SBR compounds containing ammonium derivatives as neutral analogues of the oligoamidephosphates were studied with respect to their vulcanization characteristics and mechanical properties. Several differences between the effects of the neutral ammonium derivatives and the oligoamidephosphates were discovered, which may be connected with the different pHs of these products. As in the case of isoprene rubber compounds, the neutral products showed increased efficiency in comparison with the oligoamidephosphates. They offer the possibility of a four-fold reduction of the optimum cure time and partial replacement of the base sulphenamide accelerator. All SBR compositions containing neutral ammonium derivatives (NADs) were relatively well crosslinked and had cure characteristics and mechanical properties equal to, or better than, the corresponding compositions without neutral ammonium derivatives, even in the cases when the NAD amount was predominant. The results of our experiments give reason to assume that NADs participate in the vulcanization process with the formation of a different number of chemical bonds of various types. The NADs probably affect some physical interactions also.
