Modhnu airionna rubair tri oibriu ceimiceach a dheanamh air le sulfar (ach amhain rubair shinteiseacha airithe). Cruthaionn se seo trasnaisc idir na macramoilini rubair. Is feidir ceimiceain eile a usaid chun na himoibrithe seo a bhrostu. Proiseas e seo a d'fhionn Charles Goodyear i 1839 . Feabhsaionn se an neart teanntachta , an leaisteachas , cruas an dromchla is a fhriotaiocht scriobtha. [1]