Method for crystallizing a polyester comprising at least one 1,4:3,6-dianhydrohexitol unit
US12134680B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 2019 |
| Grant date | Nov 5, 2024 |
| Priority date | — |
| Expiry date | Nov 24, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/78
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A crystallization method that comprises a step of providing a polyester comprising at least one 1,4:3,6-dianhydrohexitol unit, and a step of crystallizing this semi-crystalline polyester at a pressure of at least 600 mbar absolute. The method according to the invention makes it possible to strongly limit, or even eliminate, the phenomenon of polyester expansion during crystallization. Advantageously, the elimination of the expansion phenomenon through pressure conditions implemented according to the invention thus makes it possible to dispense with obtaining very fragile empty spheres that break when agitated and thus cause the formation of undesirable fine particles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.