Effect of Plasticization of Isoprene Rubber on the Stickiness of its Rubber Compounds. Part 1. Influence of Rubber Fractions, Cohesive Strength and Viscosity of Rubber Compounds

Abstract

 The influence of temperature-time conditions of plasticization (Pl) of isoprene rubber (SKI-3) on the stickiness of the breker rubber mixture is studied. The SKI-3 Pl was carried out in a closed laboratory rubber mixer of the company «HFM» in the temperature range of 30–130 °C and time from 30 to 600 s. Molecular characteristics were determined on a Waters gel chromatograph. It is established that the highest stickiness is achieved at Pl 130 °C and 30 s. It was found that with a decrease in the molecular weight of ultrahigh- and high-molecular fractions of SKI-3, the stickiness of rubber mixtures increases markedly. The low-molecular fraction has the greatest efficiency of increasing stickiness. As a result of the experiment carried out in the work and the calculations performed, it was shown that the stickiness of the rubber mixture is directly proportional to the magnitude of the cohesive strength and inversely proportional to its viscosity.