Polymer such as rubber, suberin, melanin and lignin. Naturally occurring polymers such as cotton, starch and rubber were familiar materials for years before synthetic polymers such as polyethene and perspex appeared on the market. Many commercially important polymers are synthesized by chemical modification of naturally occurring polymers. Prominent examples include the reaction of nitric acid and cellulose to form nitrocellulose and the formation of vulcanized rubber by heating natural rubber in the presence of sulfur. Ways in which polymers can be modified include oxidation, cross-linking and endcapping. Especially in the production of polymers the gas separation by membranes has acquired increasing
Union Sulphur Company Union Sulphur Company The Union Sulphur Company was an American sulfur mining corporation founded in 1896 by the famous inventor Herman Frasch. It utilized the Frasch Process to extract previously inaccessible sulfur deposits located beneath swampland in Louisiana. The Union Sulphur Company dominated the world sulfur market until its patents expired in 1908. Its success led to the development of the present-day city of Sulphur, Louisiana. After its sulfur patents expired, the company transitioned into oil and natural gas production and was renamed the Union Sulphur & Oil Company and later the Union Oil & Gas Corporation. During World War