Rubber
Rubber is a plastic that is largely derived from natural sources and utilized in a modified form. For automobile tyres, Rubber is well identified as material. Rubber relates to a broad class that is known as elastomer and has a property of large extension. An elastomer can extend 100 to 1000% beneath applied force.
Natural rubber, identified as polyisoprene, is acquired from trees as a colloidal dispersion in the milky liquid, termed as rubber latex. This material is extremely soft in its semisolid state and is transformed into sheets by coagulation along with acids and passing among the rolls. This rubber sheet called as crop rubber or smoked sheet doesn't have much strength unless vulcanised at a high temperature for creating cross links among molecular chains. The hardness of rubber depends on degree of cross linking - as higher the cross linking, harder the rubber. Highly vulcanised natural rubber, called as ebonite, is extremely hard. Natural rubber is chlorinated via passing HCl throughout the benzene resolution of natural rubber. The product so acquired is converted in thin adhesive tapes. Hot melt coating for paper is generated from iso-merised rubber dissolved in aromatic or aliphatic compounds. Isomerisation is a procedure whether rubber molecules are prearranged in cyclic form.