Preparation and characterization of ultrathin, gas selective membranes based on layer-by-layer self-assembly technique

Abstract

Alternating electrostatic deposition of cationic and anionic polymer that yields ultrathin, gas selective polyimide membranes on porous alumina supports was investigated in this project. Polyimide membrane was prepared onto porous alumina substrate and was studied as a flat, supported membrane. The gas permeability rates were varied and the effects of concentration of positively and negatively polymeric solution, type of polyelectrolytes, pores size of porous alumina membrane, size of gases permeate through membrane and number of bi-layers of oppositely charged membrane on the performance of the final polymeric membrane were studied. Pure gas permeation tests were carried out on these ultrathin multi-layered membranes and the results were analyzed.