Process for preparing porous and water-absorbent resin
AssigneeNippon Gohsei Kagaku Kogyo Kabushiki Kaisha
InventorsHiroshi Aoyama, Tetsuo Moriya, Susumu Kondo
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Abstract
A process for preparing a porous and water-absorbent resin which includes dispersing an aqueous solution containing at least one .alpha.,.beta.-unsaturated carboxylic acid monomer, its alkali metal salt or its ammonium salt in a hydrophobic organic solvent, and conducting a reversed phase suspension polymerization by using a water-soluble radical polymerization initiator, while distilling away the hydrophobic organic solvent together with water. A porous and water-absorbent resin having excellent absorbency and a remarkably improved rate of water absorption can be easily and efficiently obtained on an industrial scale.
Claims7
A process for preparing a porous and water-absorbent resin which comprises:
- dispersing an aqueous solution containing at least one of an .alpha.,.beta.-unsaturated carboxylic acid monomer, its alkali metal salt and its ammonium salt in a hydrophobic organic solvent in the presence of a dispersing agent, and
- conducting a reversed phase suspension polymerization by using a water-soluble radical polymerization initiator, while distilling away the hydrophobic organic solvent together with water to dehydrate, wherein the distillation is begun during continuous or intermittent addition of said aqueous solution to said solvent and wherein said distillation is continued during said polymerization.
Dependencies are inferred from the claim text.