Water-redispersible powders of film-forming polymers having a core/shell structure
US6224981A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1997 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | Dec 5, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to a water-redispersible powder based on film-forming polymers which are substantially water-insoluble and which are prepared by aqueous emulsion polymerization of monomers containing ethylenic unsaturation and with a "core/shell" structure comprising a hydrophobic core based on a polymer exhibiting a Tg (glass transition temperature) of between -30 and 25.degree. C., preferably between -10 and 20.degree. C., and a shell, the shell being bonded to the core by covalent bonds resulting from the reaction of an agent for grafting the shell onto the ethylenic unsaturations remaining in the core, characterized in that the shell is prepared by emulsion polymerization, on the core particles, of a mixture of monomers comprising at least one monomer chosen from styrene and a C.sub.1 -C.sub.12 alkyl acrylate or methacrylate, at least one monomer carrying a saccharide group and exhibiting at least one ethylenic unsaturation, and at least one grafting agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.