Synthesis And Characterization Of The Ionic Polymer Containing Pyridine Groups

Liquid Crystalline Ionomers(LCIs),a kind of polymers with ions and the properties of liquid crystals,have been developed into a class of ionic polymers on the basis of liquid crystal polymers and ionomers.As a new kind of functional polymer material,LCIs involve many subject directions such as chemistry,physics,electronics and materials science and other subject categories.LCIs have unique physical properties of electromagnetic and optical,and have good chemical stability and mechanical properties.LCIs not only have important theoretical significance and academic value but also have the potential application area such as information,military,optics,blends,composite materials,and so on.In this dissertation,three monomers were synthesized including biphenyl-4,4’-diyl diisonicotinate(M1),hexahydrofuro(3,2-b)furan-3,6-diyl bis(2-bromopropanoate)(M2)and hexane-1,6-diyl diisonicotinate(M3).A series of LCIs(P1 series)were synthesized using the monomers M1,M2 and M4 as raw materials.Another series of LCIs(P2 series)were prepared using the monomers M1,monomer M3 and monomer M4 as raw materials.The P3 series of LCIs were synthesized by the substitution reaction of fluoroboric acid and P1 series;and the P4 series of LCIs were synthesized by the substitution reaction of hexafluorophosphoric acid and P1 series.Similarly,the P5 and P6 series of LCIs were synthesized by an ion exchange reaction using P1 series of LCIs,trifluoroacetic acid and trifluoromethanesulfonic respectively.The P7,P8,P9,and P10 series of LCIs were respectively synthesized by an ion exchange reaction between the mother polymers(P2 series of LCIs)and corresponding reagents including fluoroboric acid,hexafluorophosphoric acid,trifluoroacetic acid and trifluoromethanesulfonic acid.Especially,these three monomers,two series of polymers and eight series of liquid crystalline polymers were first prepared.So the study in this dissertation was original.The structures and properties of the obtained monomers and polymers were investigated by FT-IR spectroscopy,1H-NMR spectroscopy and 13C-NMR spectroscopy.The thermal properties and mesogenic texture were characterized by use of differential scanning calorimetry(DSC)and polarized optical microscopy(POM).The experimental results showed that the chemical structures of all the synthesized monomers,two series of polymers and eight series of liquid crystalline polymers were consistent with the molecular design.The research in this dissertation provided some theorical basises and necessary technological supports for futher study on LCIs.