Amphipathic polymers with stimuli-responsive microdomains for water remediation: Binding studies with p-cresol

Amphipathic, stimuli-responsive water-soluble polymers have been investigat ed as potential remediation agents for micellar enhanced ultrafiltration (M EUF). The systems represent divergent architectural types, a triblock ABA c opolymer of PEO-PPO-PEO, an n-octylamide modified poly(sodium maleate-alt-e thyl vinyl ether), and the transport protein, bovine serum albumin. Each ty pe exhibits stimuli-dependent microphase separation or domain formation in response to temperature, pH, and/or ionic strength changes. Segmental assoc iations result in hydrophobic clusters resembling those present in small mo lecule surfactant micelles. The effects of such segmental aggregation on se questration of a model hydrophobic foulant, p-cresol, have been investigate d using equilibrium dialysis. The favorable molar binding values, the large hydrodynamic dimensions of the stable polymer aggregates, and potential re versibility of foulant loading could have commercial utility in high flow r ate, multiple-pass remediation processes. (C) 1999 John Wiley & Sons, Inc.