【摘要】 我们在研究落叶松树皮化学的基础上。根据它含有较高的多酚类和黄酮类化合物的特点应用其与甲醛反应的聚合性能,试验作为木工胶粘剂以供生产上的需要。这项研究以兴安落叶松树皮为主要原料,通过浸提、制胶、压板和质量测验等连续性的反复室内试验,先从刨花板开始验证其利用价值取得预期结果。采用稀碱直接处理树皮方法所浸提出干物质的得率按干树皮计可达30％,其中有用的反应物质达78％左右。浸提物可制备成浓缩液态或制成干粉更便于装运保存并易于热溶,质量不变。压板配胶主要用树皮胶粉及少量多聚甲醛,除石蜡外不加其它任何胶类或增强剂,施胶可用热溶约60℃胶水喷洒或将于胶粉洒匀,按一般三段加压,分别用140℃及170℃热压,制成1厘米及2厘米厚度的中密度刨花板,产品各项质量可达国家规定的一级品标准。综合分析衡量各方有关问题,认为落叶松树皮胶的一些优点是:一、资源丰富,得率较高;二、质量良好,成本较低;三、工艺简单,易于推广。此外,综合了国内外这类工作进展概况,展望未来,认为这类胶是有发展前途的。进一步研究使其能代替酚醛胶类,这对节约能源是有利的。即便作为一般木工胶以缓和胶源紧张也不应视为权宜之计。将来深入研究树皮多酚类和黄酮类化合物的基础理论并扩大树种和用途,可为充分合理利用更多还原

【Abstract】 Extracts from bark of Larix gmelini (Rupr.) Rupr. was studied to examine its potential value as bonding agent for particleboard without adding any synthetic resin. Starting from the extraction of raw material till the qualification tests of final products, some encouraging repeated results through the whole process were obtained. Extraction by 3 % sodium carbonate and sulfited was suitable. The yield could reach 30% based on oven-dried bark and its reactive phenolics up to 78%. Extracts were prepared both in desired concentrated liquid form and in dried powder. The powder was preferable due to the convenience for handling and kept for a year in room temperature without changing its effectual properties. Mixed planer shavings from ash and bass wood were first sprayed by concentrated extracts or by dissolved powder extracts which was easily soluable in hot water at about 60℃. Then, small amount of fine powdered paraformaldehyde was added to the shavings and the whole mass was well mixed for pre-pressing board. Schedule of hot press at 140℃ and 170℃ both under three-steps pressure was applied respectively. Types of particleboard of 1 cm. and 2 cm. in thickness were made and their density ranging from 0.67 to 0.80 g/cubic cm. which were mostly in the category of medium-density. Qualification tests such as modulus of rupture, tensile strength and thickness swelling were all met specification of our national standard. The progress in this field was reviewed and other related problems were discussed. This study proved that it is feasiable to use larch bark extracts as adhesive for particleboard with many advantages. To broaden the usage of this extracts and more barks from different tree species should be studied.更多还原