木材液相乙酰化及抗收缩效果的研究

Study on Liquor Phase Acetylation of Wood and Its Antishrink Efficiency

本文研究了三种木材液相乙酰化的影响因素以及乙酰化木材的抗收缩效果。用乙酸酐作为乙酰剂和以二甲苯作为溶剂,处理材的增重与反应温度和时间存在着线性关系。反应的最佳温度为120℃,时间为7～11h,乙酸酐和二甲苯的容量比为1:1。乙酰化显著地提高了木材的尺寸稳定性。抗收缩率与处理材的增重成正比。当处理材的增重大于15％时可取得满意的抗收缩效果,抗收缩率达到60％以上。乙酰化木材经过了三次干燥—浸水循环试验,其结果表明乙酰化所取得的抗收缩效果有很强的抗流失性。本研究证实:乙酰化是提高木材尺寸稳定性的有效措施,对提高材质有重要意义。

This paper deals with some major factors effecting liquor phase acetylation of wood from three species. Linear correlations between the weight percent gain (WPG) and the reaction temperature, and time were found when acetic anhydride and xylene were used as treating chemicals. The optimum reaction temperature was 120°C, and the reaction time was 7 to 11 hours and the volume ratio of anhydride to xylene 1:1. The dimensional stability of wood obviously was improved by acetyla- tion. Antishrink efficiency (ASE) was directly proportional to WPG. An expectant result of dimensional stabilization was obtained and ASE reached more than 60 percent for acetylated wood with more than 15 WPG. Three drying and water soaking cycle tests revealed that the treated wood has a strong resistance to leaching by water. The effectiveness of acety-lation to enhance some wood properties has been further confirmed by the present experments.