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聚合物/层状硅酸盐(PLS)纳米复合材料是近十多年迅速发展起来的新交叉科学。由于聚合物纳米复合材料具有常规聚合物复合材料所没有的结构、形态以及较常规聚合物复合材料更优异的物理力学性能、耐热性和气体液体阻隔性能等,因而显示出重要的科学意义和应用前景。综述了聚合物/层状硅酸盐纳米复合材料的制备、结构、性能和应用情况,最后展望了其应用前景。 相似文献
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聚合物/层状硅酸盐纳米复合材料制备原理 总被引:19,自引:1,他引:18
围绕着分散相尺寸和两相界面粘接这两个关键问题,简单回顾了复合材料从熔融共混,聚合复合到纳米复合的发展历程。通过对具有重要理论意义和应用价值的聚合物/层状硅酸盐(PLS)纳米复合材料制备过程热力学驱动力的考察以及制备原理的分析,我们首次从理想状态下推导出了能在一定范围内预测聚合物相对分子质量与层状硅酸盐含量,层状硅酸盐片层间距与层状硅酸盐含量以及层状硅酸盐片层间距与聚合物相对分子质量关系的理论公式,并用文献中的实验数据进行了验证。结果表明这些理论关系与文献中的实验数据精确吻合。 相似文献
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聚合物/层状硅酸盐纳米复合材料 总被引:1,自引:0,他引:1
目前,聚合物/层状硅酸盐纳米复合材料是重要的工程材料之一。由于层状硅酸盐的特殊结构,聚合物层状硅酸盐纳米复合材料的各项性能得到较大改善。聚合物/层状硅酸盐纳米材料的制备、表征、结构与性能的研究取得了重要进展。本文简要概述了聚合物/层状硅酸盐的结构及其有机改性机理,研究表明,插层剂和离子交换容量是插层的重要因素。最后,讨论了聚合物/层状硅酸盐纳米复合材料的制备方法和性能。 相似文献
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聚合物—层状硅酸盐纳米复合材料制备及应用 总被引:49,自引:0,他引:49
聚合物-层状硅酸盐(PLS)纳米复合材料因其优异的性能是目前材料科学研究的热点,简要回顾PLS纳米复合材料研究发展的概况,概述PLS纳米复合材料的特点,种类,微观结构与物理力学性能,着重介绍PLS纳米复合材料的各种制备方法和原理,并从热力学角度对插层复合过程进行了分析,讨论了层状硅酸盐的表面修饰,提出了插层剂的选择原则,展望了PLS纳米复合材料的应用前景。 相似文献
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简述聚烯烃/层状硅酸盐纳米复合材料的结构、表征及优点,并对采用熔融插层法制备的此种复合材料的力学性能、结晶性能及相关工艺、表征方法、分散机理等进行较为详细的综述。 相似文献
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层状硅酸盐 /聚合物纳米复合材料的研究现状与前景 总被引:13,自引:0,他引:13
基于1996年以后的40余篇文献和作者的研究成果,综述了层状硅酸盐/聚合物纳米复合材料在制备技术、新品种、新性能、相关理论及应用等方面的最新研究进展,并总结出了以下观点:(1)粘土的有机化是制备纳米复合材料的第一关键要素,单体、预聚体、聚合物熔体与有机土的相容性是制备纳米复合材料的必要条件,外界剪切力可提供帮助;(2)剥离型结构最能体现层状硅酸盐/聚合物纳米复合材料的性能优势,是层状硅酸盐/聚合物纳米复合材料的制备方向;(3)聚合物熔体插层法为简单,是重要的发展方向,要形成剥离型结构,需要同时考虑热力学和动力学因素,基体或相容剂与层间环境的相容性要适中;(4)聚合物乳液共混共凝法有利于传统的制备方法,适合于具有乳液形成的聚合物;(5)在聚合物中原位生成硅酸盐片层的方法具有新意;(6)层状硅酸盐/聚合物纳米复合材料的主要特点是高刚性、高强度、高耐热性、高阻隔性、较好的阻燃性、质轻,目前,该的制备研究正向所有的聚合物品种扩展。汽车部件、包装材料将是层状硅酸盐/聚合物纳米复合材料先应用的两大领域;(7)层状硅酸盐/聚合物纳米复合材料的理论研究进展延慢。界面区状态以及结构-性能间的关系是理论研究的两个主题。 相似文献
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呈层状构造的硅酸盐,利用在其层间具有插入多种单体或聚合物的能力,可能开发新的聚合物/硅酸盐层状纳米复合材料,并且,由于细微调整硅酸盐的表面特性,在几种聚合物基体中,使硅酸盐纳米级分散成功了。所得的聚合物/硅酸盐(PLS)层状纳米复合与同一硅酸盐体积比率比较时,与填充一般玻璃或无机矿物的聚合物相比有显著优异的性能。 相似文献
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Model reactions were carried out with components frequently used for the preparation of intercalated or exfoliated polypropylene (PP) nanocomposites. The results prove that maleinated polypropylene (MAPP) can react chemically with the surfactant applied for the organophilization of the filler, if this latter contains active hydrogen groups. The reaction of hexadecylamine (HDA) and MAPP was detected by MALDI-TOF spectroscopy, DSC measurements and FTIR spectroscopy. Anhydride groups are consumed and mainly amide groups form in the reaction. The formation of cyclic imides could not be proved by the techniques used. MAPP reacts also with the surfactant adsorbed on the surface of the silicate in ionic form. On the other hand, N-cetylpyridinium chloride (CPCl) not containing active hydrogen atoms does not react with maleinated PP. Intercalated or exfoliated composites could be prepared from the silicate organophilized with HDA, while microcomposites formed from the filler treated with CPCl. Chemical reactions remove the surfactant from the surface of MMT and hydrogenated silicate sites are left behind. The high energy surface interacts either with the anhydride or the amide groups by dipole-dipole interactions. Even the unmodified polypropylene chains may be attached much stronger to the surface by London dispersion forces than to the silicate covered with aliphatic chains. Although the effect of competitive adsorption (MAPP, HDA) and mutual solubility of the components (PP, MAPP, surfactant, reaction products) cannot be neglected, chemical reactions play a crucial role in structure formation in PP nanocomposites containing a functionalized polymer. Direct interaction of the silicate surface and the functionalized polymer as well as the formation of hydrogen bridges seem to play a lesser role, but the relative influence of processes may change with the type of surfactant, functionalized polymer, surface coverage and processing conditions. 相似文献
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The role of organically modified layered silicate as a compatibilizer for immiscible polystyrene (PS) with polypropylene (PP) or polypropylene grafted with maleic anhydride (PP-g-MA) blends was investigated. Scanning electron micrographs (SEM) revealed efficient mixing of the polymers in the presence of organically modified layered silicate. X-ray diffraction (XRD) patterns and transmission electron microscopic (TEM) observations showed that silicate layers were either intercalated or exfoliated, depending on their interactions with the polymer pair, and were located at the interface between the two polymers. The compatibilizing action of the organically modified layered silicate resulted in a decrease in interfacial tension and particle size and in a remarkable increase in mechanical properties of the modified immiscible blends. 相似文献
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The glass transitions of acrylonitrile-butadiene rubber (NBR)/organoclay nanocomposites with various silicate contents were investigated using positron annihilation lifetime spectroscopy (PALS). The nanocomposites were prepared through melt intercalation of NBR with various concentrations of organoclay (OC30B) modified with the organic modifier, methyl tallow bis(2-hydroxyethyl) quaternary ammonium (MT2EtOH), i.e., Cloisite® 30B. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) measurements of the NBR/OC30B nanocomposites showed that the NBR chains were intercalated between the silicate layers, thereby increasing the gallery heights of the organosilicates. The glass transition temperature of NBR was determined using differential scanning calorimetry (DSC). However, it seemed to be very difficult to clearly resolve the very small differences in Tgs caused from various loading of nanosized silicate in NBR/OC30B nanocomposites. Hence, we performed positron annihilation lifetime spectroscopy (PALS) on NBR/OC30B nanocomposites containing various amounts of OC30B (1-10 wt%). Significant changes in the temperature dependencies of free volume parameters (i.e., lifetimes and intensities) were observed at the transition temperature, Tg,PALS, and the Tg,PALS values were found to increase with increasing organoclay content in the samples. These observations are consistent with PALS having a higher sensitivity in the detection of very small changes in free volume properties. The present findings thus highlight the usefulness of PALS for studying phase transition phenomena in polymeric materials with nanoscale structural variations. 相似文献
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可生物降解聚合物中的层状硅酸盐纳米复合材料,可极大提高其力学性能,但同时会影响到材料的降解速率。研究纳米填料对可生物降解聚合物降解速率的影响及降解机理的变化,可拓宽其应用领域。综述聚乳酸(PLA)、淀粉、聚己内酯(PCL)、纤维素、聚羟基烷脂肪酸酯(PHA)、聚琥珀酸丁二醇酯(PBS)等可生物降解聚合物基层状硅酸盐纳米复合材料制备及降解性能研究现状及进展。 相似文献
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聚硅酸硫酸铝的生产技术与研究进展 总被引:1,自引:0,他引:1
聚硅酸硫酸铝是一种高效的复合型絮凝剂,具有广阔的应用前景。概述总结了聚硅酸硫酸铝的结构研究进展以及国内外的生产技术,并根据作者的实际研究经验对保证产品稳定性的关键技术进行了简要的评述,认为产品稳定性及混凝效果是影响其工业化的一个重要因素,如何提高产品稳定性是今后研究的一个重要方向。 相似文献