Polyisoprene, polymer of Isoprene (C5H8) that is the primary chemical constituent of natural rubber. Depending on its molecular structure, polyisoprene can be a resilient, elastic polymer (elastomer), as in the case of natural rubber and isoprene rubber, or a tough, leathery resin, as in the case of natural and synthetic balata or gutta-percha.
Typical applications include anti-vibration mounts, drive couplings, tires,springs, bearings, rubber bands, and adhesives. The typical working temperature range is -50°C to +100°C.