人造板用胶粘剂的发展趋势

2000年世界人造板的产量为1.54亿m3,耗用370万t胶粘剂。人造板工业使用的三大胶是脲醛树脂胶、酚醛树脂胶和三聚氰胺-甲醛树脂胶。脲醛树脂胶作为主要品种,用量超过250万t/a,降低树脂制备中甲醛/尿素的物料配比、添加甲醛捕集剂是减少甲醛释放量的有效方法,但需引入耐水性物质改善树脂的耐水性;以尿素代替部分三聚氰胺制备三聚氰胺-甲醛树脂,可降低树脂的成本,但要达到较好的耐老化性,三聚氰胺和尿素的比例应大于40:60;提高固化速度、降低固化温度是酚醛树脂的发展趋势,引入金属离子、提高碱性、提高聚合度和外加固化促进剂是主要途径。低毒、优质的木材胶粘剂将越来越受到关注。

Development Trend of Artificial Plate Adhesives

In 2000, the artificial Plate capacity is 154m cubic metres in the world, using 3.7m tons of adhe-sives. The three main adhesives for artificial plate are urea-formaldehyde resin adhesive, phenolic-formaldehyde resin adhesive and melamine-formaldehyde resin adhensive. The consumption of UF resin adhesive, a main variety, is over 2. 5 mt/a. In order to reduce formaldehyde release, lowering the ratio of F/U in manufacturing the resin and adding formaldehyde collecting agent is an effective method, but water proof materials should be introduced to improve resin's water resistance. With melamine being replaced by urea partly, the cost of MF resin can be reduced. If better aging resistance is obtained, the ratio of M/F should come to over 40: 60. Introducing metal ions, increasing akalinity, polymerization degree and in addition , adding curing accelerant are the main methods, while increasing curing speed and lowering curing temperature are the development trend of PF resin adhesive. Low toxic and high quality artificial plate adhesive will gain more and more attention.