Inducing surface porosity in aqueous-quenched, microporous Nylon 11 and Nylon 12 films

摘要

Nylon 11 and Nylon 12 have been studied for many years for the purpose of fabricating microporous films. Unfortunately, these polymers have somewhat unique properties that prevent the films from exhibiting porous surfaces when their solutions undergo thermally induced phase separation by quenching in water. Without surface pores, these films have limited utility as water purification membranes. In this work, application of high temperature diluent coatings to the surface prior to quenching is shown to enable the formation of surface porosity in Nylon 11 and Nylon 12 films. Furthermore, the pore sizes achieved are suitable for ultrafiltration applications. Following successful lab-scale coating experiments, the effects of coating thickness, temperature, and solvent type on surface morphology are demonstrated over five film extrusion trials. (C) 2017 Wiley Periodicals, Inc.