单分散SiO_2微球的制备及疏水改性研究  

Preparation and Hydrophobic Modification of Monodisperse SiO_2 Nanospheres

作　　者：杨春 邵婷[2] 罗炫[2] 曹林洪[1,3] 蒋晓东[2] YANG Chun;SHAO Ting;LUO Xuan;CAO Lin-hong;JIANG Xiao-dong(School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China;Research Center of Laser Fusion, CAEP, Mianyang 621900, China;Joint Laboratory for Extreme Conditions Matter Properties, Southwest University of Science and Technology and Research Center of Laser of Laser Fusion, CAEP, Mianyang 621010, China)

机构地区：[1]西南科技大学材料科学与工程学院,绵阳621010 [2]中国工程物理研究院激光聚变研究中心,绵阳621900 [3]西南科技大学,中国工程物理研究院激光聚变研究中心极端条件物质特性联合实验室,绵阳621010

出　　处：《人工晶体学报》2017年第10期2030-2036,共7页Journal of Synthetic Crystals

基　　金：中国工程物理研究院科学技术发展项目基金(2015B0302071);西南科技大学重点科研平台专职科研创新团队建设基金(14tdjk04);龙山学术人才科研支持计划(17LZX505)

摘　　要：采用改进的凝胶-溶胶法制备了200~800 nm的单分散SiO_2微球,并通过真空冷冻干燥法得到不易团聚的单分散SiO_2粉体,采用乙醇超临界方法对制备的SiO_2微球进行疏水改性。通过扫描电镜和氮吸附-脱附分析仪对SiO_2微球的表面形貌、粒径以及孔径分布进行表征;用傅里叶红外变换测试和测量接触角对疏水改性的SiO_2微球进行分析。结果表明SiO_2微球粒径随二次加入TEOS体积增加呈先增大后减小。经过乙醇超临界处理,SiO_2微球表面成功接枝上了疏水烷基,微球尺寸越小,疏水性越好,其接触角高达149°,单次SiO_2微球处理量对结果无明显影响。采用本方法可以单次处理12 g以上的SiO_2微球,接触角均在140°左右,可充分满足实验室使用需求。经过真空冷冻技术和乙醇超临界技术得到疏水单分散SiO_2微球粉体,具有不易团聚及单分散性良好的优点,能够作为胶体晶体原料和三维有序材料(3-DOM)模板剂进行广泛应用。Monodispersed Si02nanospheres with diameters of200-800nm were prepared by improved Stober method where the tetraethyl silicate(TEOS),deionized water and ethanol were used as the raw materials.To avoid aggregation,the obtained wet nanospheres were dried by vacuum freeze drying technique afterward.The supercritical ethanol was used to modify the surfaces of the Si02nanospheres as hydrophobic.The morphologies and sizes of the nanosphers were investigated by the scanning electron microscope(SEM).And the size distribution of the pores was investigated by N2absorption and desorption measurement.The hydrophobic properties of the particles were characterized by measuring their contact angle to water.Fourier transform infrared spectroscopy(FTIR)was used to detect the chemical groups on the surfaces of the particles.The results show that the diameter of the Si02nanospheres initially increase and then decrease as the amount of the second addition of TEOS increase.The FTIR results show that by supercritical ethanol treatment,the surface of Si02nanospheres was grafted with alkyl groups successfully,which make the particles show hydrophobic properties.The smallest treated particles show the best hydrophobic performance,with their contact angle to water as high as149〇The amount of the treated particles has no obvious influence on the result.With this method,more than12g particles could be treated as hydrophobic(contact angle to water as high as140°)in one batch,which meet the laboratory-scale demand quite well.Since the hydrophobic Si02nanospheres prepared by us are easy to be dispersed and had the advantage of monodispersity,they would have a potential application in the field of3-DOM.

关 键 词：单分散Si02微球 疏水改性 真空冷冻干燥 乙醇超临界 

分 类 号：TG061[金属学及工艺]