Ethyltriphenylphosphonium Acetate, also known as ETPAAC, ETPAACc and TEPA, is a colourless to slightly yellow liquid with the chemical formula C22H23O2P. This quaternary phosphonium salt is available in a 70% by-weight solution in methanol. Notably, one mole of acetic acid is bound to each mole of ETPAAC. Furthermore, the material is mainly used for advancing and curing phenolic-based epoxy resins and serving as a phase transfer catalyst. Compared to amines, imidazoles, and quaternary ammonium salts, Ethyltriphenylphosphonium Acetate has considerably better latency and thermal stability. Further, it offers a low odour, minimal colour formation and controlled reactivity.
