Solid-state polymerization of a liquid crystalline polymer
US8669341B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2012 |
| Grant date | Mar 11, 2014 |
| Priority date | — |
| Expiry date | Aug 27, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2019/0481
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method for forming a high molecular weight thermotropic liquid crystalline polymer is provided. The method includes melt polymerizing two or more monomers in the presence of a unique aromatic amide oligomer to form a prepolymer, and then solid-state polymerizing the prepolymer to achieve a target molecular weight. The present inventors have discovered that a unique aromatic amide oligomer can be employed to help increase the “low shear” complex viscosity of the resulting solid-state polymerized composition. This allows for the attainment of higher than conventional “low shear” complex viscosity values and/or a substantial reduction in the solid-state polymerization time needed to achieve a target complex viscosity. In addition, the oligomeric flow aid can also accelerate the extent to which the “high shear” melt viscosity is increased during solid-state polymerization, which may also contribute to a substantial reduction in the solid-state polymerization time needed to achieve a certain molecular weight.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.