Recycling of vulcanized EPDM-rubber: mechanistic studies into the development of a continuous process using amines as devulcanization aids

The objective of this project was to prove the feasibility of production scale recycling of EPDM-rubber, based on the outcome of a former project, by developing a continuous process for mechano-chemical reclaiming of EPDM-rubber waste, using amines as devulcanization aids. In order to prove this feasibility, a great many variables needed to be screened from the perspective of the rubber compound composition as well as from the perspective of process development. This research was a joint project with the University of Groningen, Department of Chemical Engineering, and their research was focused on the development of the continuous reclaiming process. The research described in the present thesis is focused on the material: influence of the rubber compound composition on the process efficiency and product quality, optimization of the devulcanization aid and application studies. Application development focused on the use of such reclaimed EPDM as a raw material for roof-sheeting. This is a material which is commonly vulcanized to a low extent, in order to obtain optimal flexibility of the material. It was the preferred application for this study, as a certain loss in vulcanization efficiency of the EPDM could be tolerated. The potential size of this market is very large, thereby providing an outlet for large amounts of recycled EPDM-rubber of various origins: automotive as well as building and construction profiles