Superabsorbent acrylic powders
US5397845A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 1993 |
| Grant date | Mar 14, 1995 |
| Priority date | — |
| Expiry date | Aug 12, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61L15/60
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Particulates of a superabsorbent partially, neutralized acrylic polymer, e.g., polyacrylic acid, having a mean particle size ranging from 100 to 500 .mu.m, essentially monodisperse and essentially devoid of fines having a particle size of less than 100 .mu.m, having a nonuniformly surfaced spheroidal particle morphology and well suited for a variety of hygienic applications, are prepared by (i) polymerizing a suspension of an acrylic monomer charge I in an organic medium and producing a suspension of acrylic polymer gel particles, such acrylic monomer charge I having a degree of neutralization greater than that desired in the final superabsorbent polymer, (ii) next absorbing a second acrylic monomer charge II into the gel particles, such acrylic monomer charge II having a degree of neutralization less than that desired in the final superabsorbent polymer, and (iii) polymerizing in the gel particles the second acrylic monomer charge II.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.