Apparatus for crystallization of polytrimethylene terephthalate
US6461575B1 · kind B1 · utility
12Cited by
5References
1Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 11, 1999 |
| Grant date | Oct 8, 2002 |
| Priority date | — |
| Expiry date | May 11, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0041
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The pelletized product of melt condensation polymerization of 1,3-propanediol and terephthalic acid is crystallized in a vessel designed for continuous fluidized bed flow of the pellets in water at a temperature within the range of about 65 to about 100° C. Hot-water treatment in the vessel permits crystallization of the pellets in a continuous operation and results in an increase of the crystallinity of the polymer to greater than about 35% and an increase in pellet density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.