Synthesis and properties of green sustainable carbonate-type nonionics containing polyoxyethylene chains.

A series of polyoxyethylene surfactants containing carbonate linkages as biodegradable and chemically recyclable segments was designed and synthesized by a green process. A two-step carbonate exchange reaction was used: dimethyl or diphenyl carbonate was reacted with 1-alkanol, and the product was reacted with poly (ethylene) glycol in the presence of a lipase or chemical catalyst. The obtained carbonate-type nonionics exhibited good surface-active properties such as a low critical micelle concentration value and a surface tension lowering action. They were readily biodegraded by activated sludge, furthermore, could be chemical recycled using a lipase.