxidants could reduce storage modulus of LDPE completely crosslinked at 175°C while they have a neglectable effect on gel fracture and activity energy of crosslinking reaction. On the other hand, time sweep dynamic rheological test revealed the antioxidants 1035 and 1076 with low molecular weight and low melting point could significantly depress scorch of crosslinkable LDPE at 135°C. The isothermal time sweep dynamic rheology test method was more sensitive than nonisothermal DSC test for characterizing the influence of phenol antioxidants on crosslinking kinetics of peroxide-cure reaction of LDPE.