Synthesis And Fluorescent Properties Of A New Pizeochromic And Anion Multiple-responsive Polymer

Stimuli-responsive materials would self-driven change the physical and chemicalproperties, with the change of external stimuli. In rescent years, stimuli-responsivematerials, among new flourscent materials, have aroused more attention for thecharacteristic advantage of rapid responsive, hoping applied to drug controlled, diseasediagnosis and biosensor etc. Moreover，the interest towards small molecules capables ofself-assembley leading to gelation has increased intensively for the wide range ofapplication. This paper, consists of three chapters, designed and synthesized a newpizeochromic and anion multiple-responsive polymer, studied the mechanism ofpizeochromism and fluorination.Chaper1: Introduced the definition, classification, functional mechanism and thespecific applications of stimuli-responsive marertials. Moreover, emphasized the researchprogress of pizeochromic materials and anion responsive materials.Chapter2: Pizeochromic materials, which can switch the molecular staking mode byforce stimulation with the change of solid emission, have important applications inrecording materials and sensors. Given anthryl has a mutual intermolecular π-π effect andwidely used in the design of pizeochromic materials, we have designed and synthesized apizeochromic material with high degree of fluorescence emission2-(anthracen-9-yl)-4,5-diphenyl-1H-imidazole (ADPI). Different luminescent single crystals of2-(anthracen-9-yl)-4,5-diphenyl-1H-imidazole (ADPI) were obtained through the construction ofdifferent stacking modes with the aid of intermolecular interactions. Both the fluorescenceand the stacking mode of the crystals can be reversibly tuned by mechanical and thermalforces to render ADPI piezochromic, which represents a unique example of reversiblycontrolled solid emission. Based on the study of ground and heated state of C1crystal, wefound that the regulation of π-π stacking between the anthracene planes by mechanical andthermal forces is suggested to be the main driving force for the piezochromic character. Inaddition, the power also exhibits comparatively pizeochromic properties similarly crystalsby mechanical and thermal forces.Chapter3: Designed and synthesized a series of imidazole-conjugated derivatives,ADPI with cyclohexane-specific formation of organic gel: cyclohexane solution of ADPI,through heating and slowly cooling, can form yellow organic gel. By electron microscopySEM, TEM and confocal fluorescence microscope, we studied ADPI xerogel’s topography and fluorescence micrographs. Interestingly, sensitive and selective response to fluorideanion of ADPI gel (pale yellow, green fluorescence) induces precipitation of a red solidwith red emission, and successfully obtained the corresponding single crystal precipitation;and the formed product was identified by1H NMR and X-ray single crystal analysis. Aminimum of0.2equiv fluoride anions is required to destroy the gel. Moreover, the gel canbe recovered through removal of fluorides by addition of methanol or water. In addition,we studied the may mechanism of fluorination.