The Effect of Plasticization of Isoprene Rubber on the Bond Strength of the Brecker Rubber to the Metal Cord. Part 1. Influence of Temperature-Time Conditions of Plasticization and the Role of Rubber Fractions

Abstract

The paper investigates the influence of the plasticization conditions (P) of SKI-3 isoprene rubber on the value of adhesion (A) of the breaker rubber (BR) to the metal cord. P was carried out in a laboratory closed rubber mixer «HFM» at 30 rpm for 30–600 s and a temperature of 30–130 °C. The value of A was determined by the H-method. The equation of the dependence of A on the value of the conditional tensile strength of BR (fр) and the viscosity according to Muni of the rubber mixture (ηm) is obtained. The regions of values of fр and ηm leading to increased values of A is installed. The equations of dependences of the efficiency of contributions (EC) of different fractions of SKI-3 in the value A is obtained. The highest EC has a high–molecular fraction with MM = (500–1000)∙103, and the lowest - low-molecular fraction with MM ˂100∙103. Assumptions are made explaining the EC of each of the four SKI-3 fractions.