Method for solid phase polymerization
US5955569A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1996 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Nov 27, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/584
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An improved method for increasing the relative viscosity and molecular weight of a polyamide polymer (such as nylon 6,6, nylon 6, and the like) while in the solid state involving the use of a phosphorus-containing catalyst (such as 2(2'-pyridyl) ethyl phosphonic acid or the like) in combination with an oxygen free gas characterized by a low dew point (typically below 30.degree. C. and preferably below -30.degree. C.). The combination of affording commercial operation at greater through put at lower temperature. Such a process is of particular value during the production of terpolyamide and multipolyamide polymer intended for use in colored nylon fiber manufacture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.