层状硅酸盐黏土/硅橡胶纳米复合材料的研究进展

层状硅酸盐黏土因其独特的纳米层状结构在改性硅橡胶高分子材料性能上具有明显的理论优势,其资源丰富、成本低和绿色无污染等特点在实际应用中受到广泛关注。本文综述了近年来层状硅酸盐黏土包括2∶1型结构如蒙脱石、凹凸棒石和1∶1型结构如高岭石、埃洛石等在改性硅橡胶高分子材料机理和性能方面的国内外最新研究进展,指出目前研究的重点主要集中在硅橡胶性能提高方面,如何使层状硅酸盐黏土粒子在硅橡胶基体中达到最佳纳米分散状态,从而获得性能优异的纳米复合材料是研究的难点。同时,展望了层状硅酸盐黏土/硅橡胶纳米复合材料的发展前景,旨在为层状硅酸盐黏土改性和高性能硅橡胶纳米复合材料的研究提供借鉴。     

生物降解高分子/层状硅酸盐复合材料研究进展

生物降解高分子作为环境友好型材料受到人们的关注,近年来国内外对它开展了广泛的研究,但其在实际应用中存在一定的局限性.采用层状硅酸盐制备生物降解高分子复合材料可有效提高和改善生物降解高分子的性能,扩大其应用范围.生物降解高分子/层状硅酸盐复合材料是一种新兴的先进材料,系统地综述了国内外有关生物降解高分子/层状硅酸盐复合材料的研究现状及发展趋势.     

生物可降解聚乳酸/层状硅酸盐纳米复合材料的研究进展

生物可降解聚乳酸是一种具有广泛应用前景的环境友好型的生物高分子材料,但是其力学性能、热稳定性能不稳定.利用层状硅酸盐的特殊结构,以各种有机改性的层状硅酸盐为添加物,通过原位插层聚合、溶液插层、熔融插层和剥离.吸附等方法制备生物可降解聚乳酸/层状硅酸盐纳米复合材料,其力学性能、热稳定性、生物降解性等均有显著提高,其展现出极其广阔的应用前景.本文概述了近年来生物可降解聚乳酸/层状硅酸盐纳米复合材料的制备、结构、性能和应用等方面的研究进展,并且对各种制备方法进行了分析比较.     

聚合物/层状硅酸盐纳米复合材料的研究现状

介绍了层状硅酸盐粘土的结构与性质,归纳总结了聚合物/层状硅酸盐纳米复合材料的制备方法以及目前国内外的研究进展,并对纳米复合材料的制备过程进行了热力学及动力学分析.     

层状硅酸盐纳米复合材料的阻燃研究及现状分析

聚合物/层状硅酸盐(PLS)纳米复合材料是国内外阻燃材料领域中近年来研究的热点。它满足了新型阻燃材料发展的要求,在提高阻燃性能的同时能够很少降低或者不降低材料原有的其他性能,有时甚至可以提高部分聚合物基体的机械性能、气体阻隔性能、环保性能等。本文综述了聚合物/层状硅酸盐纳米复合材料的研究近况;简要介绍了该纳米复合材料的特点及阻燃性能的测试;讨论了其燃烧性能和阻燃机理;重点研究了以聚酰胺(PA)等聚合物为基质、以层状硅酸盐为无机阻燃添加剂的纳米复合材料的阻燃性能。通过与常规阻燃剂进行比较,发现聚合物/层状硅酸盐纳米复合材料在阻燃性能、机械性能、加工性能和环保等方面均优于常规阻燃剂;最后本文还指出了该材料在阻燃研究中目前尚存在的问题,并对其开发应用前景进行了展望。     

聚合物-层状硅酸盐纳米复合材料应用研究进展

笔者论述了聚合物-层状硅酸盐插层纳米复合材料的结构和特点，综述了聚合物-层状硅酸盐纳米复合材料的应用研究进展，评述了聚合物-层状硅酸盐纳米复合材料的制备方法和表征手段，展望了这种纳米复合材料的发展方向。     

可降解热塑性淀粉/层状硅酸盐纳米复合材料的研究进展

热塑性淀粉/层状硅酸盐纳米复合材料具有常规热塑性淀粉材料所没有的结构、形态以及较常规热塑性淀粉材料具有更优异的机械性能、耐热性能和气体、液体阻隔性能等而显示出重要的科学意义和应用前景.本文综述了目前国内外热塑性淀粉/层状硅酸盐纳米复合材料的发展现状,并对其应用前景进行了展望.     

聚丙烯/层状硅酸盐纳米复合材料研究进展

介绍了近年来国内外聚丙烯/层状硅酸盐纳米复合材料研究进展,分析了目前存在的问题和今后研究的方向,并简述了纳米聚丙烯的应用前景。     

聚乳酸/层状硅酸盐纳米复合材料研究进展

介绍了聚乳酸/层状硅酸盐纳米复合材料研究进展,阐述了其制备方法如原位聚合插层法、溶液插层法、熔融插层法等,详述了聚乳酸添加纳米层状硅酸盐后结构与性能的变化,包括复合材料的微观结构、结晶性能、热性能、力学性能、流变性能、加工性能、阻隔性能、阻燃性能的变化。研究表明,采用不同的制备方法如原位聚合插层法、溶液插层法、熔融插层法等能制得插层型、剥离型以及插层与剥离混合型聚乳酸/层状硅酸盐纳米复合材料;添加纳米层状硅酸盐后,得到的聚乳酸/层状硅酸盐纳米复合材料结晶速率提高,结晶度增加,说明层状硅酸盐起到了成核剂的作用;热稳定性、拉伸模量和冲击强度、阻透性能和阻燃性能都有不同程度提高;流变性能也得到改善。     

聚氨酯／层状硅酸盐纳米复合材料的研究进展

综述了近年来国内外纳米层状硅酸盐改性聚氨酯的最新研究进展状况。介绍了层状硅酸盐的结构、聚氨酯／层状硅酸盐纳米复合材料的类型及其微观结构,并对聚氨酯／层状硅酸盐纳米复合材料的制备方法及其在弹性体、涂料、泡沫方面的应用进行了阐述,展望了未来发展趋势。     

聚合物/层状硅酸盐纳米复合材料

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。     

Polymer layered silicate nanocomposites

Polymers filled with low amounts of layered silicate dispersed at nanoscale level are most promising materials characterized by a combination of chemical, physical and mechanical properties that cannot be obtained with macro‐ or microscopic dispersions of inorganic fillers. Polymer layered silicate nanocomposites can be obtained by insertion of polymer molecules in the galleries between the layers of phyllosilicate. Here, hydrated alkaline or alkaline earth metal cations are hosted which neutralize the negative charge resulting from isomorphous substitutions of Mg or Al cations within the silicate. Insertion of polymer molecules to prepare “intercalation hybrids” can be carried out by replacing the water hydration molecules in the galleries by polymers containing polar functional groups, using the so called ion‐dipole method. A more general technique involves compatibilization of the silicate by intercalation of an organic molecule, typically an organic alkylammonium salt, that replaces the cations in the interlayer galleries to form an organically modified layered silicate (OLS). The aliphatic chain of the OLS favors the intercalation of any type of polymer. Intercalated or delaminated polymer‐silicate hybrids are obtained depending on whether the stack organization of the silicate layers is preserved or is lost, with single sheets being distributed in the polymer matrix. The methods currently used for preparing polymer layered silicate (PLS) nanocomposites are: in situ polymerization, from polymer solution, or from polymer melt. Although PLS nanocomposites have been known for a long time, it is the possibility of preparing them by melt intercalation of OLS in processing that is boosting the present interest in these materials and their properties. So far PLS nanocomposites have been characterized by X‐ray diffractometry, transmission electron microscopy, differential scanning calorimetry, and NMR. Published results on PLS nanocomposites are reviewed concerning their characterization and properties with particular reference to fire retardant behavior.     

嵌入法制备聚合物/层状硅酸盐纳米复合材料的研究进展

本文介绍和对比了嵌入法制备聚合物／层状硅酸盐纳米复合材料的三种类型,与溶液嵌入法（包括单体嵌入聚合法和聚合物溶液嵌入法）相比,熔融嵌入法具有更广泛的适用性。并从热力学和动力学角度出发,分析了影响嵌入过程的各种因素。     

聚合物/层状硅酸盐纳米复合材料的研究进展 --层状硅酸盐粘土的有机改性

综述了近年来国内外聚合物/层状硅酸盐纳米复合材料领域中层状硅酸盐有机改性的最新研究进展情况.主要对有机改性剂的结构、作用机理、改性后有机粘土的特性,及其在聚合物基纳米复合材料中的应用进行了详细的阐述.在此基础上,提出了一条新的研究思路.     

聚合物／层状硅酸盐纳米复合材料制备原理

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。     

Poly(ethylene 2,6-naphthalate)/layered silicate nanocomposites: fabrication, crystallization behavior and properties

In this study, poly(ethylene 2,6-naphthalate) (PEN)/layered silicate nanocomposites (PLSNs) were successfully prepared by the intercalation of PEN polymer into organically-modified layered montmorillonite through the melt blending process. Both X-ray diffraction data and transmission electron microscopy images of PEN/layered silicate nanocomposites indicate most of the swellable silicate layers were exfoliated and randomly dispersed into the PEN matrix. Mechanical and barrier properties of the fabricated nanocomposites performed by dynamic mechanical analysis and permeability analysis show significant improvements in the storage modulus and water permeability when compared to neat PEN. Differential scanning calorimeter (DSC) was used to investigate the isothermal crystallization behavior and melting behavior of PLSNs. DSC isothermal results revealed that the crystal growth process of PEN and PLSNs are a three-dimensional spherulitic growth. The activation energy of PEN increases with increasing content of layered silicates. The result indicates that the addition of layered silicate into PEN reduces the transportation ability of polymer chains during crystallization processes.     

Nanocomposites: a new class of flame retardants for polymers

Nanocomposites are a new class of polymer systems. Modified layered silicates as fillers are dispersed at a nanometre-level within a polymer matrix and new extraordinary properties are observed. Through nanocomposite formation the thermal stability and flame retardancy of polymers are also improved. The flame retardancy of layered silicate nanocomposites is based on char formation and its structure. Dr. Günter Beyer of Kabelwerk Eupen AG in Belgium reviews the current state of development of nanocomposites as a new class of flame retardants for polymers.     

Synthesis and properties of poly(methyl methacrylate)/montmorillonite (PMMA/MMT) nanocomposites

PMMA/MMT nanocomposites were successfully synthesized via in situ intercalative polymerization, and characterized by means of wide‐angle X‐ray diffractometry, transmission electron microscopy, thermal gravimetric analysis, dynamic mechanical analysis and Fourier‐transform infrared analysis. The nanocomposites possess partially exfoliated and partially intercalated structure, in which the silicate layers are exfoliated into nanometre secondary particles with thickness of less than 20 nm and uniformly dispersed in the polymer matrix. In comparison with pure PMMA, the thermal stability, glass transition temperature, and mechanical properties of the polymer are notably improved by the presence of the nanometric silicate layers. It was found that part of the PMMA chains in the nanocomposites are well immobilized inside and/or onto the layered silicates and, therefore, the unique properties of the nanocomposites result from the strong interactions between the nanometric silicate layers and the polymer chains. Copyright © 2003 Society of Chemical Industry     

Fabrication and characterization of biodegradable poly(lactic acid)/layered silicate nanocomposites

In this study biocompatible/biodegradable poly(lactic acid) (PLA)/layered silicate nanocomposites (PLSNs) were successfully prepared by the intercalation of PLA polymer into organically modified layered silicate through the solution mixing process. Both X‐ray diffraction data and transmission electron microscopy images of PLSNs indicate most of the swellable silicate layers were disorderedly intercalated into the PLA matrix. Mechanical properties of the 0.1 wt% silicate‐containing fabricated nanocomposites performed by dynamic mechanical analysis have significant improvements in the storage modulus when compared to that of neat PLA matrix. Adding more layered silicates into PLA matrix induced a decrease in the mechanical properties of PLSNs, probably due to the presence of a large dimension of porosity in the fabricated nanocomposites. POLYM. ENG. SCI., 45:1615–1621, 2005. © 2005 Society of Plastics Engineers