Glossary of Rubber Terms

Definitions of Rubber Terms and Terminology

Compound: An uncured rubber composition including the rubber, oil, carbon black, curatives, etc.
Compression Set: The decrease in thickness of a test specimen 30 minutes after removal from a device in which the specimen has been subjected to compression deformation.
Cure: An irreversible process during which a rubber compound through a change in its chemical stucture (cross–linking, for example), becomes less plastic and more resistant to swelling by organic liquids and elastic properties are conferred, improved or extended over a greater range of temperature. Cure and vulcaniztion are interchangeable terms as they share the same definition.
Durometer: An instrument for measuring the hardness of rubber and plastic.
Elongation: The percentage of original length to which a rubber compound is stretched.
Hardness: The relative resistance of rubber to indentation. Usually a Shore A2 Hardness tester (Durometer) is used to measure hardness.
IMDS: The International Material Data System (IMDS) is a collective, computer-based material data system for OEMs (Original Equipment Manufacturer) to manage relevant environmental aspects of the different parts in vehicles. More info >
Polymer: Many monomer units chemically linked together in repeating structural units. Rubber polymers available at WARCO BILTRITE include: Neoprene, Butyl, EPDM, Nitrile (Buna–N), Natural Rubber, SBR, Silicone, and Fluoroelastomer (including Viton®). Get more information about these rubber polymers >
Polymerization: Process of linking two or more molecules to form a new molecule having different properties.
RoHS: The Restriction of Hazardous Substances (RoHS) Directive 2002/95/EC was adopted in February 2003 by the European Union. This directive restricts the use of six hazardous materials in the manufacturing of various types of electrical and electronic equipment. More info >
Synthetic Rubber: An elastic substance produced from monomers such as butadiene, styrene and isoprene. Because of superior performance (tread wear, resistance to groove cracking, lower cost) synthetic rubbers have largely replaced natural rubber.
Tensile Strength: The maximum stress expressed on pounds per square inch (mega pascal) of a cured rubber compound.
Vulcanization: An irreversible process during which a rubber compound through a change in its chemical stucture (cross–linking, for example), becomes less plastic and more resistant to swelling by organic liquids and elastic properties are conferred, improved or extended over a greater range of temperature. Cure and vulcaniztion are interchangeable terms as they share the same definition.