Vulcanization kinetics of chloroprene rubber

Abstract

Chloroprene rubber was vulcanized with 1,2-ethylenethiourea as accelerator, zinc oxide and magnesium oxide as vulcanizing agents. The non-isothermal vulcanization kinetics of chloroprene rubber was studied by differential scanning calorimetry, the kinetic parameters of vulcanization reaction were calculated by Kissinger and Crane equations, and the kinetics of isothermal vulcanization reaction was studied by vulcanizer method and the apparent activation energy at the thermal vulca-nization stage was calculated. The results showed that the n-order kinetic model could describe the non-isothermal vulcanization process of chloroprene rubber effectively. The apparent activation energy of the vulcanization reaction was 92.78 kJ/mol and the reaction order was 0.93. The isothermal vulcanization process of chloroprene rubber could be divided into 3 stages: scorching stage, thermal vulcanization stage and flat vulcanization stage. The thermal vulcanization stage followed the first-order reaction kinetics and the apparent activation energy of the thermal vulcanization stage was 53.38 kJ/mol.

Keywords

• chloroprene rubber， vulcanization reaction kinetics， non-isothermal differential scanning calorimetry， vulcanizer method， apparent activation energy， reaction order，