Elastomer

The term elastomer is often used interchangeably with the term rubber, and is preferred when referring to vulcanisates. They are amorphous polymers existing above their glass transition temperature, so that considerable segmental motion is possible. At ambient temperatures rubbers are thus relatively soft (E~3MPa) and deformable. Their primary uses are for seals, adhesives and molded flexible parts.

Elastomers are usually thermosets (requiring vulcanization) but may also be thermoplastic. The long polymer chains cross-link during curing and account for the flexible nature of the material. The molecular structure of elastomers can be imagined as a 'spaghetti and meatball' structure, with the meatballs signifying cross-links.

Examples of elastomers;

• Rubber
• Buna rubber
• Silicone RTV
• Viton®
• Neoprene
• Santoprene
• Fluorosilicone Rubber
• EPDM rubber
• Polyurethane rubber
• Nitrile rubber