Synthesis And Characterization Of Multiple Environmental Responsive Light-emitting Molecules: Self-assembly And Applications

One of the goals of contemporary science is to design and synthesize materials with expectedfunctions by the judicious atomic or molecular design, and then the structure of the organic systemhas a broad research space, which has been widely applied in the field of biochemistry and materialchemistry. Currently, there are basically two ways for people to give some special properties in theprocess of research materials, one way is to add or dope the natural organic material and make ithave certain functional, another way is to directly modify the material surface, which will endow itwith the function we need. This paper is to mainly use different groups of small molecules tosynthesize molecular skeleton with optical features, then the polymer has some certain functions bymodifying the branched chain, such as, pH and temperature-responsive hydrophilic or hydrophobic,etc. It is a blue material or compound with AIE characteristic, which will form different micelle indifferent solution, and we characterize the micelle morphology and particle size by using TEM andDLS. We also finally discuss the outlook and the future prospects in this field. The main experimentresults are illustrated as below:(1)First, we have designed and synthesized a carbazole-fluorene-based polymer brush, thenmodified the carbazole. After that, we introduced8-hydroxyquinoline to make the polymerpH-responsive. We have studied the particle size and morphology evolution of micelles formed byself-assembly in different mixture solvent, temperatures and pH values. Then we get the bestconditions for forming micelles.(2)We have designed and synthesized multiple environmental responsive polyfluorenes byusing the polyfluorenes composed by fluorene molecule, functional side chain and AIE molecular.Then we have studied aggregation morphology of the polymers in the mixed solvent, and alsostudied the spectral characteristics of polymers containingdifferent AIEsegmernts. It can make thepolymer to be water-soluble and temperature-responsive by introducing the poly(N-Isopropylacrylamide) into the polymer chain.(3)Design and synthesis of three probe molecules with charge transfer characteristics ispresented in detail, and two of them has AIE properties. We studied the aggregation of two compounds in different solvent. Because the probe molecules has charge transfer characteristics, wealso studied fluorescence changing and quantum efficiency of three probes in different solvents withdifferent dielectric constants. Lastly, we have usd the titration experiments to detect explosive, andthen calculated the detection limit of explosive by plotting curves of these two probes at100%tetrohydrofuran solution of90%water.. The performance of compound TPE-BT-CZ in detection ofPA is much better than that of compound TPE-BT-TPE both in quenching constant and detectionlimits, which indicates that the introduction of carbazole-based electron donor group to formasymmetric molecular structure for the entire probe molecules is helpful to promote its detectionperformance in some degree.