不同浸润度聚苯胺的制备及性能

摘要

Polyaniline (PANI) with different wettability was synthesized by emulsion polymerization using sodium dodecyl sulfate (SDS),hexadecyl trimethyl ammonium bromide (CTMAB),poly (ethylene oxide)(PEG) as dispersants.Influence of different types of dispersants on the performance of PANI was studied.The PANI was analyzed by Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),Water Contact Angle(WCA),FT IR spectra,UVVis spectra,laser particle size analyzer,etc.The electrochemical performance was researched by circulation current-voltage,AC impedance experiments.Results showed that each sample of PANI was doped with hydrochloric acid,the hydrophilicity of PANI using PEG as the dispersant was the best,CTMAB was the second and SDS was the worst.Using PEG as a dispersant can reduce the particle size of PANI and improve the regularity as well as the conductivity of PANI.The hydrophilic head group of anionic dispersant SDS is negatively charged,which is easy to be adsorbed to the proton acid doped PANI.Then the hydrophobic group of SDS outward the PANI,resulting a hydrophobic surface.PANI synthesized in the presence of SDS with bigger particle size has the lowest conductivity.The hydrophilic head group of cationic dispersant CTMAB is positively charged,the presence of CTMAB is not conductive to doping reaction of PANI with proton acid,and the charge transfer impedance of PANI is high.%采用乳液聚合的方式,分别选取十二烷基硫酸钠(SDS)、十六烷基三甲基溴化铵(CTMAB)、聚乙二醇(PEG)作为分散剂,制得了浸润度不同的聚苯胺(PANI).研究了不同类别分散剂对PANI性能的影响.采用扫描电镜(SEM)、X射线衍射(XRD)、水接触角(WCA)、傅里叶红外光谱(FT-IR)、紫外-可见光光谱(UV-Vis)、激光粒度仪等测试方法对PANI的结构与性能进行了分析,并通过循环伏安和交流阻抗实验研究了PANI的电化学性能.结果表明所有PANI样品均处于掺杂态,以PEG为分散剂的样品亲水性最佳,CTMAB次之,SDS最差.PEG为分散剂能够降低PANI的粒度,提高PANI的规整度进而增强其导电性能.阴离子分散剂SDS亲水端带负电,容易被质子掺杂的聚苯胺吸附,SDS的疏水端向外提供了PANI疏水性.SDS存在下合成的PANI粒度较大,电导率最低.阳离子型分散剂CTMAB因为其亲水端带正电不利于质子酸掺杂PANI,电荷转移阻抗较高.