COMPOSITE SEMIPERMEABLE MEMBRANE, SPIRAL TYPE SEPARATION MEMBRANE ELEMENT, AND METHOD FOR PRODUCING THEM

摘要

PROBLEM TO BE SOLVED: To provide a composite semipermeable membrane which is less likely to lower water permeability even when exposed to high temperature environment for a long period of time; a spiral type separation membrane element using the composite semipermeable membrane; a method for producing them; and a method for evaluating water-permeable performance of a composite semipermeable membrane which evaluates whether or not water permeability of the composite semipermeable membrane is easy to lower by heat with a simple evaluation method.SOLUTION: A composite semipermeable membrane has a skin layer containing a polyamide resin on a porous support. The skin layer has modulus of elasticity calculated by force curve measurement by AFM in water of 100 MPa or more.SELECTED DRAWING: Figure 1