Studies on developments of novel wooden resinified materials and wood-synthetic polymer composites

点击翻译按钮获取中文摘要

As a first topic, dissolution or liquefaction of chemically modified woods and their conversion to adhesives have been studied based on the original proposal. In order to achieve high waterproof gluability of wood phenol adhesives, avandant information could be obtained on phenolation of lignin during the liquefaction and resinification, the amount of formaldehyde and crosslinking agents added. The importance in lignin phenolation was proved by studies on phenol resinified adhesives from thiolignin. On the other hand, during this study, it has been found that non-chemically modified wood could also be liquefied with reactive organic solvents and that these solution obtained could easily converted to abhesives which have high functionality in gluing. Accordingly, following investigations have focussed on adhesives from non-treated wood. As a result, wood-phenol resin and wood-epoxy resin adhesives with waterproof gluability could be developed without chemical modification of wood. One o … More f the characteristics of the former resins is that they can be cured with high waterproof gluability at the temperature as low as amino-resins can be cured. A success in lowering the cure-temperature of resol-type phenol resin adhesives can contribute to the modelation of water content regulation of the wood veneer.Studies of wood-synthetic polymer composites have been made on two topics; one being on composites comprising chemically modified wood with thermoplasticity and thermofluidity and synthetic polymers, while the other being on composites of non-treated wood fibers or wood flours with synthetic polymers. The former composites were found to contain a high proportion of chemically modified wood and to be blended with ease with synthetic polymers because of the high thermal fluidity. The latter composites are characteristic of high strength properties due to the wood fiber or wood flour structure blended. In both cases, it became apparent that the composites with superior physical properties can be achieved by improving the gluability in its interface between synthetic polymers and wood itself. Particularly, an addition of the compatibilizer in a small amount was found to be effective in betterment of the properties of the composites. Less