Method of making block copolymers by solid state polymerization
US6960641B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2003 |
| Grant date | Nov 1, 2005 |
| Priority date | — |
| Expiry date | Dec 22, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/80
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of preparing block copolymers by solid state polymerization is described. A mixture of a partially crystalline polycarbonate having activated terminal aryloxy groups, for example terminal methyl salicyl groups, when heated together with an oligomeric polyester having reactive terminal hydroxy groups under solid state polymerization conditions affords block copolymers. The activated terminal aryloxy groups play a key role in preserving the block lengths of the starting materials. A control sample in which the partially crystalline polycarbonate lacks activated terminal aryloxy groups, for example polycarbonates substituted by phenol, affords a much lower molecular weight, more highly randomized copolymer product. The product block copolymers are useful as “weatherable” plastic materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.