Cross-Link Density, Mechanical and Thermal Properties of Chloroprene Rubber Cross-Linked with Silver(I) Oxide

Abstract

The purpose of this work was to cross-link chloroprene rubber (CR) with silver(I) oxide (Ag2O) and to investigate the properties of the obtained vulcanizates. Silver(I) oxide was chosen as an alternative to zinc oxide (ZnO), which is part of the standard CR cross-linking system. The obtained results show that it is possible to cross-link chloroprene rubber with silver(I) oxide. This is evidenced by the determined vulcametric parameters, equilibrium swelling and elasticity constants. As the Ag2O content in the composition increases, the cross-link density of the vulcanizates also increases. However, the use of 1 phr of Ag2O is insufficient to obtain a suitably extensive network. Exclusively, the incorporation of 2 phr of Ag2O results in obtaining vulcanizates with great cross-link density. The obtained compositions are characterized by good mechanical properties, as evidenced by high tensile strength. The performed thermal analyses—differential scanning calorimetry (DSC) and thermogravimetry (TGA) allowed us to determine the course of composition cross-linking, but also to determine changes in their properties during heating. The results of the thermal analysis confirmed that CR can be cross-linked with Ag2O, and the increasing amount of oxide in the composition increases the degree of cross-linking of vulcanizates. However, the amount of Ag2O in the composition does not affect the processes occurring in the heated vulcanizate.