Morphological control of porous membranes based on aromatic polyether/water soluble polymers

Abstract

This work describes the development of porous membranes based on blends of an aromatic polyether bearing main and side chain pyridine units (AP) with hydrophilic ionic polymers, like poly(sodium 4-styrenesulfonate) (PSSNa) and its acid form (PSSH), or non-ionic like polyvinylpyrrolidone and polyethylene glycol. Porous membranes were obtained after the removal of the water soluble polymers from the respective blend. The effect of various parameters such as water soluble polymer used (pore former), blend composition, casting solvent, and solvent evaporation level on porous structure formation was studied thoroughly. Specifically, SEM examination for the aforementioned systems indicated various porous morphologies depending on experimental conditions as well as thermodynamic and kinetic parameters occurring during their formation. The thermal properties of the membranes were influenced by the kind of the pore former, as revealed by thermogravimetric analysis. Special attention was paid to the systems AP/ PSSNa and AP/PSSH to evaluate their miscibility via dynamic mechanical analysis and ATR-FTIR spectroscopy. AP/PSSNa membranes have been preliminary used to test the water permeability for water purification. The tests revealed high water flux values at increased PSSNa concentrations.

Preparation of Porous Polymeric Membranes Based on a Pyridine Containing Aromatic Polyether Sulfone

“…Blending, as well as the phase inversion mechanism, play a crucial role in the final structure [32]. The effect of various parameters during the whole process interfere in the pore architectures; adjusting the membrane performance [33]. For this reason, the role of different parameters (initial and final total polymers’ concentration, PDSPP/SPDSPP composition, PDSPP molecular weight, type of solvent, time, temperature and composition of coagulation bath, type and concentration of porogen) on the porosity control of these new polysulfone-type aromatic polyethers-based membranes were investigated.…”