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

作为第一个主题，化学改性木材的溶解或液化及其转化为粘合剂的研究已在原建议的基础上进行。为了使木酚胶粘剂具有较高的防水胶粘性，可以对木质素在液化和树脂化过程中的酚醛化、甲醛的添加量和交联剂的添加量进行研究。巯基木质素酚醛化胶粘剂的研究证实了巯基木质素酚醛化的重要性。另一方面，在本研究中发现，未经化学改性的木材也可以用活性有机溶剂液化，这些溶液可以很容易地转化为具有高粘合功能的胶粘剂。因此，接下来的调查主要集中在未处理木材的粘合剂上。结果表明，无需对木材进行化学改性，即可研制出具有防水胶粘性的木酚树脂和木环氧树脂胶粘剂。前一种树脂的另一个特点是，它们可以在与氨基树脂一样低的温度下固化，具有很高的防水胶合性。降低溶解型酚醛树脂胶粘剂固化温度的成功，有助于模拟木饰面含水率的调节。木材合成聚合物复合材料的研究主要集中在两个方面；一种是由具有热塑性和热流动性的化学改性木材和合成聚合物组成的复合材料，而另一种是由未经处理的木纤维或木粉与合成聚合物组成的复合材料。研究发现，前一种复合材料含有高比例的化学改性木材，由于热流动性高，与合成聚合物容易混合。后一种复合材料由于混合了木纤维或木粉结构，具有较高的强度性能。在这两种情况下，很明显，通过改善合成聚合物和木材本身之间界面的胶合性，可以获得具有优越物理性能的复合材料。特别是，少量添加相容剂可以有效地改善复合材料的性能。少

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