Synthesis And Characterization Of Calix[4]resorcinarene-based Bi-functional Hyper-structure Photorefractive Molecule

The term “photorefractive”(PR) loosely characterizes a material that exhibits atemporal change of its refractive index induced by illumination. Hyper-structuredmolecule (HSM), which has a complex three-dimensional molecular structure,contains different photorefractive function components through chemical bonds. Thematerial achieves photorefractive effect by the synergy of functional components.Calix[4]resorcinarene (CRA), which can be easily prepared, has diverse derivatives.And its unique three-dimensional structure helps its derivatives to remain amorphousstate.In this paper, we designed and synthesized a kind of hyper-structure molecule,which have a core of CRA derivative and linked with Disperse Red1providingelectro-optical response. We also designed and synthesised an other series ofbi-functional hyper-structure photorefractive molecule, which have a same core butselecting carbazole derivative as the charge transport group and nitroazo benzeneproviding electro-optical response. The chemical structure and thermal performanceof all the intermediates and final products were characterized, and we discussed theesterification rate of some final products.Firstly, using Disperse Red1as NLO chromophore, CRA-DP HSM wassynthesized and characterized. We first derivatized the CRA by changing eighthydroxyl groups of the upper edges into higher reactive carboxyl groups, whichcontains two outwardly carbons with lower steric hindrance. Then we introducedelectro-optical response group Disperse Red1by esterification of the acylatedCRA-COOH, preparing photorefractive hyper-structure molecules with electro-opticalresponse. And we characterized the structure and performance by1H (13C) NMR,Ft-IR, EA, UV-vis, GPC, TG and other methods. Caculated from elemental analysisresults, the average amount in each molecule is5.6, esterification is70%, UV-visibleabsorption spectra shows azo group absorption peak was at482nm. GPC spectrum ofCRA-DP shows the molecule dispersity index was1.22, TGA showed itstemperature of decomposition was250℃.Secondly, using carbazole group as transporting group and nitro azobenze asNLO chromophore, bi-fuanctional PR HSM CRA-C-Cz(100-x)-Azo(x)were synthesized,where x represent the mole percent of feeded NLO chromophore among totalmonomer. The charge-transporting group carbazole derivative (Cz-OH) andelectro-optical components bonded to the azo group carbazole derivative (Cz-Azo). were synthesized.Then, CRA-C-Cz(100-x)-Azo(x), where x=100,75,50,25,0, wereprepared by the esterification reaction of CRA-COOH with Cz-OH and Cz-Azo,respectively. And we characterized the structure and performance by1H(13C) NMR,IR, EA, UV-vis, GPC, TG and other methods. Caculated from the elemental analysisresults, the introduction of amount of function group of CRA-C-Cz(100)-Azo(0), andCRA-C-Cz(0)-Azo(100)are5.1and4.9, respectively. In other words, their esterificationrates are64%and61%, respectively. GPC results showed the molecular dispersityindex were less than1.22. All the temperature of decomposition were higher than250℃.