Formaldehyde free microspheres and encapsulation
US11560447B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 2018 |
| Grant date | Jan 24, 2023 |
| Priority date | — |
| Expiry date | Apr 24, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F220/1818
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Processes for producing polymer microcapsules using vicinal functional oligomers are also described. The vicinal functional oligomers can be made by polymerizing an acrylate monomer, a styrene monomer, or both in the presence of a chain transfer agent. The vicinal functional oligomers can be reacted with epichlorohydrin to form vicinal epoxies. The vicinal epoxies can be reacted with polyamines to form epoxy polymer microspheres. The vicinal epoxies can be reacted with carbon dioxide in the presence of a catalyst to form vicinal cyclic carbonates. The vicinal cyclic carbonates can be reacted with polyamines to form isocyanate-free polymer microspheres. Polymer microspheres made by the processes are also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.