WATER SWELLABLE WATER CUT-OFF MATERIAL

摘要

PURPOSE:To obtain a water swellable water cut-off material useful for preventing leakage of water at A concrete joint part, having excellent safety to environment and execution, by using a water swellable substance comprising a specific hydrophilic cross-linked polymer. CONSTITUTION:This water swellable water cut-off material is obtained by using a hydrophilic cross-linked polymer prepared by treating an acrylonitrile- based polymer swellable by water absorption with a highly concentrated aqueous solution of an alkali metal hydroxide. The water cut-off material preferably has 20-98% void ratio and 30-350 times swelling ratio.