Method for preparing novel waterborne polyurethane foam layer for synthetic leather
US11692307B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2021 |
| Grant date | Jul 4, 2023 |
| Priority date | — |
| Expiry date | Feb 18, 2042 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06N2211/28
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for preparing a novel waterborne polyurethane foam layer for synthetic leather is disclosed. The method includes first preparing a charged cellulose nanofiber by using a wood pulp as a raw material; meanwhile, subjecting a polyisocyanate, a macromolecular diol, a hydrophilic chain extender and a small molecular chain extender to a polyaddition reaction and an acid-base neutralization reaction in sequence, to obtain a cationic or anionic waterborne polyurethane; adding the charged cellulose nanofiber and a certain amount of a crosslinking agent to the oppositely charged ionic waterborne polyurethane emulsion, stirring the resulting mixture, forming a bimolecular layer at the gas/liquid interface by a self-assembly of the cellulose nanofiber and waterborne polyurethane nanoparticles through electrostatic interactions to obtain a stable Pickering foam; using the stable Pickering foam as a template, drying and solidifying to obtain the waterborne polyurethane foam layer for synthetic leather.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.