Solution of polymeric material.

摘要

A polymer solution contains a sulphonated polyarylethersulphone in a solvent mixture containing at least two components, one of which is a hydroxy group containing compound selected from water, an alkanol or a glycol and the other of which is a ketone. The solvent mixture typically has a delta-H in the range from 3 to 8.5; a delta-P in the range from 4 to 8 and a delta-D in the range 7.2 to 9.5. Each component of the solvent mixture is a liquid or low melting solid which is a non-solvent or poor solvent for the sulphonated polyarylethersulphone. Solvent mixtures which may be used include water and methyl ethyl ketone; water and acetone and ethylene glycol and acetone. The solutions can be used to produce an asymmetric membrane.