Process for solid phase polymerization of polyester
US4161578A · kind A · utility
69Cited by
1References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 12, 1978 |
| Grant date | Jul 17, 1979 |
| Priority date | — |
| Expiry date | May 12, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/80
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for the continuous production of high molecular weight polyethylene terephthalate wherein the granular polymer having an intrinsic viscosity of at least 0.4 is crystallized, dried and polymerized in the solid phase by polycondensation. Two methods of crystallization are described which aid the process in overcoming problems associated with sticking in the polymerization stage. The method is characterized by polycondensation at a temperature greater than the crystallization temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.