Study On Synthesis Method Of Chiral Polyaniline

This thesis includes two parts.The first part optimized the synthesis conditions of three preparation ways,self-assembly combined with oligomer-assisted method,interfacial polymerization method,and secondary doping method to obtain the optimal conditions for synthesizing doped polyaniline under each method;The second part synthesized of 8 kinds of aniline derivative polymers by self-assembly combined with oligomer-assisted method.Objective:To optimize the synthesis conditions of chiral polyaniline with different synthesis methods.Methods:(1)Two kinds of single chiral polyaniline were synthesized,adopting the self-assembly combined oligomer-assisted method,using aniline as the monomer,single configuration camphorsulfonic acid as dopant and inducer,DDQ as oxidant,N-phenyl-1,4 p-phenylenediamine as oligomer.Several factors,including the molar ratio of CSA and aniline,ways to dissolve raw materials,product processing method,raw materials and dopant,etc.,were optimized to get the best synthesis conditions of single chiral polyaniline.Technical means such as UV,IR,SEM,TEM,CD,XRD were used to characterize the structure,morphology and chirality of products.(2)Two doped polyanilines were synthesized,using interfacial polymerization method,aniline as monomer,single configuration camphorsulfonic acid as dopant,APS as oxidant.The washing conditions were optimized.UV,IR,SEM,TEM,CD,XRD,etc.were used to characterize their structure,morphology and chirality.(3)Three emeraldine base polyanilines with known average molecular weight range were used as raw materials to prepare the doped PANI for the first time.Using the secondary doping method,with a single configuration of camphorsulfonic acid as a dopant,by changing the solvent purity,reaction treatment method,and the mole of reactants,doped polyaniline was synthesized in THF solution and characterized by UV spectroscopy.(4)Adopting the self-assembly combined oligomer-assisted method,using aniline derivatives(o-toluidine,m-toluidine,o-ethylaniline,m-ethylaniline)as monomers,single configuration camphorsulfonic acid as dopant,DDQ was used as an oxidant,N-phenyl-1,4 p-phenylenediamine was used as an oligomer to assist in the synthesis of 8 kinds of aniline derivative polymers.UV spectroscopy was used for characterization.Results:(1)For the self-assembly combined oligomer-assisted method,the optimal conditions for the synthesis of chiral polyaniline were as follow:the molar ratio of CSA and aniline was 10:1;ultrasonic dissolution;after the self-assembly reaction was completed,the reaction solution was first notarize evaporation about half of the solvent,added the poor solvent methanol and placed it for 48h to prolong the self-assembly time;otaried evaporation and added methanol to centrifuge and wash 3 times,and vacuum dried at 40? for 24h to obtain chiral polyaniline.(2)The optimal conditions for synthesizing doped polyaniline by the interfacial polymerization method were as follow:the molar ratio of CSA and aniline was 20:1;after the polymerization was completed,centrifuged and washed with distilled water three times,and then washed methanol and ethanol once and centrifuged;vacuum dried at 40? for 48h to obtain the doped polyaniline with reticulated morphology.(3)The optimal conditions for the synthesis of doped polyaniline by the secondary doping method were as follow:using emeraldine base polyaniline with an average molecular weight range of 15000 as the raw material;THF as the solvent;the ratio of EB to CSA was 1:16(calculated by aniline);300rpm vortexed and shaked for 3h,then left standing for 24h.(4)Compared with polyaniline,aniline derivative polymers synthesized by self-assembly combined with oligomer-assisted method had better solubility in organic solvents;due to the steric effect of methyl(or ethyl),the characteristic absorption peak response value at 430nm had different degrees of reduction or no characcteristic absorption peak at 430nm,and the absorption peak at 800nm appeared blue shift.Conclusion(s):(1)Self-assembly combined with oligomer-assisted method could synthesize chiral polyaniline fiber with obvious spiral structure and good CD signal;(2)Interfacial polymerization method could obtain doped polyaniline fiber with reticulated morphology and large surface area;(3)The synthesis of doped polyaniline using emeraldine base polyaniline with known average molecular weight range was a feasible way,but more systematic experiments are needed to analyze the influence of average molecular weight range on the synthesis of doped polyaniline;(4)Compared with polyaniline,aniline derivative polymers synthesized by self-assembly combined with oligomer-assisted method had better solubility in organic solvents,and the introduction of substituents could also provide more places for the structural modification.