聚酰亚胺/SiO_2杂化材料的溶胶-凝胶法合成、表征及电光性能(英文)

Synthesis,Characterization and Electro-optic Properties of Polyimide/Silica Hybrid via Sol-Gel Technique

采用溶胶-凝胶技术,以4,4’-(六氟异丙基)-苯二酸酐(6FDA)、5,5’-(六氟异丙基)-二-(2-氨基苯酚)(6FHP)、非线性生色分子4-(N-2-羟乙基-N-甲基氨)-4’-[(6-硝基苯并噻唑-2-取代)二氮烯基偶氮苯(HNBDA)、偶联剂γ-氨丙基三乙氧基硅烷(APTES)和正硅酸乙酯(TEOS)水解液合成了系列的聚酰亚胺/SiO2杂化材料,其中TEOS的含量为0～22.5%。采用红外、热分析、扫描电镜、透射电镜和X射线衍射等进行表征。它们的玻璃化转变温度和热分解温度分别为216～366℃和321～438℃,表明具有较好的热稳定性。测定极化后材料832nm处的电光系数γ33为21～35pm/V,且电光系数保持其初始值的85%以上(100h),结果表明杂化材料在光器件上具有潜在的应用。

A series of the polyimide-silica NLO hybrid materials were synthesized from 4,4＇-（Hexafluoroisopropylidene） -diphthalic Anhydride （6FDA）, 2,2-Bis（3-amino-4-hydroxyphenyl） hexafluoropropane （6FHP） , nonlinear optical （NLO） molecule 4-（N-2-Hydroxyethyl-N-methylamino）-4＇-[（6-nitroben-zothiazol-2-yl）diazenyl]azobenzene （HNBDA）, coupling agent APTES and hydrolysate of TEOS via sol-gel process. The TEOS content in the hybrid films was varied from 0 to 22.5wt%. The prepared polyimide/silica hybrids were characterized by IR, thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, Transmission Electron Microscope（TEM）, X-ray diffraction（XRD） etc. The glass transition temperature （Tg） and the decomposition temperature （Td） were in the range 216-366 ℃ and 321-438℃ respectively for materials. These results show that these hybrid materials had an excellent thermal stability. The electro-optic coefficients （γ33） at the wavelength of 832 nm for polymer thin films poled were in the range of 21-35 pm/V and the values remained well （retained 〉85% for more than 100 h）. The experimental results suggest that the hybrid thin films have potential applications as passive films for optical devices.