Preparation and characterization of wood polyalcohol-based isocyanate adhesives
Article first published online: 29 JUL 2005
Copyright © 2005 Wiley Periodicals, Inc.
Journal of Applied Polymer Science
Volume 98, Issue 2, pages 791–795, 15 October 2005
How to Cite
Tohmura, S.-I., Li, G.-Y. and Qin, T.-F. (2005), Preparation and characterization of wood polyalcohol-based isocyanate adhesives. J. Appl. Polym. Sci., 98: 791–795. doi: 10.1002/app.22072
- Issue published online: 29 JUL 2005
- Article first published online: 29 JUL 2005
- Manuscript Accepted: 6 FEB 2005
- Manuscript Received: 10 SEP 2004
- Japan International Cooperation Agency (through a research project on timber from manmade forests in the People's Republic of China).
Sugi (Criptmeria Japonica) wood meal was liquefied at 150°C with a mixture of poly(ethylene glycol) 400 and glycerin in the presence of a sulfuric acid catalyst. The resulting liquefaction products were used directly to prepare isocyanate adhesives via mixing with polymeric diphenylmethane diisocyanate without the removal of the residue. The properties of the liquefaction products and the performances of bonded plywood were tested. The results showed that the residue content decreased and the hydroxyl value increased as the reaction time increased. The viscosity and weight-average molecular weight significantly changed with the reaction time. All the dry test results of the shear strength met the Japanese Agricultural Standard (JAS) criteria for plywood. After a cyclic steaming treatment, however, only the plywood bonding with adhesives from the liquefied wood with a reaction time of 1.5 h satisfied the JAS criteria. The wood failure was very low. The emissions of formaldehyde and acetaldehyde were extremely low. Liquefied-wood-based isocyanate adhesives have the potential to become ideal wood adhesives because of their bond durability, safety, and recyclability.