Stable free radical polymers
US6967228B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 2003 |
| Grant date | Nov 22, 2005 |
| Priority date | — |
| Expiry date | Aug 17, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L55/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A functional polymer having at least one substituent capable of forming a stable free radical is formed by polymerizing a diene monomer, such as butadiene, to form a first polymer block of the functional polymer. The first polymer block has a weight average molecular weight of less than 150,000. A vinyl aromatic monomer, such as styrene, is polymerized to form at least a second polymer block of the functional polymer. The copolymer is contacted with a stable free radical providing compound to form the functional polymer. By adding sufficient vinyl aromatic monomer, a low molecular weight functional rubber polymer can be rendered processable at ambient temperatures, while maintaining a solution viscosity which is suited to subsequent free radical catalyzation of vinyl aromatic monomers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.