AIE材料合成、表征及其在防伪印刷中的应用

Synthesis and Characterization of AIE Materials and Their Application for Anti-Counterfeit Printing

荧光防伪印刷技术即是将特殊的荧光印刷油墨融合到标识上,并借助额外的激发光才能找到加密信息,从而起到防伪作用。荧光防伪多在膜或固态下使用,因此需要荧光油墨在这些状态下具有强的发光性质。聚集诱导发光(Aggregation-Induced Emission,AIE)分子是一类在单分子状态下发光较弱甚至不发光而在聚集状态下表现出强烈发光的分子。而水杨醛席夫碱分子作为一类合成简单、荧光强度高的典型AIE分子,具备刺激响应荧光机制,其在酸碱环境下表现出不同的荧光特性使得这一类分子在防伪印刷领域有突出的表现。本论文通过水杨醛与胺的亲核加成反应一步制备水杨醛席夫碱AIE分子,并进一步展示其在防伪印刷中的应用;通过对该分子在不同环境下的表征,阐明其AIE特性和刺激响应荧光机制在防伪印刷应用中的作用。本实验原料易得、安全、成本低廉,所需仪器常规,符合实验教学要求,通过本实验训练,学生不仅掌握了席夫碱类化合物的制备方法,同时也学习了水杨醛席夫碱分子的刺激响应荧光在防伪印刷中的应用。结合课堂教学和拓展阅读,使学生进一步了解防伪印刷产品的特性以及设计思路。

Fluorescent anti-counterfeit printing technology is applied in the special fluorescent printing ink used for logos,which in conjunction with additional light excitation to expose the encrypted information play an anticounterfeiting role.Fluorescent anti-counterfeiting is mostly used in film or solid state;therefore,it is necessary for fluorescent ink to have strong luminescent properties in both states.Aggregation-induced emission(AIE)molecules are a class of molecules that emit weak or even no light in a single molecule state and exhibit strong luminescence in an aggregated state.As a typical AIE molecule with simple synthesis and high fluorescence intensity,the salicylaldehyde Schiff base molecule has a stimulus-responsive fluorescence mechanism.Its different fluorescence characteristics in acid-base environments make this kind of molecule outstanding in the field of anti-counterfeit printing.In this study,the salicylaldehyde Schiff base AIE molecule was prepared by a one-step nucleophilic addition reaction of salicylaldehyde and amine,and its application in anti-counterfeit printing was further demonstrated.Through the characterization of the molecule in different environments,the role of its AIE characteristics and stimulus response fluorescence mechanism in anti-counterfeit printing applications was elucidated.The experimental raw materials are easy to obtain,safe,low cost,and the required instruments are routine,which meets the requirements of laboratory teaching.Through this experimental training,students not only master the preparation method of Schiff base compounds,but also learn the application of stimulus response fluorescence of salicylaldehyde Schiff base molecules in anti-counterfeit printing.The combination of classroom teaching and extended reading,enables students to further understand the characteristics of anti-counterfeit printing products and design concepts.