热塑性酚醛树脂的13C NMR表征

采用一种新型环保工艺合成了热塑性酚醛(phenol novolac,PN)树脂,并采用13C NMR方法对其分子结构进行了分析,由谱图中各峰积分值定量计算出了o-o、o-p、p-p结构、支化结构、游离苯酚和醚键等其它结构所占比例分别约为19.42%、46.21%、22.32%、3.13%、4.24%和4.69%。与常规工艺生产的PN相比并无大的变化,但新型工艺从根本上解决了常规工艺带来的高浓度含苯酚废水污染的问题。研究发现催化剂浓度的提高可以减少支化结构的产生,反应温度的提高有利于o-o结构的生成,随着反应时间的延长,o-o、o-p、p-p3种结构增多。

Structural Characterization of Phenol Novolac Resin by 13C NMR Spectroscopy

Phenol novolac(PN) resin was synthesized with a new environmental technology and its structure was characterized by 13C NMR spectroscopy.Using the integral value of each peak,the abundance ratio of o-o,o-p and p-p structures,branching structure,free phenol and ether link were found to be 19.42%,46.21%,22.32%,3.13%,4.24% and 4.69%,respectively.The PN structure was almost the same as that produced by the conventional method.But the new technology could solve the problem of waste water with high phenol concentration usually produced by the conventional technology.Experimental results showed that the branching structure could be reduced by increasing the amount of catalyst, that high reaction temperature was favorable to the formation of o-o structure,and that the increase of reaction time could increase the amount of o-o,o-p,p-p structures.