基于萘酰亚胺荧光增白剂的聚合型返黄抑制剂的合成及应用

Synthesis and application of polymeric yellowing inhibitor based on naphthalimide fluorescent brightening agent

将4-溴-1,8-萘酐与乙醇胺进行酰胺化,再在萘环4-位引入乙氧基供电子基团,合成了萘酰亚胺荧光增白剂(FBA)。以三聚氯氰为交联单体,将紫外光吸收剂(UVA)2,4-二羟基-二苯甲酮与萘酰亚胺引入同一分子中,合成了一种新型的高得率浆返黄抑制剂。并使其与丙烯酰胺按照一定比例聚合,得到一种能溶于水的聚合型返黄抑制剂。采用红外光谱和核磁氢谱对合成物质进行了结构表征,运用紫外光谱、荧光光谱测试其光学性质。将制备的3种助剂分别涂布于纸张表面,通过紫外光加速返黄实验考察其对纸张的返黄抑制效果。结果表明,当3种助剂都使用最佳用量时,经26h紫外光加速老化后,抑黄效果依次排序为:返黄抑制剂聚合物>返黄抑制剂单体>萘酰亚胺FBA。

Naphthalimide fluorescent brightening agent （FBA） was synthesized from 4-bromo-1,8-naphthalic anhydride and ethanolamine via amidation, then joining ethoxy electron-donating group into 4-bit of naphthalene ring. With cyanuric chloride as the crosslinking monomer, a new yellowing inhibitor for high-yield pulp was synthesized through joining the ultraviolet absorber （UVA） 2,4-dihydroxy-benzophenone and naphthalimide fluorescent brightener in the same molecule. Then a water-soluble yellowing inhibitor polymer was obtained by copolymerization between it with acrylamide. The molecular structures were characterized by IR spectra and 1 H NMR;optical properties were measureed by UV spectra and fluorescence spectra. Coating the three prepared additives according to a certain concentration on the surface of paper, their yellowing inhibition effect were studied by UV accelerated yellowing experiments. The results show that： when the three additives use the optimal dosage, after 26h UV accelerated aging, the yellowing inhibition effect of them followed the order ： yellowing inhibitor polymer 〉yellowing inhibitor monomer 〉naphthalimide FBA.