Indoor and Outdoor Test Results of 205/70R16 Tyres with a Tread Compound Based on Gadolinium-Catalyzed High-cis-1,4-Polyisoprene Rubber

Abstract

The paper presents the results of indoor and outdoor tests of 205/70R16 passenger car tyres in which natural rubber STR20 in the tread compound was replaced by gadolinium-catalyzed high-cis-1,4-polyisoprene rubber (Gd-IR). Indoor tests revealed that the experimental tyre achieves an endurance mileage of 16020 km compared to the reference mileage of 7000 km for the production tyre, and the maximum speed rating reaches 170 km/h versus the rated 160 km/h. Outdoor tests of production and experimental tyres were conducted at tyre testing facilities in accordance with Russian standards and UN ECE Regulations R30 and R117 under near-zero temperatures (Yaroslavl, Tire Testing Center «Vershina») and severe winter conditions (Yakutsk, SVFU Proving Ground). The tests were performed under vehicle operation on compacted snow and smooth ice. Tests at the Yaroslavl facility showed that vehicle acceleration times on snow and ice were statistically equivalent for both production and experimental tyres, whereas the braking distance on snow with experimental tyres was statistically reduced by 2,2 %. Handling performance on snow and ice under near-zero temperatures was statistically equivalent. Tests under severe winter conditions (Yakutsk, snow temperature −10,9 °C) demonstrated that snow traction improved significantly with experimental tyres. A similar statistical conclusion was drawn regarding ice braking distance and vehicle handling on snow and ice.