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采用2,2,6,6-四甲基-1-哌啶氧化物(TEMPO)的溴盐对化学共沉淀法制备的Fe3O4纳米粒子进行表面修饰,以该粒子为过氧引发剂,苯乙烯(St)、马来酸酐(MA)为单体,采用"活性"/可控自由基聚合技术在粒子表面原位引发聚合,制备了聚(苯乙烯-马来酸酐)/Fe3O4纳米杂化材料,并对纳米Fe3O4及杂化材料进行了FT-IR、XRD、TGA、TEM和GPC表征。结果表明,所制备的纳米杂化材料的平均粒径约为70 nm,磁性粒子表面的聚合物分子链随着聚合时间的增长而增长。振动样品磁强计测试结果显示,在室温、外加磁场下,该纳米杂化材料呈现超顺磁性,饱和磁化强度随着包覆聚合物量的增加而降低。 相似文献
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聚酰亚胺-二氧化硅杂化膜的制备及表征 总被引:21,自引:0,他引:21
采用溶胶-凝胶法制备了两类具有不同二氧化硅含量的聚酰亚胺-二氧化硅(PI-SiO2)杂化膜,并用SEM,IR,TG-DTA,氮吸附和气体渗透性能测试等手段对该膜材料的表面形貌、结构、热性能、孔径分布和气体渗透性能进行了表征.结果表明,PI-SiO2膜材料中SiO2粒子的分散良好,与有机相之间存在着分相和键联;膜材料的玻璃化温度θg均随SiO2含量的增加而升高.相比之下,在酸性条件下制备的T系列杂化膜比在碱性条件下合成的S系列杂化膜对θg的影响更大一些;杂化膜具有较好的气体渗透性能和亲水性能,其H2O/N2和H2O/CH4的分离系数远大于努森扩散的理论值. 相似文献
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聚合物-纳米晶杂化材料因结合了有机和无机材料的优点而逐渐地受到了人们普遍的关注,聚合物为纳米晶的形成与生长提供了优良的环境,纳米晶的引入同样也增加和强化了聚合物的功能特性.如聚硫代氨基甲酸酯与TiO2杂化的高折射率薄膜,该薄膜不仅保持了原有的性能,而且有较高的折射率.此外,还有许多不同纳米粒子与不同聚合物的杂化体系.如... 相似文献
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SiO2/聚合物核壳型杂化粒子及其空心结构以其独特的形貌在药物控制释放、催化剂载体、生物医药等领域应用前景广阔,引起了人们的广泛关注。本文着重从乳液聚合法、仿生矿化法等制备方法角度阐述了SiO2/聚合物核壳型杂化粒子及其空心结构的研究进展。乳液聚合制备SiO2/聚合物核壳型杂化粒子简单易行,一般需要预先合成SiO2纳米粒子,其合成过程通常需要一些非理想的条件,如高温高压、极端pH、昂贵或有毒的有机试剂等,而且预先合成的SiO2粒子无法与聚合物实现100%匹配,即总有纯的聚合物粒子存在。相比之下,原位仿生矿化法制备SiO2杂化粒子不仅在环境条件下可进行,而且能够精确控制其纳米尺度的形态及分级有序结构。目前对材料科学家来讲,要使人工合成SiO2/聚合物杂化粒子实现像自然生物硅那样优异的性能,仍然是很大的挑战。 相似文献
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近年来材料科学与技术的不断发展,对光学材料提出了高性能化和多功能化的需求,为此,研究者们结合传统有机聚合物光学材料和无机光学材料的优势,提出了备受关注的聚合物纳米粒子杂化的策略.本文首先概述了针对杂化材料透光性进行控制的杂化方法,指出杂化方法的选择很大程度上与材料性质尤其是纳米相的性质相关,而杂化方法的目的则在于实现纳米杂化材料的透光性控制,纳米杂化光功能材料实现功能的前提即为透光性.随后,分别介绍了聚合物纳米杂化策略在高折射率材料与发光材料中的应用.对于高折射率材料,总结了提升材料折射率的不同策略.对于发光材料,总结了基于聚合物相和纳米相之间不同的相互作用而采用各种杂化方式以及相关的性能提升.接下来,讨论了聚合物纳米杂化光功能材料在光学和机械、热学、表面性能方面的调控手段和性能提升的策略.最后,提出了下一代光学杂化材料所面临的困难与挑战,以进一步推动这一领域的发展. 相似文献
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The organic/inorganic hybrid nanomaterials containing silica nanoparticles are synthesized by sol-gel crosslinking process. The tetraethoxysilane (TEOS) and γ-aminopropyltriethoxylsilane as coupling agents are used as a precursor. The 2,4,6-tri [(2-epihydrin-3-bimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-EBAC) as crosslinking agent is used to form covalent bonds among the inorganic nanoparticles. The chemical and morphological structures of the organic/inorganic hybrid are characterized with FTIR spectra, 29Si-NMR, x-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and atomic force microscope (AFM). The results show that the organic/inorganic hybrid forms covalent bond between the inorganic nanoparticle and Tri-EBAC. The network organic/inorganic hybrid can form good film with even nanometer particles. The network organic/inorganic hybrids nanomaterial not only exhibits the thermal properties of inorganic compounds, but also exhibits the thermal properties of organic polymer. 相似文献
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聚醚型氨酯酰亚胺/二氧化硅杂化材料的合成与性能研究 总被引:4,自引:0,他引:4
利用Sol Gel共聚合反应制备出聚醚型氨酯酰亚胺 (PUI) /二氧化硅 (SiO2 )杂化材料 .利用NMR、FTIR、TG、DSC及SEM等测试手段对性能进行了基本表征 .FTIR研究结果发现在 10 0℃下能同时完成有机相PUI的亚胺化和无机相SiO2 凝胶网络的Sol Gel转变 .TG及SEM发现SiO2 含量为 9wt%时SiO2 聚集相粒径在 0 2~1 0 μm之间 ,耐热性明显提高并达到最佳 ;发现SiO2 含量的增加其颗粒粒径不断增大 ,并不断聚集成大粒径SiO2 相 ,有机和无机相分离明显 .DSC研究显示 ,SiO2 相的引入 ,对杂化材料聚醚软段富集相的Tg 不产生明显影响 . 相似文献
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Chin‐Lung Chiang Chen‐Chi M. Ma Dai‐Lin Wu Hsu‐Chiang Kuan 《Journal of polymer science. Part A, Polymer chemistry》2003,41(7):905-913
This article describes the preparation of novolac‐type phenolic resin/silica hybrid organic–inorganic nanocomposite, with a sol–gel process. The coupling agent was used to improve the interface between the organic and inorganic phases. The effect of the structure of the nanocomposite on its physical and chemical properties is discussed. The coupling agent reacts with the resin to form covalent bonds. The structure of the modified hybrid nanocomposites was identified with a Fourier transform infrared spectroscope. The silica network was characterized by nuclear magnetic resonance imaging (29Si NMR). Results revealed that Q4 (tetrasubstituted) and T3 (trisubstituted) are the dominant microstructures. The size of the silica in the phenolic resin was characterized with a scanning electron microscope. The size of the particles of inorganic silica in the modified system was less than 100 nm. The nanocomposite exhibited good transparency. Moreover, the thermal and mechanical properties exhibited significant improvement. The modified hybrid composite exhibited favorable thermal properties. The temperature at which a weight loss of 5% occurred increased from 281 to 350 °C. The flexural strength increased by 6–30%. The limiting oxygen index of the nanocomposite reached 37, and the Underwriters Laboratory test was 94V‐0. Consequently, these materials possess excellent flame‐retardant properties. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 905–913, 2003 相似文献
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Vikas Mittal 《Colloid and polymer science》2010,288(6):621-630
Hybrid organic–inorganic latex particles are synthesized to combine the beneficial properties of the constituents which thus
lead to synergistic improvement in the properties. The properties of hybrid particles are dependent on the successful hybridization
process, thus controlling or tuning of such processes by effective characterization is immensely important. Analytical ultracentrifugation
provides these characterization possibilities owing to its high statistical capability and ability to characterize multiple
parameters. The use of different detection methodologies can help in generating valuable information on the overall size and
density distributions of the particles. Apart from that, it is also possible to quantify the presence of any free polymer
and inorganic particles in the hybrid latex which would affect the properties of hybrid latexes. By following the densities
of the pure and hybrid particles, it is also possible to quantify the amounts of the constituent phases in the hybrid particles.
The density gradients generated in preparative ultracentrifugation also provide additional possibilities for the characterization
of the hybrid particles which have densities higher than the measurable range in the analytical ultracentrifuge. Evolution
of hybrid particles can also be studied as a function of time. It also provides advantage of separation of the various fractions
for further characterization. 相似文献
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Oliver Mahony Sheng Yue Claudia Turdean-Ionescu John V. Hanna Mark E. Smith Peter D. Lee Julian R. Jones 《Journal of Sol-Gel Science and Technology》2014,69(2):288-298
Owing to their diverse range of highly tailorable material properties, inorganic/organic hybrids have the potential to meet the needs of biodegradable porous scaffolds across a range of tissue engineering applications. One such hybrid platform, the silica–gelatin sol–gel system, was examined and developed in this study. These hybrid scaffolds exhibit covalently linked interpenetrating networks of organic and inorganic components, which allows for independent control over their mechanical and degradation properties. A combination of the sol–gel foaming process and freeze drying was used to create an interconnected pore network. The synthesis and processing of the scaffolds has many variables that affect their structure and properties. The focus of this study was to develop a matrix tool that shows the inter-relationship between process variables by correlating the key hybrid material properties with the synthesis parameters that govern them. This was achieved by investigating the effect of the organic (gelatin) molecular weight and collating previously reported data. Control of molecular weight of the polymer is as an avenue that allows the modification of hybrid material properties without changing the surface chemistry of the material, which is a factor that governs the cell and tissue interaction with the scaffold. This presents a significant step forward in understanding the complete potential of the silica–gelatin hybrid system as a medical device. 相似文献
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溶胶-凝胶法制备二氧化钛纳米粒子及在光固化体系中的稳定分散 总被引:2,自引:0,他引:2
选用3种不同的稳定剂,乙酰丙酮(acac),异丙氧基三(焦磷酸二辛酯)钛(TTPO)和可聚合有机磷酸酯(MAP),采用钛酸四正丁酯(TBT)通过溶胶-凝胶法合成了一系列二氧化钛溶胶,并与树脂/单体相混合,制备成有机-无机杂化光固化涂料.利用FT-IR监测了TBT水解缩合形成溶胶的过程及杂化体系的光聚合过程.杂化固化膜SEM结果显示,在合成溶胶过程中添加不同的稳定剂对杂化固化膜中无机粒子粒径尺寸等形态有显著影响,其中使用TTPO作为稳定剂得到的无机粒子分散最均匀,粒径最小,约20 nm.物理性能测试表明光固化杂化膜在硬度和柔韧性方面都有明显的改善. 相似文献
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Jinliang Liu 《Journal of organometallic chemistry》2010,695(4):580-587
This work focuses on the construction of a series of chemically bonded rare-earth/inorganic/organic hybrid materials (TCH-Si-Ln, TCH-Si-Ln-Phen and TCH-Si-Ln-Bipy: Phen = 1,10-phenanthroline, Bipy = 2,2′-bipyridyl) using TCH-Si as an organic bridge molecule that can both coordinate to rare-earth ions (Eu3+ and Tb3+) and form an inorganic Si-O-Si network with tetraethoxysilane (TEOS) after cohydrolysis and copolycondensation through a sol-gel process. All of these hybrid materials exhibit homogeneous microstructures and morphologies, suggesting the occurrence of self-assembly of the inorganic network and organic chain. Measurements of the photoluminescent properties of these materials show that the ternary europium systems present stronger luminescent intensities than the binary hybrids, indicating that the introduction of the second ligands can sensitize the luminescence emission of the europium hybrid systems. However, in the terbium systems, this phenomenon was not observed. 相似文献
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Liang-Liang Liu Qin Wang Dan Xia Ting-Ting Shen Ming-Hui Yu Wei-Sheng Liu Yu Tang 《中国化学快报》2013,24(2):93-95
Optical hybrid materials based on inorganic hosts and organic sensitizer guests hold promise for a virtually unlimited number of applications.In particular,the interaction and the combination of the properties of a defined inorganic matrix and a specific sensitizer could lead to synergistic effects in luminescence enhancing and tuning.The current article focuses on the intercalation assembly of optical hybrid materials based on the layered terbium hydroxide(LTbH) hosts and organic divalent carboxylic sensitizer anion guests by a hydrothermal process.The studies on the interactions between hosts and guests indicate that the type and arrangement of organic guests in the layer spacing of the LTbH hosts can make a difference in the luminescence of the hybrid inorganic-organic materials. 相似文献
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溶胶-凝胶法合成聚甲基丙烯酸甲酯/二氧化钛杂化聚合物材料 总被引:7,自引:0,他引:7
由共聚合在PMMA聚合物链段上引入了-Si(OR)3功能团,通过溶胶-凝胶过程合成了PMMA/TiO2杂化聚合物材料.溶剂抽提结果表明有化学键存在的杂化材料体系中凝胶的含量很高.通过FTIR测试对材料结构进行了分析,由TGA、DSC测试分析了杂化材料体系中无机组份的含量对材料性能的影响. 相似文献