Thin-film composite poly(esteramide)-based membranes

The permeation and chlorine tolerance of various thin-film composite poly(e steramide) membranes were investigated. The membranes were synthesized inte rfacially by reacting trimesoyl chloride with an aqueous phase containing m -phenylene diamine plus either m-aminophenol (m-AP), bisphenol-A. (Bis-A) o r hydroquinone (HQ). The amount of eater groups actually incorporated in th e membranes at various starting stoichiometric ratios was quantified. Membr anes incorporating Bis-A or HQ gave complete sucrose rejection while the sa lt rejections decreased in the order: HQ > m-AP > Bis-A based systems. The HQ:m-PDA system showed permeation characteristics approaching those of poly amide membranes synthesized from m-PDA alone. The membrane chlorine toleran ce was significantly increased by the incorporation of ester linkages.