Claisen-type degradation mechanism of cellulose triacetate membranes in ethanol–water mixtures

This work reports for the first time the degradation mechanism of cellulose triacetate membranes exposed to ethanol–water mixtures. The process of membrane degradation is elucidated by XPS, ATR-FTIR, NMR to proceed via a classical Claisen-type condensation followed by water condensation reactions leading to the formation of the acetoacetate and ether pendant groups in the polymeric matrix. This work provides vital insight into the chemical stability and durability of the cellulose ester-based membranes for long term operation in liquid separation applications involving ethanol solutions.