Salinity tolerant water swelling material

摘要

PURPOSE:To provide a salt-resistant water-swelling material having a large swelling degree even in contact with an aqueous solution containing a salt and suitable for sealing a gap between segments for tunnel construction by dispersing a water-absorbing resin in a matrix, the water-absorbing resin being prepared from a specific sulfonic acid-containing unsaturated monomer as an essential component. CONSTITUTION:(A) A water-absorbing resin prepared by polymerizing monomer components consisting essentially of a sulfonic acid group-containing unsaturated monomer of the formula (R1 is H or methyl; R2 is 1-5C alkylene; X is H, alkali metal, etc.) in the presence of a crosslinking agent [e.g. ethylene glycol di(meth) acrylate] is dispersed in (B) a matrix comprising a thermoplastic resin and/or a rubber in an A/B ratio of 5-300 pts.wt./100 pts.wt.