Organosolv lignin-modified phenolic resins and method for their preparation
US5010156A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1990 |
| Grant date | Apr 23, 1991 |
| Priority date | — |
| Expiry date | Mar 12, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L97/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A lignin-modified phenol-formaldehyde resin for use as an adhesive for particulate wood products is disclosed which is prepared by reacting phenol and formaldehyde with an aqueous alkaline solution of an organosolv lignin. The organosolv lignin used in the formation of the resin is obtained from a pulping liquor prepared from particulate wood material from hardwood trees, aqueous polar organic solvent, and an acid catalyst. The resin allows for replacement of phenol or organosolv lignin at a level of up to 40% without detrimentally affecting its performance in terms of bonding strength or durability. The resin of the present invention is also superior to prior art lignin-modified resins in that it is low in sulfate, ash and sulfur residues, and thus will not give off distracting or harmful sulfur odors during resin preparation or hot-pressing of the adhesive and is unaffected and not solubilized by water.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.