Self-expanding lignofoam compositions and lignofoams made therefrom
US11261308B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Apr 23, 2019 |
| Grant date | Mar 1, 2022 |
| Priority date | — |
| Expiry date | Dec 4, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2471/02
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Methods of making self-expended lignofoams are provided. In embodiments, such a method comprises exposing a self-expanding lignofoam composition comprising raw lignin and a thermoplastic polymer to an elevated temperature for a period of time to soften the composition, desorb water from the raw lignin or induce at least some hydroxyl groups of the raw lignin to undergo dehydration reactions to generate water or both, vaporize the water, and generate pores throughout the softened composition. The method further comprises cooling the porous, softened composition to room temperature to provide the self-expanded lignofoam. The self-expanding lignofoam composition is free of an added plasticizer, an added lubricant, an added foaming agent, and an added blowing agent, and the thermoplastic polymer is not a starch, not a polyurethane, and not a polysiloxane. The resulting self-expanded lignofoams are also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.