PURPOSE: To obtain a semipermeable membrane comprising a polymer compsn. excellent in contamination resistance obtd. by mixing a contamination-resistant polymers comprising a hydrophilic component and a hydrophobic component, by specifying the difference between the max. and the min. proprotions of the hydrophilic component in the semipermeable memberane.
CONSTITUTION: This semipermeable membrane contains a compsn. prepared by mixing two or more kinds of contamination-resistant polymers comprising a hydrophilic component and hydrophobic component as the structural component. It is specified that the difference between the max. and the min. proportion of the hydrophobic component is ≥5wt.%. By this method, affinity between a polymer having high hydrophobic content and a noncontaminant material can be increased even when the average hydrophilic component is same, so that a stable molded body or a mixture soln. can be obtd. in a compatible or semicompatible state. Thereby, the obtd. membrane is excellent stability and contamination resistance.
MITSUNAGA MASAHIRO
TANAKA KAZUSANE
TERADA RYOZO
