纳米二氧化硅粉体的表面改性研究进展

简介了纳米二氧化硅的表面改性方法；重点介绍了国内外纳米二氧化硅的表面改性方法及其对材料性能的影响；指出了纳米二氧化硅在聚合物基复合材料中的应用；展望了其发展前景。     

纳米二氧化硅表面改性研究进展

综述了纳米二氧化硅表面改性的研究进展及其在橡胶、涂料、塑料及生物医药等领域的应用,重点介绍了偶联剂法、醇酯法、聚合物接枝法和原位法等化学改性方法,展望了纳米二氧化硅改性的发展方向和应用前景。     

纳米二氧化硅改性聚丙烯复合材料研究进展

介绍了近年来纳米二氧化硅改性聚丙烯复合材料的研究进展,综述了纳米二氧化硅粒子表面处理和添加增容剂改性的主要方法,阐述了纳米粒子与聚合物相容性的提高对复合材料各项性能的改善作用,并讨论了不同纳米二氧化硅颗粒结构对复合材料性能的影响,最后展望了其在改善聚合物渗透性、阻燃性、导电性等方面的发展前景。     

纳米二氧化硅微球表面接枝嵌段聚合物的制备及其在丙烯酸结构胶体系中的性能研究

以二氧化硅微球为模板,将其表面修饰上活性官能团。通过表面引发可控/“活性”自由基聚合,连续引发苯乙烯和甲基丙烯酸2-羟基乙酯聚合,得到表面接枝嵌段聚合物的纳米二氧化硅微球,并对其进行表征。将表面修饰的二氧化硅微球用于丙烯酸结构胶体系,并和未修饰二氧化硅微球的体系进行对比。研究结果表明：通过结构表征证明了目标产物合成成功;将表面修饰的二氧化硅微球用于丙烯酸结构胶体系,聚合物改性的纳米二氧化硅在拉伸强度、断裂伸长率和剪切强度等性能的表现均优于未改性的纳米二氧化硅;纳米二氧化硅在固化体系中具有增强增韧的作用,表面接枝聚合物改性后,其性能表现更优。     

纳米二氧化硅表面改性及其补强天然胶乳研究

简述了纳米二氧化硅的表面结构、表面改性机理及方法。介绍国内外对纳米二氧化硅表面化学改性及纳米二氧化硅改性天然橡胶复合材料的制备工艺进行详述,最后对纳米二氧化硅改性天然胶乳存在的问题和发展方向进行了展望。     

纳米二氧化硅的分散及其在涂料中的应用

纳米二氧化硅粒子的分散方法有物理法和化学法,主要对其化学分散方法进行了介绍.列举了常见的二氧化硅化学改性方法,其改性剂主要有醇、有机硅化合物、聚合物、硅烷偶联剂.分析了表面活性剂添加量对二氧化硅分散的影响.对纳米二氧化硅在涂料和聚合材料中的应用进行了介绍.提出了纳米二氧化硅分散问题的重要性与紧迫性。     

纳米二氧化硅表面改性及其补强天然胶乳研究

简述了纳米二氧化硅的表面结构、表面改性机理及方法,介绍国内外对纳米二氧化聩表面化学改性及纳米二氧化硅改性天然橡胶复合材料的制备工艺进行详述,最后对纳米二氧化硅改性天然胶乳存在的问题和发展方向进行了展望。     

鞣酸改性纳米二氧化硅对UV固化涂料性能的影响

通过在纳米二氧化硅-乙醇悬浮液中加入一定量鞣酸的方法,在纳米二氧化硅表面引入羟基等活性基团对纳米二氧化硅进行表面改性,并用SEM、FTIR和TG等手段对鞣酸表面改性纳米二氧化硅的改性机理进行研究。利用交流阻抗图谱(EIS)研究包覆后二氧化硅对UV固化涂料的防腐蚀性能。结果表明:鞣酸是以化学键合的方式接枝到纳米二氧化硅表面,改性后的纳米二氧化硅分散良好,鞣酸改性纳米SiO2能极大提高UV固化涂层防腐蚀效果。     

聚合物/二氧化硅复合材料分散方法研究进展

介绍了聚合物/二氧化硅(SiO2)复合材料的制备方法,以及SiO2的表面改性及其在聚合物基体中分散方法的研究进展。讨论了SiO2的表面改性方法对复合材料性能的影响,并展望了聚合物/SiO2复合材料的发展趋势和应用前景。     

纳米粒子及其在复合材料改性中的应用

介绍了纳米粒子的一些优异特性和表面改性的方法，并详细阐述了纳米粒子充聚合物聚合材料的主要制备方法，研究进展及其良好性能。     

纳米二氧化硅的结构及表面改性对橡胶复合材料性能影响的研究进展

分析了纳米SiO_2结构及表面改性对其填充橡胶复合材料性能的影响,对比了不同表面改性方法对SiO_2增强效果的影响,指出基于良好分散性的适度结构化和高效功能化表面改性是提高SiO_2增强橡胶复合材料性能的重要因素.简要介绍了纳米SiO_2在橡胶复合材料中的应用研究现状.     

Synthesis and characterization of nanosilica/polyacrylate composite latex

The nanosilica/polyacrylate organic–inorganic composite latex was synthesized by in‐situ emulsion polymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of silica nanoparticles, which were modified by silane coupling agent. The surface properties and dispersibility of silica nanoparticles modification, chemical structure, Zeta potential, diameter distribution of the composite latex prepared, surface roughness, and thermal stability of the hybrid film formed by the composite latex were investigated by fourier transform infrared spectrometer (FTIR), transmission electron microscopy (TEM), Zeta meter, ZetaPlus apparatus (dynamic light scattering method), atomic force microscopy (AFM), and thermogravimetric analysis (TGA), respectively. After modification with silane coupling agent, silane was grafted onto the surface of silica nanoparticles to form the organic layers, which was able to efficiently prevent the silica nanoparticles from aggregating to individually homogeneous disperse in the in‐situ emulsion polymerization system and improve the compatibility of silica nanoparticles with the acrylate monomers. The nanosilica/polyacrylate organic–inorganic composite latex prepared had the properties of silica nanoparticles and pure polyacrylate latex but was not simply a combination. Strong chemical bonding tethered the silica and acrylate chains to form the core/shell structural composite latex. Consequently, the hybrid film formed by nanosilica/polyacrylate composite latex exhibited a smooth surface and better thermal properties than the pure polyacrylate film. POLYM. COMPOS. 27:282–288, 2006. © 2006 Society of Plastics Engineers     

Morphology of polypropylene/silica nano‐ and microcomposites

The aim of this study was to compare the effects of different silica grades on the structure and morphology of isotactic polypropylene (iPP)/silica composites to better understand their structure–property relationships. Isotactic polypropylene composites with 2, 4, 6, 8 vol % of added silica fillers differing in particle size (micro‐ vs. nanosilica) and surface modification (untreated vs. treated surface) were prepared by nonisothermal compression molding and characterized by different methods. The addition of all silica fillers grades to the iPP matrix significantly influenced the spherulitic morphology, while phase characteristics of the iPP matrix seemed to be unaffected. Surface modification of silica fillers exhibited stronger effects on spherulite size than size of silica particles. Nonpolar silica particles, more miscible or compatible with iPP chains than polar silica particles, enabled better spherulitic growth. The spherulite sizes tended to reach equal values at 8 vol % of added silicas showing that spherulite size became independent of filler concentration and surface modification above optimum filler concentration. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation and properties of polymerizable silica hybrid nanoparticles with tertiary amine structure

To increase the photopolymerization rate and improve the properties of UV coatings, polymerizable silica hybrid nanoparticles with tertiary amine structure were prepared. Organic compound with isocyanate group was first grafted onto the surface of nanosilica by reaction of nanosilica with isophorone diisocyanate, then the nanosilica bearing isocyanate group reacted with N,N-di(3-propionic acid, 1,4,7-trimethyl-3,6-dioxaoctane-8-yl acrylate, ester) ethanolamine synthesized from tripropylene glycol diacrylate and ethanolamine. The preparation was characterized by ¹H nuclear magnetic resonance (NMR) and Fourier transform infrared spectrometry (FT-IR). Thermogravimetric analysis (TGA) showed that the organic compounds grafted onto the silica decomposed from 256 °C to 650 °C and the grafting percentage based on nanosilica was 105%. The morphology analysis of nanosilica and modified silica by field-emission scanning electron microscopy (FE-SEM) indicated that the silica kept nanosized scale after modification, while the nanosilica dispersion was improved and formation of agglomerates unlikely. Determination of viscosities of coatings with modified nanosilica, it was found that viscosities of the coatings decreased in comparison with the viscosities of coatings with unmodified nanosilica. Compared with pure organic coating, the photopolymerization rate of coatings were faster when modified nanosilica was used from 1 wt% to 5 wt%, but slower when the loadings of modified nanosilica was 7 wt% because co-initiating effects of tertiary amine compound grafted on nanosilica counterbalanced the effects of UV scattering by silica on photopolymerization rate. The hardness and abrasive resistance of cured films also increased and improvement degree was different when the various amounts of modified nanosilica were used.     

纳米二氧化硅复合材料的研究进展

介绍了纳米 Si O2 的优异性能、表面改性方法和制备方法 ,论述了纳米 Si O2 复合材料的研究进展。     

纳米SiO_2/聚丙烯酸酯组装杂化乳液的合成及表征

通过乳液聚合法成功合成了纳米SiO2/聚丙烯酸酯杂化乳液。首先将纳米SiO2经过表面官能团化处理,使其表面含有活性官能团,然后经过乳液聚合使丙烯酸酯单体在纳米SiO2表面引发聚合,合成了具有核壳结构的纳米杂化乳液。采用透射电子显微镜(TEM)对乳液的微观结构进行了表征,并对胶膜进行了机械力学性能测试和表面润湿性能测试。结果表明纳米SiO2的表面官能团化处理改善了纳米粒子在乳液中的稳定性,当纳米SiO2质量分数为0 2%时,杂化乳液胶膜的拉伸强度和断裂伸长率同时达到最大值。其表面润湿性与SiO2质量分数有关,SiO2质量分数为0 5%时其杂化乳胶膜的接触角最大,耐水性最好。     

Synthesis of new superhydrophobic nanosilica and investigation of their performance in reinforcement of polysiloxane

We reported a new facile method to synthesize superhydrophobic nanosilica using glycidoxypropyltrimethoxysilane and dodecylamine as treatment agents. Also, we systemically investigate their performance in reinforcement of poly(dimethylsiloxane) (PDMS) rubber. Fourier transform infrared spectrum, contact angle (CA) and thermogravimetric analysis (TGA) measurements were used to characterize the modified nanosilica. Results show that the inherent hydrophilicity of parent nanosilica surface can be greatly altered through this modification method. The CA of as‐prepared superhydrophobic nanosilica can reach 160.2°. The properties of as‐prepared modified nanosilica‐filled PDMS composites were systemically investigated by dynamic rheological test, scanning electron microscopy, TGA, dynamic mechanical analysis. These as‐prepared superhydrophobic nanosilica exhibit uniform dispersion in the PDMS matrix, and their composites also show good mechanical properties and distinct advantage on thermal stability compared with those of the pure silica‐filled PDMS composites. Also described is the probable mechanism for the reinforcement of as‐prepared superhydrophobic nanosilica‐filled PDMS. POLYM. COMPOS., 31:1628–1636, 2010. © 2009 Society of Plastics Engineers     

可分散性纳米SiO2对甲基乙烯基硅橡胶结构与性能的影响

考察了原位改性法制备的可分散性DNS-2型纳米SiO2对甲基乙烯基硅橡胶(MVQ)结构与性能的影响,并与气相法白炭黑填充MVQ进行了比较。结果表明,DNS-2-1型、DNS-2-2型和DNS-2-3型纳米SiO2为类球形颗粒,其表面改性的有机物质量分数分别为6.0%,3.9%,3.1%;DNS-2型纳米SiO2填充MVQ的加工性能及力学性能均优于气相法白炭黑填充MVQ;填充DNS-2型纳米SiO2后,MVQ的结晶温度降低,熔融吸热减小,在低温下不易硬化;DNS-2型纳米SiO2与MVQ的相容性及其在硅橡胶中的分散性优于气相法白炭黑。