STUDY OF THE EFFECT OF ADDITIVES OF LIQUID RUBBERS ON THE PERFORMANCE OF LOW-VINYL STYRENE-BUTADIENE RUBBERS

Abstract

The influence of polybutadiene liquid rubbers (LR) type and dosages on the performance of styrene-butadiene rubber (SSBR) and rubber compounds and vulcanizates based on it has been studied. LR – non-functional polybutadiene liquid rubber (LR1) and liquid polybutadiene functionalized with siloxane groups (LR2) in an amount 1, 3, 5 % of the mass were introduced into SSBR at the stage of its preparation in the form of a solution in a three-component inert organic solvent. Styrene content and 1,2- and 1,4-units in the butadiene part of SSBR, molecular weight characteristics, in particular, M_w/M_n, the tangent of the angle of mechanical losses tgδ at 0 and +60 °C, characterizing the performance properties of tires, and the difference in the real parts of the dynamic shear modulus at deformations of 50 and 1% Δ (G'_1% – G'_50%), characterizing the Payne effect, Schopper-Schlobach abrasion, Mooney viscosity, as well as standard physical and mechanical properties of rubber compounds and vulcanizates were estimated. Most of the characteristics practically do not change; however, there is a tendency to a slight increase in M_w/M_n, a decrease in tgδ at +60 °C and, most importantly, the Mooney viscosity. These slight changes indicate a certain plasticizing effect of the studied LR and the prospects of the chosen direction of research aimed at improving processability of SSBR.