CROSS-LINKING OF SATURATED ELASTOMERS WITH DI-AZIDES. PART II: MECHANISTIC STUDY

In the first part, one di-sulfonyl azide: 1,3BDSA, and two di-azidoformates: GDAF and 4,4'DAF, were selected and extensively investigated as curing agents for EP(D)M rubbers. Although the mechanical properties of the vulcanizates vary significantly with the particular di-azide used, all of them act as effective curing agents compared to a peroxide/coagent curing system. To explain the differences in properties as well as to obtain a deeper understanding of the reaction mechanism, model compound experiments are performed with 4-methylheptane as substitute for the saturated ethylene propylene copolymer rubber backbone. Using gas chromatography/mass spectrometry and high performance liquid chromatography/mass spectrometry as analytical tools, a basic understanding of the reaction mechanisms between sulfonyl azide and azidoformate functionalities and saturated hydrocarbons is obtained. [doi:10.5254/1.3577546]