摘要
利用静电自组装方法在石英玻璃表面交替沉积聚二烯丙基二甲基氯化铵(PDDA)和聚偏氟乙烯(PVDF)超薄膜,制得PDDA/PVDF铁电复合超薄膜.通过石英晶体微天平实时监测超薄膜的沉积,研究了超薄膜的表面形貌、结构及电性能.结果表明,自组装每层PVDF超薄膜的厚度为7.5 nm;PDDA/PVDF铁电复合超薄膜的表面平整、均匀,其中C1s的光电子能谱与极化处理后充负电荷的PVDF铁电聚合物一致,但F1s由于溶解再组装过程而降低了0.3 eV;静电自组装材料纳米级的薄膜厚度和聚合物的络合作用导致了铁电复合超薄膜的非晶结构和高的表面电阻率.
Poly（diallyldimethyl ammonium chloride）（PDDA） and ferroelectric poly（vinylidene fluoride）（PVDF） composite ultrathin films on quartz glass prepared by electrostatic layer-by-layer self-assembly（SA） have been investigated.Physical measurements of deposited mass for each layer were performed with quartz crystal microbalance（QCM）,while the morphology of ultrathin films was observed by atomic force microscope（AFM）.And the element and composite structure of PDDA/PVDF were determined by X-ray photoelectron spectroscopy（XPS） and gracing incident X-ray diffraction（XRD）,respectively.The surface resistivity and electric hysteresis loop of ferroelectric ultrathin films have been studied also.The results showed that the thickness of each layer for self-assembled PVDF ultrathin films on QCM substrate was about 7.5 nm,and the morphology of composite ultrathin films was uniform.The binding energy of F1s in composite ultrathin films was decreased 0.3 eV comparing with the poled PVDF films,which was caused by the distribution of negative charges as the re-dissolution of polymer.In addition,the surface resistivity was improved to over 1017 Ω·cm for orderly self-assembly,and the remanent polarization was about 0.1 μC/cm^2 for non-ferroelectric PVDF in PDDA/PVDF ultrathin films.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2009年第11期1091-1095,共5页
Acta Polymerica Sinica
基金
国家高技术研究发展计划(863计划
项目号2004AA302080)
国家自然科学基金项目(基金号20474017)资助项目
关键词
静电自组装
铁电聚合物
超薄膜
Electrostatic self assembly
Ferroelectric polymer
Ultrathin film
