New Coating Techniques for Composite Membranes. Phase 1

摘要

Researchers have developed a method for producing thin, defect-free, compositemembranes based on the use of incipiently gelling polymer solutions. The key factor in the coating process is the polymer-solvent interaction. When the solvent chosen is one in which the polymer has very limited solubility, very thin, defect-free coatings can be produced. Solutions based on good solvents require higher polymer loadings to form defect-free coatings and therefore produce thicker permselective layers. A qualitative model is proposed for the formation of defect-free coatings on porous substrates. Experimental data from polyether-amide block copolymer coatings on polysulfone support membranes confirm the predictions of the model.