Polypiperazinamide-based reverse-osmosis membranes and post-treatment process for their preparation

摘要

The process comprises a chemical-physical post-treatment which allows to obtain reverse-osmosis membranes with high flow, high rejection and high stability. The post-treatment is performed after the following steps: a) preparation of a polypiperazinamide solution in an original polar solvent; b) application of the solution on a support or drawing in the form of a hollow fiber; c) partial evaporation of the original solvent; d) gelling by phase reversal by passage through a coagulation bath.