Molecular Selective Cross-Linked Amphiphilic Micelles Network: Antibiofouling Property and Fractionation of Dye and Salt

Molecular selective membranes having high organics rejection and extremely low salt rejection are potential candidates for fractionation and resource recovery. The added antibiofouling/antifouling property is advantageous in view of smooth fractionation. Herein, we report the construction of a core cross-linked micelles network of partially alkylated (C12) poly(vinyl imidazole) on the base membrane substrate to obtain a sub-ultrafiltration ranged barrier. Self-assembly of the cross-linked micelles on the base substrate is facilitated by the hydrophobic interaction among the alkyl chains and further intermicelles cross-linking, which leads to the close micelle array and subsequent formation of a stable cross-linked micelle network. The spaces among the micelles in the network preferentially allow water and salt to permeate through, while bigger molecules are intercepted. The cross-linked micelle network-based membrane (TUF-3) prepared by the cross-linked micelles (0.2% w/v) shows >99.5% Congo red and Direct red-80 (1 g L^-1) rejection in the presence or the absence of salts with a salt to dye selectivity of 240-498 and a pure water permeance of 30 L m^-2 h^-1 bar^-1. The TUF-3 membrane exhibits low dye fouling propensity, antimicrobial activity (98.5 to >99% bacterial reduction), and inhibition of biofilm formation. The amphiphilic cross-linked micelles network with an added functional motif shows promise for the fractionation and resource recovery operations.