Patent · US Expired

Highly water-absorptive polymer and process for producing the same

US5998553A · kind A · utility

5Cited by
0References
4Claims
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Assignee

Inventors

Key dates

Filing dateApr 22, 1998
Grant dateDec 7, 1999
Priority date
Expiry dateApr 22, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F2/32
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for producing a highly water-absorptive polymer, which comprises suspending an aqueous solution containing a water-soluble polymerizable monomer and an optional crosslinking agent into droplets in a hydrophobic organic solvent in the presence of a dispersant and a water-soluble radical polymerization initiator, and allowing the water-soluble polymerizable monomer to polymerize in the droplets, wherein the dispersant is a phosphoric ester surface active agent represented by the following general formula [I]: ##STR1## wherein R.sup.1 represents an alkyl or alkylaryl group having 8 to 30 carbon atoms, R.sup.2 represents OH group or a group of the formula --(CH.sub.2 CH.sub.2 O).sub.m --OR.sup.1, and m and n are an integer of 1 to 30, and the aqueous solution is successively fed to the hydrophobic organic solvent so that the droplets of different polymerization degrees can be present in the solvent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.