When the war cut off our principal supply of natural rubber from the East Indies it was necessary to find a substitute in order to carry on the war successfully. For more than twelve years before the war the Du Pont de Nemours Company had made neoprene, the first of our synthetic rubbers. Shortly before we entered the war the Standard Oil Company of Louisiana obtained the German patents for making buna S, the type of rubber now mostly used.
The principal types of synthetic rubbers now manufactured in this country are buna S, buna N, butyl rubber and neoprene. Buna S, butyl rubber and neoprene are the types now being made for our armed forces.
Buna S is made from butadiene and styrene. Butadiene can be made from alcohol and from butylene, a product fractionated from high line gas and light pressure distillate taken from petroleum oil.