思茅松的苯酚液化及树脂化研究

研究了硫酸催化条件下,将恩茅松在苯酚中液化用于制备酚醛树脂的技术工艺,分析了各工艺参数对思茅松液化效率的影响,测定了由液化产物制备的液化木基酚醛树脂的物理化学性质和胶合强度。结论如下：1）．液比、反应温度、时间和木粉目数是影响液化反应效率的重要因素,液化产物的残渣率均随上述工艺参数值的升高而降低。2）．残渣含量对树脂物化性质和胶合强度均有影响,残渣含量降低,树脂粘度减小,聚合时间缩短,游离酚含量降低,胶合强度升高。3）．甲醛／苯酚摩尔比对树脂的物化性质和胶合强度也有影响,甲醛／苯酚摩尔比增加,树脂粘度增加,聚合时间减少,游离酚含量减低,胶合强度升高。

Study on liquefaction of pinus khasys wood by phenol and its resinification

The research focus on the liquefaction of pinus khasys wood by phenol in the presence of sulfuric acid used as a catalyst. The effects of phenol-to-wood ratio, reaction temperature, time and size of wood powder on the phenolation extents were determined. Adhesive resins were prepared from liquefied wood and the influence of residue contents of liquefied wood and different molar ratios of formaldehyde to phenol on physical and chemical characteristics of liquefied wood resins were investigated. Glue strength and wood faiIure were measured according to national standards. The results showed that 1）. Liquid ratio, reaction temperature, time, and size of wood powder all show great effect on the rate of liquefaction. The residue contents of liquefied wood decrease with increasing liquid ratio, reaction temperature, time and size of wood powder and become consistent when these parameters reach their reasonable level. 2）. Residue contents have great influence on physical and chemical characteristics and glue strength of liquefied wood resins. With the reducing of residue contents of liquefied products, the viscosities, solid contents and free phenol contents of liquefied wood resins all decrease, but their glue strength increase remarkably. 3）. Molar ratio of formaldehyde to phenol is also an important factor of physical and chemical characteristics and glue strength of liquefied wood resins. The higher molar ratio, the higher viscosities, the shorter curing time, the less free phenol contents and higher glue strength of liquefied wood resins.