基于苯乙烯腈结构的可逆力致变色化合物的合成及性能  

Synthesis and Characterization of New Cyanostilbene-Based Compound Exhibiting Reversible Mechanochromism

作　　者：毛文纲[1] 陈康[1] 欧阳密[1] 孙璟玮[1] 周永兵[1] 宋庆宝[1] 张诚[1] 

机构地区：[1]绿色化学合成技术国家重点实验室培育基地浙江工业大学化学工程与材料学院,杭州310014

出　　处：《化学学报》2013年第4期613-618,共6页Acta Chimica Sinica

基　　金：国家重点基础研究发展计划(973计划)前期专项项目(No.2010CB635108;2011CBA00700);国际科技合作重点项目计划(No.2012DFA51210);国家自然科学基金(Nos.51203138;51273179)资助~~

摘　　要：合成了一种棒形的化合物4,4'-二(α-腈基-4-苯丙氧基苯乙烯)联苯(Ben-DCSB),利用核磁共振(NMR)、质谱(EI-MS)、傅里叶变换红外光谱(FT-IR)和元素分析等对其进行了结构表征.对Ben-DCSB重结晶粉末进行研磨后,其发光颜色从蓝绿色变成黄绿色,荧光量子效率(ΦF)从初始的52.7%变为38.7%,表明该化合物具有力致变色性质.扫描电子显微镜(SEM)、X-射线衍射(XRD)和荧光寿命等测试结果显示,这种现象是由于在外界环境刺激下改变了Ben-DCSB在聚集态下的分子堆积结构所造成的.研磨后的样品暴露在溶剂蒸气(乙醇、二氯甲烷、四氢呋喃或丙酮)或100℃温度下放置2 min又能转换回初始状态的蓝绿色荧光,表明化合物研磨后的样品具有气致和热致变色性能,且展现出可逆变色性能.对该化合物进行多次"力-溶剂蒸气刺激"和"力-热刺激"循环实验,结果显示其具有很好的荧光可逆转换性能.热分析结果显示化合物Ben-DCSB在194℃和212℃间存在向列相(纹影织构)的液晶态;其热分解温度为362℃,表明该化合物具有较好的热稳定性.A rod-like molecules,4,4'-bis(α-cyano-4-phenproalkoxylstryl)biphenyl(Ben-DCSB),has been synthesized and characterized by nuclear magnetic resonance(NMR),electron ionization-mass spectrometry(EI-MS),Fourier transform infrared(FR-IR) and elemental analysis.Ben-DCSB presents excellent mechanochromism behaviors.Recrystallized blue-green Ben-DCSB powder are changed into relatively yellow-green with the fluorescence quantum efficiency(ΦF) obviously converting from original 52.7% to 38.7% after being ground.Photoluminescence(PL) spectra of the samples obtained under different conditions(ungrind and grind) show the maximum emission wavelength(λem) has a significant red-shift as high as 23 nm after grinding.Observing the morphological structure of Ben-DCSB under different aggregative state by using scanning electron microscopy(SEM),the results indicate that the damage on surface morphology which is caused by external stimuli can be restored by exposing ethanol vapor or heat treatment.The X-ray diffractometry(XRD) measurements,the ungrind dye displays indicative of well-defined microcrystalline-like structures,and grinding dye is amorphous feature in this state.These observations further indicate the mechanochromism originates from the altering mode of molecular packing from the high-order to disorder by grinding.Time-resolved fluorescence spectrofluorometer analysis of ungrind ande grind dye show the attenuation exponential increases from single exponential of ungrinding to double-exponential of grinding.The result further demonstrate order degree of the grind sample decreases.The ground powder return to original colour by fuming with solvent(ethanol,dichloromethane,tetrahydrofuran or acetone) or heating at about 100 ℃ for 2 min.And the PL spectra show these samples can return original λem(485 nm).Moreover,dye Ben-DCSB indicates good reversibility of fluorescence conversion upon grinding-fuming and grinding-heating processes.XRD measurements indicate that the amorphous sample obtained by grinding can revert to cryst

关 键 词：力致变色 可逆 荧光材料 分子堆积 苯乙烯腈 

分 类 号：O625.67[理学—有机化学]