Influence of Carbon Black Modified with Phospholipid Concentrate on the Properties of Synthetic Polyisoprene Based Rubber Compounds

Abstract

The influence of modification of carbon black (CB) with phospholipid concentrate (PhLC) on the vulcanization characteristics of rubber compound, physico mechanical properties and heat resistance of vulcanizates based on synthetic isoprene rubber SKI 3 was studied. Standard physico mechanical tests were used in the research. The modification of CB with PhLC was carried out in carbon tetrachloride at ratio CB : PhLC = 4 : 1. To obtain PhLC dosages of 3, 5, and 7 phr (parts per hundred rubber), mixtures of modified and unmodified CB were used. It was shown that the modification of CB with PhLC has practically no effect on the Mooney viscosity of the rubber compounds, but significantly accelerates the vulcanization process: the optimum vulcanization time t90 decreases from 12,43 to 7,92 min at a PhLC dosage of 5 phr. The optimal PhLC content was found to be 5 phr, at which the tensile strength increases by 9,4 %, the elongation at break increases by 10,5 %, and the Shore A hardness rises to 9,5%. After thermo oxidative aging, the best retention of properties was exhibited by the sample containing 5 phr of PhLC. The obtained results allow recommending the modification of CB with PhLC for accelerating vulcanization and improving the elastic strength properties of rubbers based on SKI 3.