Application of hygrothermally decomposed polyurethane in rubber recipes Part 2–Influence of hygrothermally decomposed polyester–urethane on cure characteristics and viscoelastic behaviour of styrene/butadiene rubber

Abstract

Hygrothermally decomposed polyester–urethane (HD PUR) was mixed at concentrations up to 20 pphr with a styrene/butadiene rubber (SBR), using an efficient vulcanisation system. Changes in the cure behaviour were followed by vulcametry, plate–plate rheometry, and differential scanning calorimetry. It was found that the degree of crosslinking was increased by the incorporation of HD PUR, which acts as an accelerator in SBR stocks. Increasing crosslinking resulted in higher stiffness and strength and was accompanied by a reduction in elongation at break and swelling index.