Modeling on the kinetics of an EPDM devulcanization in an internal batch mixer using an amine as the devulcanizing agent

The use of amines and the application of mechanical force (shear) in rubber devulcanization have been reported in the literatures. In this paper, the devulcanization of ethylene propylene diene rubber (EPDM) is conducted in a Brabender batch mixer using hexadecylamine (HDA) as the devulcanizing agent. Considering the complexity of the compound and the limitations of the analyses techniques for crosslinked systems, an engineering approach to model a devulcanization process of EPDM material is proposed. An engineering kinetic model has been derived by fitting a large number of experimental data with several models based on simple kinetic considerations. Rate determining parameters such as temperature, shear rate, reactant concentrations and time are included in the model. The model obtained covers all the phenomena happening during the devulcanization, without distinguishing them on the molecular level.