The Modification of EPDM-Rubber with Maleic Anhydride by Reaction Blending

Abstract

Modification of EPDM rubber was carried out in a corotating twin screw extruder. The effect of process conditions, initial maleic anhydride (MA) and initiator concentration on the total amount of grafted MA was studied. Quantitative infrared analysis and potentiometric titration were used to determine the amount of grafted MA. Within the operating limits of the extruder, process conditions had only little effect on the total amount of grafted MA. Increasing throughput rates at high set temperatures resulted in a small decrease in grafted MA. The initiator concentration had a strong effect on the amount of grafted MA. Higher initiator concentrations led to a higher grafting efficiency. With increasing initial MA concentration, a sharp decrease in grafting efficiency was established.