Permeable superabsorbent and process for production thereof
US12403448B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 14, 2020 |
| Grant date | Sep 2, 2025 |
| Priority date | — |
| Expiry date | Jan 13, 2043 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L33/02
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A highly permeable superabsorbent is prepared by a process comprising polymerizing an aqueous monomer solution comprising a) at least one ethylenically unsaturated monomer which bears acid groups and is optionally at least partly in salt form, b) at least one crosslinker, c) at least one initiator, d) optionally one or more ethylenically unsaturated monomers copolymerizable with the monomers mentioned under a), and e) optionally one or more water-soluble polymers; drying the resulting polymer, optionally grinding the dried polymer and sieving the ground polymer, optionally surface postcrosslinking the dried and optionally ground and sieved polymer, adding x-ray-amorphous aluminum hydroxide powder after drying, grinding or sieving, and, if surface postcrosslinking is conducted, during or after this surface postcrosslinking, adding 0.1% to 10% by weight, based on the amount of polymer prior to the addition of the x-ray-amorphous aluminum hydroxide powder, of water after the addition of x-ray-amorphous aluminum hydroxide powder, wherein the water is added to the superabsorbent in at least three portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.