Liquid crystal polycondensates with improved heat stability, a process for their preparation and their use for the production of shaped articles, films, fibres and filaments
US5030703A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 1989 |
| Grant date | Jul 9, 1991 |
| Priority date | — |
| Expiry date | Sep 5, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K19/3809
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The liquid crystal polycondensates according to the invention based on aromatic hydroxycarboxylic acids, if appropriate aromatic aminocarboxylic acids, diphenols, if appropriate aminophenols, aromatic dicarboxylic acids and if appropriate carbonic acid which are obtainable by polycondensation of the difunctional monomers mentioned in the melt in the presence of aromatic esters with a defined sequence of the structural units of the formula ##STR1## of oligomers with random distribution of the structural units of the formula ##STR2## have a good heat stability and exhibit a stable viscosity under the processing conditions. The liquid crystal polycondensates can be used for the production of shaped articles, films, fibers and filaments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.