Wang Qin, Yu Heng, Zhang Zeyu, Zhao Yongliang, Wang Haitao
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.
Shanghai Dilato Materials Co., Ltd, Shanghai 200433, China.
J Colloid Interface Sci. 2020 Aug 1;573:62-70. doi: 10.1016/j.jcis.2020.03.118. Epub 2020 Mar 31.
Conventional strategies for strengthening silica aerogels through polymer modification always lead to a significant density increase and an obvious sacrifice of thermal insulation performance. In this work, we propose a facile one-pot method for the preparation of polymer-reinforced silica aerogels via polymerization of water-in-oil high internal phase emulsion (HIPE) templates.
Hyperbranched vinyl-modified polyethoxysiloxane (VPEOS) is used as both emulsion stabilizer and silica source. FT-IR spectra of VPEOS are recorded to confirm the successful incorporation of vinyl groups. The pore structure of polymer-functionalized silica aerogels is characterized by a scanning electron microscope (SEM), nitrogen adsorption-desorption and mercury intrusion porosimetry.
The Young's modulus is increased from 0.69 to 19.28 MPa, nearly 28 times that of unmodified silica aerogels. Moreover, the silica aerogels present a superhydrophobicity with a water contact angle of 152.4° and good thermal insulation. The superior performance properties of the polymer-reinforced silica aerogels over pure silica aerogels may guarantee their wide applications in energy and aerospace fields.
通过聚合物改性来强化二氧化硅气凝胶的传统策略总是会导致密度显著增加，并且明显牺牲隔热性能。在本研究中，我们提出了一种简便的一锅法，通过油包水型高内相乳液（HIPE）模板聚合来制备聚合物增强的二氧化硅气凝胶。
超支化乙烯基改性聚乙氧基硅氧烷（VPEOS）用作乳液稳定剂和二氧化硅源。记录VPEOS的傅里叶变换红外光谱（FT-IR）以确认乙烯基的成功引入。通过扫描电子显微镜（SEM）、氮气吸附-脱附和压汞法对聚合物功能化二氧化硅气凝胶的孔结构进行表征。
杨氏模量从0.69 MPa增加到19.28 MPa，几乎是未改性二氧化硅气凝胶的28倍。此外，二氧化硅气凝胶具有152.4°的水接触角，呈现超疏水性且隔热性能良好。聚合物增强的二氧化硅气凝胶相对于纯二氧化硅气凝胶的优异性能特性可能保证它们在能源和航空航天领域的广泛应用。
