Humans have not used rubber for a very long time, but demand for rubber has grown explosively since modern times. Rubber is an essential material in daily life—it is literally everywhere. Without rubber, we could not erase pencil marks, faucets would leak like fountains, and cars could not run at all. Clearly, rubber is indispensable to modern life.
But do we really understand rubber?
Rubber is a highly elastic polymer material with reversible deformation. It is flexible at room temperature, can undergo large deformation under a small external force, and returns to its original shape once the force is removed. This elasticity comes from crosslinked molecular chains, which also give rubber good physical, mechanical properties and chemical stability. As the basic raw material of the rubber industry, rubber is widely used to make tires, hoses, belts, cables, and many other rubber products.
Rubber is an amorphous polymer with a low glass transition temperature and very high molecular weight—often greater than several hundred thousand. These structural features give rubber its excellent performance, which is why it is so widely relied upon.
By Raw Material
• Natural Rubber: Made from natural latex; some non-rubber components in latex remain in the solid natural rubber.
• Synthetic Rubber: A man-made high-elastic polymer, and one of the three major synthetic materials.
By Physical Form
• Solid Raw Rubber: Block rubber for conventional processing.
• Latex: Colloidal aqueous dispersion of rubber.
• Liquid Rubber: Low-molecular-weight rubber, usually viscous before vulcanization.
• Powdered Rubber: Latex processed into powder for easier mixing.
Thermoplastic rubber, developed in the 1960s, can be formed like thermoplastics without chemical vulcanization.
By Application
• General-Purpose Rubber: Good overall performance, widely used in most products.
• Special-Purpose Rubber: Designed for specific properties. For example, nitrile rubber is oil-resistant; chloroprene rubber is aging-resistant.
Rubber is a truly valuable material. Until new alternative materials are developed, rubber will remain a fundamental industry supporting economic growth for a long time to come.
