Multifunctional azo initiators for free radical polymerizations: uses thereof
US8097687B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 2009 |
| Grant date | Jan 17, 2012 |
| Priority date | — |
| Expiry date | Feb 25, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K5/235
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention provides compositions of matter, methods of their synthesis, and methods of their use in polymerization reactions. The compositions include polyfunctional initiators used to make star polymers when polymerized with monomers. The polyfunctional initiators are synthesized out of a multifunctional core with at least two functional groups and two or more initiator units bonded to the functional groups. The initiator units have two electron-withdrawing groups bonded to a central carbon atom and an azo group between the central carbon atom and the functional group. The polyfunctional initiators are particularly effective because when they decompose to form the radical core of a star polymer, the electron-withdrawing groups prevent the corresponding radical from forming any linear polymer contamination and only desired star polymers result. In addition when the desired star polymers are fed into a reaction vessel by streams with two different concentrations the star polymers produce superior properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.