section_path: Applications/Other important sulfur chemistry
section_name: Other important sulfur chemistry
paragraph_text: Other important sulfur chemistry
  
  Sulfur reacts directly with methane to give carbon disulfide, which is used to manufacture cellophane and rayon. One of the uses of elemental sulfur is in vulcanization of rubber, where polysulfide chains crosslink organic polymers. Large quantities of sulfites are used to bleach paper and to preserve dried fruit. Many surfactants and detergents (e.g. sodium lauryl sulfate) are sulfate derivatives. Calcium sulfate, gypsum (CaSO ·2H O) is mined on the scale of 100 million tonnes each year for use in Portland cement and fertilizers.
  
  When silver-based photography was widespread, sodium and ammonium thiosulfate were widely used as "fixing agents". Sulfur is a component of gunpowder ("black powder").