Preparation And Characterization Of Hyperbranched Polytriazole And Polysulfone Functionalized With Triazole And Phosphonic Acid Groups

Triazole polymers attract the interests of many researchers in academia and industry due to their potential applications in many fields.The copper(1)catalyzed cycloaddition of alkynes and azides of click reaction is an effective means to build triazole polymers.In this thesis,the "A2+B3" method is applied to the synthesis of two series of hyperbranched polytriazole(hb-PTril and hb-PTri2).The hb-PTril is synthesized via click reaction from 1-azido-2-(2-azidoethoxy)ethane(monomer A2?)and 1,3,5-tris(propargyloxyl)benzene(monomer B3)catalyzed by copper sulfate pentahydrate(CuSO4·5H2O)and sodium ascorbate(NaAsc).1-azido-2-(2-azidoethoxy)ethane(monomer A2?)is synthesized from 1-bromo-2-(2-bromoethoxy)ethane and sodium azide(NaN3).1,3,5-tris(propargyloxyl)benzene(monomer B3)is synthesized from phloroglucinol and 3-bromo-1-propyne.The hb-PTri2 is prepared by click reaction from 1,2-bis(2-azidoethoxy)ethane(monomer A2p)and 1,3,5-tris(propargyloxyl)benzene(monomer B3)catalyzed by CuSO4·5H2O and NaAsc at 25? for 30 h under nitrogen atmosphere.1,2-bis(2-azidoethoxy)ethane(monomer A2p)is obtained by 1,2-bis(2-chloroethoxy)ethane and NaN3.To understand the reaction process of hyperbranched polytriazole,the effect of different monomer molar ratios and different reaction time of hb-PTril is also discussed.The structures the monomers and polymers are characterized by using 1H NMR.The hb-PTril(a-e)are prepared based on different monomer molar ratios and different reaction time,and the molecular weights(M,)are tested.The Mw and polydispersity index(PDI)of hb-PTril(a-e)are in the range of 16000-35000 Da and 1.40 to 2.15,respectively.The actual degrees of polymerization(Xn)of hb-PTril(a?e)are in the range of 96 to 211,and hb-PTril(c)shows the highest yield(90.2%),with the monomer molar ratio of n(A2?):n(B3)= 3:2 and 30 h reaction time.The hb-PTril(c)and hb-PTri2 membranes are obtained by solution casting.Thermal stability,oxidative stability,mechanical property and microstructure are systematically investigated.The hb-PTril(c)and hb-PTri2 membranes show excellent thermal stabilities and chemical stabilities.Based on mechanical properties tests,the tensile strengths at break of hb-PTril(c)and hb-PTri2 are 15.35 MPa and 29.09 MPa,respectively.Young's modulus of hb-PTril(c)and hb-PTri2 are 1320 MPa and 1303 MPa,respectively.At last,hb-PTril(c)and hb-PTri2 are investigated their fluorescent property with multiple metal ions(Cr3+,Cd2+,Ni2+ K+,Li+,Na+ and Pb2+).For hb-PTril(c)and hb-PTri2.Cr3+ leads to 91.29%and 83.20%fluorescence quenching efficiency,respectively.Thus,the polymers can be used as selective fluorescence sensors for Cr3+ detection.In addition,three novel different side chain length polysulfones functionalized with triazole and phosphonic acid groups(PSF-TriPA-1.PSF-TriPA-2 and PSF-TriPA-3)are prepared.PSF-TriPA-1,PSF-TriPA-2 and PSF-TriPA-3 are obtained orderly by chloromethylation,azidation,click reaction and hydrolysis.Three different side chain length azidation polysulfones(PSF-N3-1,PSF-N3-2 and PSF-N3-3)are synthesized from chloromethylation polysulfone.NaN3,3-azido-l-propanol and 6-azido-1-hexanol.After three times of click reactions between PSF-N3-1(PSF-N3-2 or PSF-N3-3)and diethyl(4-ethynylphenyl)phosphonate,PSF-PO(OEt)2-1(PSF-PO(OEt)2-2 or PSF-PO(OEt)2-3)are obtained with different side chains containing triazole and phosphonate groups.At last,the target products,(PSF-TriPA-1,PSF-TriPA-2 and PSF-TriPA-3)are obtained after hydrolysis.The structures of monomers and polymers are characterized by 1H NMR.PSF-TriPA-1,PSF-TriPA-2 and PSF-TriPA-3 membranes are prepared by solution casting.Proton conductivities,thermal stabilities and oxidative stabilities of membranes are characterized.At 100 ? and 90%relative humidity(RH),the proton conductivity of PSF-TriPA-3 membrane achieves 15.369 mS cm-1,2.8 times and 1.8 times higher compared with that of PSF-TriPA-1 and that of PSF-TriPA-2,respectively.The increasing distance between the hydrophilic groups and ploymer backbone promotes the formation of nano-phase separation,constructs continuous proton channels,and increases proton conductivity.Besides,PSF-TriPA-1,PSF-TriPA-2 and PSF-TriPA-3 membranes show excellent thermal stabilities and chemical stabilities in thermal stability analysis and Fenton tests.