Rubber is a flexible substance produced from the milkweed of some tropical plants or from petrol and natural gas. Rubber made from tree milkweed is called natural rubber and rubber made from petrol is called synthetic rubber. In the whole world, 15 million tons of rubber is produced annually. Approximately one third of this is natural rubber and the rest is the synthetic rubber produced from petrol with chemical substances. APPLICATION FIELDS OF RUBBER: Rubber usage has shown an increase with the development of road transportation. Rubber is used primarily for tires of bicycles as well as cars, trucks, planes, and road diggers. In addition to this, rubber is used in the production of various products such as water repellant clothes, shoes, gloves, medical equipment, upholstery materials, toys and inflatable beds. CHEMICAL SUBSTANCES ADDED TO RUBBER CAN BE LISTED AS THE FOLLOWING: Plasticizers. Softeners. Substances to delay aging. Substances to make it cheap. Durability and hardness enhancers. Dyes. Substances to speed up or slow down reactions.