Synthesis And Characterization Of Tetraphenylethylene Small Molecule And Polymer

Aggregation-induced Emission(AIE)refers to the phenomenon that molecules exhibit weak emission even no light in the dispersed state(such as dilute solution),but can show strong fluorescence in the aggregate state(such as solid film).The preparation of small molecule derivatives with AIE effect can effectively solve the problem of low luminous efficiency caused by aggregation of traditional luminescent materials in practical application.Compared with AIE small molecule,AIE polymer has better filmforming property and processability,and has a broad application prospect.Therefore,through molecular design and regulation,the preparation of small molecules and polymers with AIE properties has important scientific significance and application value.In this dissertation,small molecules and polymers of tetraphenylethylene derivatives with AIE properties were synthesized,and the photophysical characteristics and phase transition properties of the samples were studied in detail.The main research findings are as follows:(1)Tetraphenylethylene derivatives(TPE-C12 and TPE-2C12)with fan-long alkyl tail chains were synthesized.The results of spectroscopic and thermogravimetric experiments show that both TPE-C12 and TPE-2C12 have typical aggregation-induced emission properties and good thermal stability.TPE-C12 can develop an ordered selfassembly structure at room temperature,and by slowly volatilizing it from a chiral solvent,it can also induce the chiral self-assembly of TPE-C12 molecules,resulting in circularly polarized luminescence.TPE-2C12 exists as a viscous liquid,which is a liquid luminescent material at room temperature.(2)Polynorbornene polymers(P-TPE-C12)containing AIE side groups were prepared by introducing TPE-C12 into the polymer system as a side chain.The results of fluorescence spectra and thermogravimetric experiments show that the polymer has obvious aggregation induced luminescence property and good thermal stability.The tensile test results show that the polymer has good mechanical properties,and the shape memory performance test results show that P-TPE-C12 has a double shape memory effect,can effectively remember 300% of the high strain and has a high shape fixation rate and shape recovery rate.