Synthesis of fine monodispersed colloidal spheres and fabrication of high-quality colloidal crystals using the spheres

本研究的目的是制造近乎完美的密排胶体晶体。为了确定这种制备方法，我们进行了以下三个实验：1)合成高度单分散的胶体球，2)原位观察自组装过程并评估所制备的胶体晶体的结晶度，3)对激光退火修复缺陷的可能性进行了基础研究。结果，我们发现即使我们使用单分散度小于1%的高单分散聚苯乙烯（PS）球也很难获得高质量的胶体晶体，因为水的干燥使球缩小。然而，通过这项研究获得了一些有用的发现。高度单分散胶体球的合成(1)单分散度小于1%的评价需要在透射显微镜图像中读取合成球的直径。(2)在250 ~ 500 nm范围内合成了单分散性小于1%的PS微球。(3)合成了玻璃化转变温度大于120℃、单分散度小于3%的交联PS球。(1)用共焦激光显微镜对胶体晶体在流体细胞中的生长过程进行了原位观察，发现了生长方式和生长速率的变化。(2)建立了一种新的胶体晶体三维结构分析方法，揭示了PS球组成的胶体晶体的各向异性。(3)揭示了用对流法制备的晶体中经常观察到的条纹结构是由重复双胞胎引起的。激光退火的基础研究：对球间含水的密排胶体晶体的激光退火熔化和再结晶的观察表明，激光退火有可能恢复缺陷和引入故意缺陷。

The purpose of this study is to fabricate almost perfect close-packed colloidal crystals. To establish the fabrication, we tried the following three experiments : 1) synthesis of highly monodispersed colloidal spheres, 2) in situ observation of self-assembling process and evaluation of crystallinity in the fabricated colloidal crystals, and 3) fundamental investigations for possibilities of recovering defects by laser annealing.As a result, we found that is was difficult to obtain extremely high-quality colloidal crystals even though we used highly monodiperesed polystyrene(PS) spheres with the monodispersity less than 1%, because drying of water shrank the spheres. However, several useful findings were obtained through this study.1. Synthesis of highly-monodispersed colloidal spheres(1) It was necessary for the evaluation of monodispersity less than 1% to read diameters of the synthesized spheres in transmission microscope images.(2) PS spheres with monodispersity less than 1% were synthesized in the diameter range between 250 and 500 nm.(3) Cross-linked PS spheres with the glass transition temperature more than 120 C and the monodipersity less than 3% were synthesized.2. Fabrication of colloidal crystals(1) The changes of the growth manner in the growth rate was found by in situ observation of the growth process of colloidal crystals in a fluidic cell with a conforcal laser microscope.(2) We established a new method for 3D structure analysis of colloidal crystals and revealed the anisotropy of the colloidal crystals composed of PS spheres.(3) The striped structure often observed in the crystals prepared by a convective flow method was revealed to be due to repeated twins.3. Fundamental investigations of laser annealingObservations of melting and recrystalization by laser annealing in the close-packed colloidal crystals containing water between the spheres indicated a possibility that laser annealing will recover defects and introduce intentional defects.