| 摘要 |
(1) Provided is a vinyl alcohol-based graft copolymer that contains a structural unit represented by general formula (I) and a vinyl alcohol-based structural unit, has a vinyl alcohol-based polymer containing a pendant mercapto group as the main chain, has a polymerizable unsaturated monomer grafted from this mercapto group, and has a controlled base point of graft polymerization. (In the formula, R1 is a hydrogen atom or a carboxyl group, R2 is a hydrogen atom, methyl group, carboxyl group, or carboxymethyl group, and X is a C1-C22 divalent group containing a carbon atom and a hydrogen atom and optionally containing a nitrogen atom and/or an oxygen atom.) (2) Provided is an ion-exchange membrane having suppressed swelling in water and excellent flex resistance, provided with a vinyl alcohol-based graft copolymer having the above-mentioned vinyl alcohol-based polymer containing a pendant mercapto group as a stem and having an ionic polymer chain grafted from the mercapto group. |
