Curing (chemistry) Curing (chemistry) Curing is a term in polymer chemistry and process engineering that refers to the toughening or hardening of a polymer material by cross-linking of polymer chains, brought about by electron beams, heat, or chemical additives. When the additives are activated by ultraviolet radiation, the process is called UV Cure. In rubber, the curing process is also called vulcanization. Five types of curing systems are in common use. They are: Despite the wide variety of thermoset resin formulations (epoxy, vinylester, polyester, etc.), their cure behavior is qualitatively identical. The resin viscosity drops initially upon the application of heat, passes
Sulfur dye combining aromatic compounds and sulfur sources. The most important member of the class is Sulfur Black 1. It is produced by the reaction of 2,4-dinitrophenol and sodium sulfide in hot water. Like many sulfur dyes, details on the chemical reactions are poorly understood. It is accepted that the sulfide reduces the nitro groups to aniline derivatives, which are thought to form indophenol-containing intermediates that are further crosslinked by reaction with sulfur. The result are insoluble, high molecular weight species. Sulfur Black 1 is imperfectly understood, and the material is probably heterogeneous. It is speculated to be a polymer consisting of