Process for preparing aromatic polyester-polystyrene block copolymers
US5314954A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 23, 1992 |
| Grant date | May 24, 1994 |
| Priority date | — |
| Expiry date | Dec 23, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2810/40
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process is disclosed for preparing of aromatic polyester-polystyrene block copolymers which comprises subjecting preferentially styrene polymers (A) having terminal functional groups reactive with acid chloride groups and an excess of aromatic dicarboxylic acid dihalides (C) to condensation and then subjecting continuously the resultant mixture and aromatic dihydroxy compounds (B) to interfacial polymerization at the ratio (A)/[(B)+(C)] by weight of 5/95 to 80/20, without separating reaction products of styrene polymers (A) and aromatic dicarboxylic acid dihalides (C), and the block copolymers thus prepared contain a small amount of uncopolymerized styrene polymers, have long aromatic polyester segments, show low birefringence, good transparency, exceptionally low birefringence, low melt viscosity, and good mechanical strength, and are particularly useful as materials for optical instruments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.