NaOH用量对PUF共缩聚树脂结构和性能的影响

以13^C核磁共振分析（13^C NMR）和基质辅助激光解析电离飞行时间质谱（matrix-assisted laser desorption／ionization time-of-flight mass spectrometry．MALDI—TOF—MS）为手段．研究了不同的NaOH／P物质的量比（nNaOH／nP）条件下合成的苯酚-尿素-甲醛（PUF）共缩聚树脂的结构特征，通过压制胶合板，进一步评价了nNaOH／nP变化对PUF共缩聚树脂的影响。13^C核磁共振和MALDI—TOF—MS结构分析结果显示，在本研究范围内改变碱性条件对PUF共缩聚树脂的结构构成无显著影响；合成的PUF共缩聚树脂结构仍是以酚醛树脂为主体，特别是聚合物的链接方式；胶合性能研究结果表明，在尿素／甲醛／苯酚物质的量比不变的条件下，在一定范围内增加NaOH的用量，PUF树脂干状和湿状胶合强度增加显著，这一合理的范围应小于nNaOH／nP=0．53，超出这一范围后，随着nNaOH／nP的增加，树脂的胶合性能快速下降，但仍在可以接受的范围内。

Influence of NaOH/phenol mole ratio on the structure and performance of Phenol-Urea-Formaldehyde resin

The structure of phenol urea-forrnaldehyde（PUF） co-condensate resin prepared at different NaOH/P mole ratiu was studied by carbon 13 nuclear magnetic resonance （13^C NMR） spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF-MS）.Then the influence of NaOH/P mole ratio on the performance of PUF resin was further evaluated by preparing the PUF-bonded plywood panel. 13^C NMP, spectroscopy and MALDI-TOF-MS indicated that the structure of PUF resins is similar at different NaOH/P mole ratio. Evaluation of laboratory plywood showed that the dry and wet strength obviously increase with the NaOH/P mole ratio within a certain value. The mole ratio of NaOH/P should he less than 0.53,mole ratio over this value can cause the performance of PUF resin to be decreased drastically,but is also acceptable.