WATER-SWELLABLE COMPOSITION FOR WATER-LEAKAGE PREVENTION

摘要

- 20 -ABSTRACT OF THE DISCLOSUREThe water-swellable composition for water-leakageprevention useful in construction works is a compoundedmaterial comprising (A) 100 parts by weight of an elastomersuch as a polychloroprene rubber and (B) 20 to 300 partsby weight of a highly water-absorptive resin which is acrosslinked material of a copolymer of a ternary monomericmixture composed of (meth)acrylic acid, a compound of theformulaCH2=CR-CO-O-?-CH2-?-?SO3X,R being H or methyl, X being H or a monovalent cation and nbeing an integer of at least 2, such as sodium 2-sulfoethylacrylate, and (meth)acrylamide in a specified proportion.The crosslinks are formed either by reacting the copolymerwith a crosslinking agent such as propylene glycol or bycopolymerizing the monomers in the presence of a copolymer-izable crosslinking agent such as N,N-methylene bisacryl-amide. The composition is capable of exhibiting stableswelling pressure and strength even in water containingpolyvalent metal ions, e.g., calcium ions.