掺入不同粒径Al_2O_3纳米颗粒的光致聚合物全息特性研究  

Study of holographic characteristics of photopolymers doped with different size Al_2O_3 nano-particles

作　　者：李潫玺 李春柳[1] 薛晓渝[1] 朱治广[1] 聂慧丽[1] 尉乔南[1] 黄明举[1] 

机构地区：[1]河南大学物理与电子学院,光学与光子技术研究所,河南开封475004

出　　处：《光电子．激光》2014年第5期913-919,共7页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(61177004)资助项目

摘　　要：在丙烯酰胺基光致聚合物材料中,分别掺入几种不同粒径的高分散性Al2O3纳米颗粒,用Ar+Kr+激光器647nm激光对其进行全息曝光,对其全息记录性能进行研究。结果表明,聚合物中掺入Al2O3纳米颗粒后,Al2O3纳米颗粒能够促进聚合物中光化反应的进行,同时用分散剂对Al2O3纳米颗粒的修饰,使Al2O3纳米颗粒的团簇效应降低,增加其单分散性。聚合物经曝光后,有效地形成由纳米颗粒与聚合物单体空间分布的折射率调制光栅,并且在聚合物中组成类"骨架"结构,有效地起到抑制材料的缩皱的作用,使材料的衍射效率和布拉格偏移等光学特性得到很大改善。此外,体系存在一个最优值,当掺入平均粒径约为10nm且同时控制浓度为1.02×10-3 mol/L的Al2O3纳米颗粒时,样品的衍射效率从52.6%提升到93.8%,缩皱率降低到0.8%,布拉格偏移降低到0.04°,极大地提高了材料的全息性能。Several different size Al_2O_3 nano-particles with high dispersion were doped into acrylamide based photopolymer materials, and the photopolymers were exposured with 647 nm Ar＋ Kr＋ laser to study the holographic properties. The results show that the incorporation of Al_2O_3 nano-particle leads to a significant improvement of the holographic characteristics, and the polymer photochemical reaction can be promoted. At the same time, through the surface modification of Al_2O_3 nano-particles with the dis- persant, the effect of clusters can be reduced and the dispersion increases. After the photopolymers were exposured, the permanent refractive index grating can be formed owing to a spatial distribution of the ef- fective refractive index with periodically distributed Al_2O_3 nano-particles and polymerized monomers during the holographic recording. There is a structure formed just like the skeleton in the polymer, which can inhibit the shrinkage and improve the optical properties of materials, such as the diffraction efficiency and the Bragg mismatch. Additionally, there exists the optimum concentration of Al_2O_3 nano-particles, the maximum diffraction efficiency of the sample can be raised from 52.6% to 93. 8%, the volume shrinkage can be depressed to 0. 8% while the the average size of Al_2O_3 nano-particles is about 10 nm and the concentration of Al_2O_3 is 1.02 × 10-3 mol/L.

关 键 词：光致聚合物 AL2O3 纳米颗粒 衍射效率 缩皱率 全息性能 

分 类 号：O438.1[机械工程—光学工程]