Process for preparing polytrimethylene terephthalate
US6297315A · kind A · utility
14Cited by
6References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 11, 1999 |
| Grant date | Oct 2, 2001 |
| 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 (or alkyl ester thereof) is crystallized by immersion in water at a temperature within the range of 60 to about 100.degree. C. Hot-water treatment increases the crystallinity of the polymer to at least about 35% and increases pellet density to about 1.33 g/cm.sup.3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.