Novel use for sulfur

02 June 2013 - Acid rain cleanup

Remember acid rain? Chemists found a way to clean up the mess with the invention of hydrodesulfurization but now we are stuck with tons of elemental sulfur we do not know what to do with. The planet needs only that much sulfuric acid. Nice to know Woo Jin Chung and 17 of his best friends propose a way to get rid of this sulfur: as a new polymer material (DOI).
The quick summary: elemental sulfur is mixed with 30% 1,3-diisopropenylbenzene (DIP) and heated to 180°C. This forms a copolymer with glass transition temperature 17°C. With slightly more DIP the material is soluble in non-polar solvents. GPC reveals a large degree of branching (PD = 2.7). The process is called inverse vulcanisation because in regular vulcanisation the amount of sulfur used is very small rather than very large. The chemical process is ring-opening polymerisation with S8 diradicals. As a proof of concept the new material was created as a micropatterned film. Only thing still to find out, according to the researchers: why is the new material red?