Synthesis And Investigation Of Hydrogen-bonded Functional Supramolecular Side-chain Liquid Crystalline Polymers

In this dissertation,we have designed and synthesized a series of hydrogen-bonded functional supramolecular side-chain liquid crystalline polymers(SCLCPs).The phase behavior,Aggregation-induced emission(AIE)effect,isomerization process of the small molecules(Z-CNBP,E-CNBP)and functional SCLCPs were investigated.Concurrently,the self-assembled structure from hydrogen-bonded copolymers containing P4VP,linear surfactant pentadecylphenol(PDP)and dendritic molecule(12CBP)was preliminary researched.The main topics of this paper are as follows:(1)Dendritic cyanostilbene derivative CNBP containing phenolic end group were designed and synthesized.The photophysical properties of CNBP were investigated by fluorescence and ultraviolet(UV)spectra.The corresponding Z isomer(Z-CNBP)shows intense fluorescence in solid or liquid crystalline states,exhibiting typical AIE effect,while E-isomer is nonfluorescent.Z-CNBP and E-CNBP can convert to each other via the photo and thermal stimuli.(2)The functional supramolecular polymers P4VP(Z-CNBP)X and P4VP(E-CNBP)X were prepared.Their self-assembly structures in bulk were characterized by means of FT-IR,DSC,POM and SAXS techniques.P4VP(Z-CNBP)X possess hexagonal columnar phase at x>0.3,while P4VP(E-CNBP)X show lamellar phase at x<0.7.The Z-E isomerization of CNBP could induce fast and obvious photochromic fluorescence(PCF)in the P4VP(Z-CNBP)x and P4VP(E-CNBP)x films.(3)The self-assembled structures from hydrogen-bonded copolymers containing P4VP and PDP and 12CBP were investigated.The ternary complexed system is named as P4VP(12CBP)x(PDP)y(x+y=1).Despite the different shape and self-assembled properties from 12CBP and PDP,FT-IR,DSC,POM and SAXS studies reveal that the ternary supramolecular copolymer system forms a homogenous phase.At x ? 0.5,P4VP(12CBP)x(PDP)y possesses homogenous hexagonal columnar phase.The lattice parameter decreases gradually with decreasing x.At x<0.5,P4VP(12CBP)x(PDP)y is amorphous with layer like fluctuation,instead of columnar phase.In this case,the relative grafting density of linear side chains is larger than that of dendritic side chains,which could not stabilize the columnar phase formation.Meanwhile the existence of small amount of 12CBP tends to interrupt the lamellar mesophase formation.