物理化学学报 >> 2013, Vol. 29 >> Issue (03): 646-652.doi: 10.3866/PKU.WHXB201212252

材料物理化学 上一篇    下一篇

溶胶-凝胶伴随相分离制备SiO2多孔块体

郭兴忠1, 李文彦1, 朱阳2, 中西和樹2, 金森主祥2, 杨辉1   

  1. 1 浙江大学材料科学与工程学系, 杭州 310027;
    2 日本京都大学大学院理学研究科, 京都, 606-8502
  • 收稿日期:2012-09-15 修回日期:2012-12-24 发布日期:2013-02-25
  • 通讯作者: 杨辉 E-mail:yanghui@zju.edu.cn
  • 基金资助:

    浙江省重点创新团队项目(2009R50010)资助

Macroporous SiO2 Monoliths Prepared via Sol-Gel Process Accompanied by Phase Separation

GUO Xing-Zhong1, LI Wen-Yan1, ZHU Yang2, NAKANISHI Kazuki2, KANAMORI Kazuyoshi2, YANG Hui1   

  1. 1 Department of Materials Science and Engineering of Zhejiang University, Hangzhou 310027, P. R. China;
    2 Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
  • Received:2012-09-15 Revised:2012-12-24 Published:2013-02-25
  • Supported by:

    The project was supported by the Key Innovation Team Project of Zhejiang Province, China (2009R50010).

摘要:

以正硅酸甲酯(TMOS)为前驱体, 0.01 mol·L-1盐酸(HCl)为催化剂, 环氧丙烷(PO)为凝胶促进剂, 粘均分子量(Mv)为10000的聚氧化乙烯(PEO)为相分离诱导剂, 采用溶胶-凝胶伴随相分离制备SiO2多孔块体材料,利用差热分析(DTA)、傅里叶变换红外(FT-IR)光谱、扫描电镜(SEM)、X射线衍射(XRD)、汞压、N2吸附/脱附等测试技术对所制得的SiO2多孔块体进行了表征, 探讨了环氧化物调控溶胶-凝胶以及PEO诱导相分离机理. 结果表明, 加入PEO能诱导SiO2凝胶发生相分离, 当PEO/TMOS摩尔比为0.0018时, 可以获得共连续多孔结构的SiO2块体材料, 其大孔孔径分布在1-3 μm之间, 比表面积达719 m2·g-1, 孔体积为0.48 m3·g-1. 环氧丙烷因其环氧原子的强亲核性和不可逆的开环反应, 促进溶胶-凝胶转换, 同时借助吸附在SiO2低聚物上的PEO诱导SiO2凝胶相分离, 从而制备共连续大孔及骨架结构的多孔块体.

关键词: 多孔块体, SiO2, 溶胶-凝胶, 相分离, 环氧丙烷, 聚氧化乙烯

Abstract:

Macroporous SiO2 monoliths were prepared via a sol-gel process accompanied by phase separation using a tetramethoxysilane (TMOS) precursor, 0.01 mol·L-1 HCl catalyst, propylene oxide (PO) gelation agent, and poly(ethylene oxide) (PEO, viscosity-averaged molecular weight (Mv): 10000) phase separation inducer. Monoliths were characterized by differential thermal analysis/thermogravimetry (DTA/ TG), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, and nitrogen adsorption/desorption analysis (BET). The mechanism of the epoxide-mediated sol-gel reaction and PEO induced phase separation was discussed. The addition of PEO induced phase separation, and monolithic SiO2 with a cocontinuous macroporous skeletal structure was obtained at PEO/TMOS molar ratio of 0.0018. Monoliths had a narrow pore size distribution of 1-3 μm, surface area as high as 719 m2·g-1 and pore volume of 0.48 m3·g-1. This sol-gel transition is mediated by PO because of its strong nucleophilic properties and irreversible ring-opening reaction. Simultaneous phase separation is induced by PEO adsorbed on the SiO2 oligomers.

Key words: Porous monolith, Silica, Sol-gel, Phase separation, Propylene oxide, Poly(ethylene oxide)

MSC2000: 

  • O647