Process for increasing the molecular weight of polyamides and other condensation polymers
US5543495A · kind A · utility
19Cited by
13References
41Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1994 |
| Grant date | Aug 6, 1996 |
| Priority date | — |
| Expiry date | Mar 8, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G69/28
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention concerns a process for increasing the molecular weight and viscosity of polyamides and other condensation polymers, by first injecting an inert gas into the polymer melt at elevated pressure, then stripping the volatiles from the polymer through the application of reduced pressure, followed by holding the polymer at elevated temperatures long enough for the reaction to occur. Activators may be added to the polymer. Port areas used in the stripping zone, may be kept hot for continuous operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.