| 摘要 |
PURPOSE:To obtain the title highly expandable water-absorptive polymer having excellent air permeability by cross-linking the polymer of an alkali acrylate obtained by suspension polymerization in the presence of an inorg. substance such as montmorillonite in azeotropic dehydration, and eliminating the stickiness of the gel formed by water absorption. CONSTITUTION:An aq. soln. contg. the alkali acrylate is dispersed and suspended in an aliphatic hydrocaron solvent, and polymerization is carried out. Natural or synthetic stratified clay minerals such as montmorillonite or its product treated with acid having cation exchange capacity is added by 0.5-30wt%, based on the monomer, a cross-linking agent such as ethylene glycol diglycidyl ether is added to the extent of0.05-2wt%, based on the monomer, then azeotropic dehydration is carried out, and the material is dried. The granular polymer particles are highly expandable, and appropriately used in the water retaining material for agricultural and gardening soil, medical supplies, etc.
|
