Polymeroploesning and procedure for the preparation of semipermeable membranes using polymeroploesningen

摘要

Solutions of sulphonated polyaryletherketones in a solvent mixture of at least three liquids or low melting solids which are non-solvents or poor solvents for the polymer, can be used to produce asymmetric semi-permeable membranes. The polymer may be a polymer of (Ph1-O-Ph2-O-Ph1-CO) and optionally (Ph1-O-Ph1-CO) and (Ph1-O-Ph1-O-Ph1-CO) wherein Ph1 and Ph2 are respectively unsulphonated and sulphonated phenylene residues. The components of the solvent mixture have specified solubility parameters. A suitable solvent mixture is one formed from water, 1,4-dioxane and acetonitrile.