Use of Benzene-1,3-Bis(Sulfonyl)Azide as Crosslinking Agent of TPVs Based on EPDM Rubber—Polyolefin Blends

Abstract

Abstract The use of innovative crosslinking agents for the preparation of thermoplastic vulcanizates (TPVs) is investigated. In this preliminary study, the most common TPV systems, based on polypropylene (iPP) and ethylene—propylene—diene terpolymer rubber (EPDM) blends, are studied. Among typical vulcanization agents, only the peroxides are able to crosslink saturated elastomers, however, they present the disadvantage that give rise to chain scission of the thermoplastic matrix. For this reason, the main goal of the present study is to investigate a new vulcanization agent for elastomeric matrices, which also permit the dynamic vulcanization process in their blends with polyolefins. This agent is based on a diazide derivative, benzene-1,3-bis(sulfonyl)azide that, for the specific behavior of the sulfonyl azide group, allows its interaction with the carbon—hydrogen bonds of the elastomeric phase and of the polyolefin. The study includes the dynamic vulcanization of PP—EPDM blends and their rheological, mechanical and thermal characterization. A comparison with traditional TPVs prepared with sulfur as vulcanization agent is also presented.