| abstract |
PROBLEM TO BE SOLVED: To provide a composite semipermeable membrane having significantly higher durability than conventional ones. The present invention provides a support membrane including a substrate and a porous support, and a support membrane provided on the porous support. And a thermoplastic resin, the weight average molecular weight (Mw) of the thermoplastic resin is 140,000 or less, 10 mm / min under a temperature condition of 25 ℃, Provided is a composite semipermeable membrane having a peel strength of 3.0 N/25 mm or more, which is measured by peeling the porous support from the substrate at a peeling direction of 180°. [Selection diagram] Figure 1 |