摘要
埃洛石是一种卷曲的层状硅铝酸盐黏土,其储量丰富、价格低廉.埃洛石的内外表面分别由Al−OH八面体和Si−O四面体组成,它们在水中以相反的方式电离,导致埃洛石管腔内带正电荷,外表面带负电荷,因此可分别利用内外表面成分与电荷性质的不同对其进行疏水改性,用于药物的装载和缓释.同时,埃洛石具有纳米管状结构,可用来构造微−纳米分级结构,协同低表面能物质的修饰,增强界面疏水性能,用于高效自清洁和油水分离.本文在介绍埃洛石的疏水结构设计理论的基础上,综述了埃洛石纳米管(HNTs)的表面进行疏水改性所得到的复合材料在油水分离、疏水自清洁涂料以及药物的装载和释放方面的应用.
With the development of material design theories and synthesis technologies,clay-based composite materials have been controllably prepared and successfully applied in many fields,such as biomedicine,the automotive industry,petrochemical engineering,and wastewater treatment.To date,for the preparation of clay-based composite materials,the physical and chemical properties of clay must be fully considered,including the chemical composition,crystal structure,particle size,morphology,and surface charge.Halloysite,which has a tubular crystal structure,is a curly layered aluminosilicate clay with abundant reserves and a low price for constructing composite materials.The inner and outer surfaces of halloysite nanotubes are composed of Al−OH octahedrons and Si−O tetrahedrons,respectively,which ionize in opposite ways in water,resulting in opposite charges on the inner and outer surfaces.Therefore,the selective modification of halloysite can be achieved by chemical or electrostatic adsorption of the required chemical reagent.Additionally,the modified halloysite nanotubes can be used in catalysis and the loading and release of drug molecules.Moreover,because of its nanotube structure,the halloysite can be used to construct rough structures in micro-or nano-scale.By incorporation with low-surface-energy materials,the hydrophobic halloysite-based composite materials can be prepared for self-cleaning and oil-water separation.In this review,we introduced the rational design and preparation strategies of the hydrophobic halloysite-based composite materials.Then,we summarized the applications of these prepared composite materials in oil-water separation,hydrophobic self-cleaning coating,and the loading and sustained release of drug molecules.In addition,the related mechanisms and strategies for performance improvement were systematically discussed.Finally,the existing challenges and promising future directions in this research field were proposed.The halloysite-based composite materials have enhanced properties that are highly required,including enhanced mechanical and adhesive strength,excellent scratch and wear resistance,self-healing,and higher compatibility with living organisms.We believe fruitful promising results can be achieved in this field with more effort.
作者
曾丽
韵勤柏
鲁启鹏
曹文斌
ZENG Li;YUN Qin-bai;LU Qi-peng;CAO Wen-bin(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Department of Chemistry,City University of Hong Kong,Hong Kong 999077,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2021年第6期732-744,共13页
Chinese Journal of Engineering
基金
国家自然科学基金资助项目(52041201)
北京市科技新星资助项目(Z201100006820066)
中央高校基本科研业务费专项资金资助项目(FRF-DF-20-03)。
关键词
埃洛石
疏水
涂料
油水分离
纳米载体
halloysite
hydrophobic
coating
oil-water separation
nanometer carrier