对于木板粘合剂的自我中和的胺-尿素-甲-酸树脂
Xuedong Xi1, Antonio Pizzi2, Hong Lei3
1Yunnan Key Laboratory of Wood Adhesives and Glued Products, College of Material Science and Engineering, Southwest Forestry University, Kunming 650224, China.
Polymers
|July 13, 2024
概括
对于MUF木材粘合剂而言,一种新的自我中和系统保持了最佳的pH值,防止了降解并增加了粘合强度. 这种缓冲系统增强了碎片板和合板的耐用性,特别是在暴露在水中后.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 木材复合材料 木材复合材料
背景情况:
- 像MUF树脂这样的木材粘合剂可能变得过于酸性,损害了结合强度和长期耐用性.
- 酸性条件可以降解粘合剂接口上的木材组件,导致关节故障.
- 现有的缓冲系统可能与MUF树脂不兼容或不够有效.
研究的目的:
- 开发和评估MUF木材粘合剂的自中和缓冲系统.
- 为了提高MUF树脂的pH稳定性,使用有机酸和.
- 为了提高木制面板的机械强度和耐用性,用修改后的粘合剂粘合.
主要方法:
- 将酸和六胺 (或其他有机基) 纳入MUF树脂中,以创建酸缓冲区.
- 测试修改后的MUF粘合系统的pH稳定性.
- 在干燥和潮湿条件下 (热水,沸水) 评估碎片板和合板的粘合强度 (内部粘合和切割强度).
主要成果:
- 缓冲系统成功地保持了粘合剂的pH值在4.0的临界值以上.
- 对于碎片板和合板,都观察到结合强度的显著增加.
- 碎片板IB强度增加了15-17% (干燥) 和82% (沸). 合板的剪切强度增加了37% (干燥) 和90% (热水).
结论:
- 自中和系统有效地防止木材和粘合剂接口的pH诱导降解.
- 来自酸的增强交叉链接和改善的pH稳定性有助于优越的结合线强度和耐用性.
- 这种缓冲方法提供了一种可行的方法来提高MUF结合木制品的性能和寿命.
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