Purified polymer and methods for making
US11866541B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2021 |
| Grant date | Jan 9, 2024 |
| Priority date | — |
| Expiry date | Apr 17, 2042 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/54
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method to purify a polymer is disclosed. The method is part of a manufacturing process wherein a virgin polymer is produced from a polymerization process employing at least a monomer or a comonomer as a feedstock. The monomer or the comonomer is selected from the group consisting of organic polar monomers, inorganic monomers, vinyl aromatic monomers, conjugated dienes, and mixtures thereof. In the method, the polymer in solid, liquid or molten state is brought into contact with a fluid solvent or an extraction fluid in a supercritical state or near supercritical state. The contact is at controlled temperature and pressure, allowing the fluid solvent to diffuse into the polymer and extract the impurities intended to remove. The method can be used to remove at least 10%, or at least 20%, or at least 50% of the target impurity from the polymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.