Methods and apparatus for the production of amorphous polymer suspensions
US6228934A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1999 |
| Grant date | May 8, 2001 |
| Priority date | — |
| Expiry date | Jun 9, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2367/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Methods and apparati have been developed for producing a suspension of predominately amorphous polymer particles, wherein the method includes thermally treating a suspension that includes crystalline or semi-crystalline polymer particles. The thermal treatment includes (a) heating a suspension of polymer particles of an appropriate size to a temperature effective to cause the polymer to become amorphous, and then (b) cooling the suspension of amorphous polymer particles below the melting point of the polymer at a rate effective to prevent substantial coalescence of the polymer particles. The method and apparati are effective for use with a variety of polymers having suitable crystallization parameters, although polyhydroxyalkanoate (PHA) polymers are preferred, particularly in an aqueous suspension medium. For PHA polymers, the polymer particles subjected to treatment preferably are of a size of less than 5 .mu.m, or more preferably less than 1.5 .mu.m in diameter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.