ElASTomere

An elastomere, or elastomer, is a polymer with the ability to undergo large reversible deformations and to recover its original shape after removal of stress. This elasticity typically arises from a three‑dimensional network of long polymer chains that are cross‑linked, either chemically (for example by vulcanization with sulfur or by peroxides) or by physical entanglements. In many cases elastomers are cross‑linked to form thermoset networks, though thermoplastic elastomers (TPEs) combine elastomeric behavior with thermoplastic processing.

Natural rubber is polyisoprene obtained from latex, while synthetic elastomers include styrene–butadiene rubber (SBR), acrylonitrile–butadiene rubber (NBR), polybutadiene rubber (BR), neoprene, silicone (polydimethylsiloxane), and fluorocarbon elastomers (FKM), among others. The properties of elastomers are strongly influenced by cross‑link density and the chemical nature of the chains. Elastomers typically exhibit low modulus, high elongation at break, and good resilience, with service temperatures and chemical resistance varying by type. Tg (glass transition temperature) is usually below room temperature for many elastomers, enabling flexibility at ambient conditions.

Processing and applications: elastomers are compounded with fillers (e.g., carbon black or silica), initiators, and other additives, then cured through vulcanization or processed as recyclable thermoplastic elastomers. Common uses include tires, seals and gaskets, hoses, belts, vibration dampers, and medical devices (notably silicone elastomers).

Aging and degradation factors include ozone, UV exposure, heat, and chemical attack, which can cause cracking, loss of elasticity, or swelling in solvents.