聚合物/蒙脱土纳米复合材料的研究进展

介绍了蒙脱土的结构特点，聚合物／蒙脱土复合材料的帛备方法和分类，讨论了各种聚合物／蒙脱土纳米复合材料的性能特点和应用。聚合物／层状硅酸盐蒙脱土纳米复合材料具有优异的性能，是目前材料学科研究的热点之一。     

聚合物/层状硅酸盐纳米复合材料的制备研究

本文以聚丙烯和有机蒙脱土为原料，采用插层复合法制备聚合物／层状硅酸盐纳米复合材料，用透射电镜对复合材料的结构进行表征，测定了复合材料的力学性能，结果表明，用马来酸酐化聚丙烯作界面相容剂，聚丙烯大分子链分子插层进入到有机改性蒙脱土的硅酸盐片层中间，并且聚丙烯／蒙脱土纳米复合材料的力学性能有一定的提高。     

HDPE／PC／相容剂／蒙脱土复合材料性能的研究

研究了HDPE／PC／增容剂／蒙脱土共混复合体系的力学性能和熔体的流变性能。结果表明，加入适量的增容剂和蒙脱土对HDPE／PC复合材料力学性能有一定的提高。在所研究的剪切应力、剪切速率、温度及组成范围内，该复合材料的lgη-lgγ曲线都偏离牛顿流体曲线，为非牛顿假塑性流体。经过有机化处理的蒙脱土复合材料体系比未经有机化处理的蒙脱土复合材料体系有更好的流动性和力学性能。     

PA6/蒙脱土熔融插层复合材料结构与性能分析

通过熔融共混法插层复合制备了聚酰胺(PN)6／蒙脱土纳米复合材料，测试了力学性能并对不同蒙脱土含量的PA 6／蒙脱土纳米复合材料进行了对比。实验表明，通过熔融插层可使PN 6基体插层于蒙脱土中，所得到的复合材料的性能较PN 6有很大提高。蒙脱土特殊的层状结构使得利用熔融共混在机械力的作用下插层到纳米级复合材料成为可能。     

尼龙/蒙脱土纳米复合材料研究进展

介绍了尼龙／蒙脱土纳米复合材料的制备方法，并对国内外关于尼龙／蒙脱土纳米复合材料热性能、力学性能、流变性能、结晶性能以及插层动力学研究进展进行了综述。结果认为，尼龙／蒙脱土纳米复合材料是一种新型的复合材料，蒙脱土的加入，改进了尼龙的力学性能，提高了复合材料的热变形温度。     

层状硅酸盐／橡胶纳米复合材料（一）：用熔融插层法提高层状硅酸盐／天然橡胶纳米复合材料的工艺和加工性能

天然橡胶纳米复合材料是通过天然橡胶与有机改性的硅酸盐熔融复合制备的。该研究亦对比使用了未有机化的原始层状硅酸盐和非层状硅酸盐（EIC）。所用的层状硅酸盐是钠皂土（BNT）；而所用的有机粘土则是以十八烷基铵类改性的蒙脱土（MMT-ODA）和以甲基牛脂基双（2-羟乙基）季铵类改性的蒙脱土（MMT-TMDA）。采用加有促进剂的硫黄硫化体系进行硫化。借助X-射线衍射和透射电子显微镜研究这些硅酸盐的分散。加入有机粘土的纳米复合材料显示出较快的硫化速度和提高了的物理机械性能。复合材料的物理机械性能提高度按如下顺序排列：MMT-ODA〉MMT-TMDA〉EIC〉BNT。这种性能的提高归因于有机硅酸盐的插层／剥离，而硅酸盐的插层／剥离行为又是因其层内间距较大所致。     

HDPE/PA6/OMMT复合材料的结构及性能研究

采用熔融插层法制备了HDPE／PA6／OMMT纳米复合材料,用XRD、TEM和SEM对复合材料进行了表征。测试表明,聚合物大分子链已经插层进入蒙脱土片层之间,形成了插层型纳米复合材料。当蒙脱土添加量为3phr时,蒙脱土以完全剥离的形态分散在分散相PA6中;当用量增加至7phr时,使得两相的结构发生了逆转,即多组分的HDPE成为分散相,而PA6成为连续相。当蒙脱土用量为3phr时复合材料表现出最佳的机械性能。     

蒙脱土改性纳米复合乳液的研究进展

纳米技术是一项前沿科学技术,目前,聚合物,蒙脱土纳米复合材料是重要的工程材料之一。由于蒙脱土具有层状硅酸盐的特殊结构,使得聚合物,蒙脱土纳米复合材料的各项性能均得到较大改善。介绍了蒙脱土的特性及其复合材料的结构,详细介绍了近年来国内外学者采用共混法和插层聚合法制备蒙脱土改性纳米复合乳液所做的研究工作。对蒙脱土改性不同乳液的应用研究现状进行了综述。指出了乳液法制备聚合物／蒙脱土纳米复合材料研究中存在的问题和应努力的方向。     

插层法制备聚合物/蒙脱土纳米复合材料的研究进展

对插层法制备聚合物／蒙脱土纳米复合材料的国内外研究现状作了简要的回顾，并对聚合物／蒙脱土纳米复合材料的力学性能、结晶性能、阻隔性能、热稳定性、各向异性及阻燃性能进行了综述。     

硅烷偶联剂对蒙脱土/NR纳米复合材料气体阻隔性能的影响

试验研究硅烷偶联剂对蒙脱土（MMT）／NR纳米复合材料性能的影响。结果表明，在MMT／NR复合材料中加入硅烷偶联剂，可提高复合材料的物理性能、耐热空气老化性能、气体阻隔性能和热稳定性。硅烷偶联剂KH-560的改性效果最好，其最佳用量为3份。     

Montmorillonite clay/poly(methyl methacrylate) hybrid resin and its barrier property to the plasticizer within poly(vinyl chloride) composite

A poly(methyl methacrylate) (PMMA)‐clay hybrid resin was prepared via bulk polymerization methyl methacrylate monomer in the presence of montmorillonite intercalated with an ammonium salt of dctadecylamine. The products were characterized by infrared spectroscopy, X‐ray diffraction, pyrolysis gas chromatography, and transmission electron microscopy. Results confirm that the resin is intercalated with PMMA molecules. The layer spacing of montmorillonite are enlarged, whereas the silicate layers are homogeneously dispersed individually. When the PMMA‐clay hybrid was blended with plasticized poly(vinyl chloride), the resulting composite exhibited excellent barrier property in preventing the plastizer's migration from the inner matrix to the surface of the product. This is presumably caused by barrier property of the silicate layers dispersed in the composite. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 425–430, 1999     

Overview of Various Sorts of Polymer Nanocomposite Reinforced with Layered Silicate

Polymer/layered silicate nanocomposites represent an important class of materials in which polymer is hardened by homogeneously dispersed inorganic particles. The most widely used nanoclay is bentonite which mainly consists of montmorillonite. Nanoclays are known to form composites with epoxy resin, polystyrene, poly(methyl metacraylate), polyvinyl chloride, and ternary blends. An outline of advancement in polymer-layered silicate nanocomposite is presented with different preparation methods such as in situ polymerization, solution-induced intercalation, and melt processing. The property enhancement comprises increased strength, decreased flammability, higher modulus, thermal stability, and barrier properties. Thermal, mechanical, and nonflammability property improvement has resulted in automotive and industrial applications.     

Structure and properties of nanocomposites based on poly(butylene succinate) and organically modified montmorillonite

Poly(butylene succinate) and organically modified montmorillonite nanocomposites with there different compositions were prepared via melt blending in a twin‐screw extruder. The structure of the nanocomposites was studied with X‐ray diffraction and transmission electron microscopy, which revealed the formation of intercalated nanocomposites, regardless of the silicate loading. Dynamic mechanical analysis revealed a substantial increase in the storage modulus of the nanocomposites over the entire temperature range investigated. The tensile property measurements showed a relative increase in the stiffness with a simultaneous decrease in the yield strength in comparison with that of neat poly(butylene succinate). The oxygen gas barrier property of neat poly(butylene succinate) improved after nanocomposite preparation with organically modified montmorillonite. The effect of the layered‐silicate loading on the melt‐state linear viscoelastic behavior of the intercalated nanocomposites was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 777–785, 2006     

Technological and processing properties of natural rubber layered silicate‐nanocomposites by melt intercalation process

Natural rubber nanocomposites were produced by melt‐mixing of natural rubber with organically modified silicates. For comparison, a pristine‐layered silicate and a nonlayered version [English Indian clay (EIC)] were also included in the study. The layered silicate used was sodium bentonite (BNT) and organoclays used were octadecylamine‐ modified montmorillonite (MMT‐ODA) and methyltallow bis‐2‐hydroxyethyl ammonium‐modified montmorillonite (MMT‐ TMDA). Accelerated sulfur system was used for the vulcanization of the nanocomposites. The dispersion of these silicates was studied by X‐ray diffraction and transmission electron microscopy. The organoclay‐incorporated composites exhibited faster curing and improved mechanical properties. The improvement in the mechanical properties of the composites followed the order MMT‐ODA > MMT‐TMDA > EIC > BNT. The property improvement was attributed to the intercalation/exfoliation of the organically modified silicates because of their high initial interlayer distance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2537–2543, 2006     

废旧PE-HD/OMMT纳米复合材料热氧老化性能和燃烧性能研究

以废旧高密度聚乙烯（PE-HD）和蒙脱土（MMT）为原料,采用熔融插层法制备纳米复合材料,考查制备工艺对该材料热氧老化性能和燃烧性能的影响。结果表明,PE-HD复合MMT或有机蒙脱土（OMMT）后,抗热氧老化性能显著降低,阻燃性能增强;十六烷基三甲基溴化铵（CTAB）、OMMT、马来酸酐（MAH）和过氧化二异丙苯（DCP）加入量分别增加时,PE-HD/OMMT纳米复合材料的抗热氧老化性能无显著变化,阻燃性能呈现先增强后降低或稳定的趋势;当CTAB加入量为1 %、OMMT加入量为3 %、MAH和DCP加入量为1.5 %时,PE-HD/OMMT纳米复合材料的极限氧指数达到19.4 %,阻燃性能最好。     

阻隔性聚合物/蒙脱土纳米复合材料的开发

介绍了聚合物／蒙脱土纳米复合材料的制备方法和主要特性，重点综述了阻隔性聚合物／蒙脱土纳米复合材料的开发进展，包括聚酰胺(PA)／蒙脱土纳米复合材料、聚对苯二甲酸乙二醇酯(PET)／蒙脱土纳米复合材料、聚苯乙烯(PS)／蒙脱土纳米复合材料、超高相对分子质量聚乙烯(UHMWPE)／蒙脱土纳米复合材料。     

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.     

Preparation and properties of layered silicate/polyimide hybrid films

Layered silicate/polyimide (PI) hybrid films were prepared from 4,4′‐oxydianiline, 3,3′,4,4′‐oxydiphthalic anhydride, and chemically modified montmorillonite via an in situ intercalation polymerization pathway. The X‐ray diffraction and transmission electron microscopy results indicated that the silicates were homogeneously dispersed as exfoliated layers in the PI hybrid film with 2% silicate. The mechanical properties and thermal stabilities of the PI hybrid films changed with the content of the layered silicates. The coefficient of thermal expansion and water uptake of the PI hybrid films decreased with increasing silicate contents because of the barrier effect of platelike silicate layers, which prevented the diffusion and penetration of water. The dielectric strength and electrical aging performance of the PI hybrid films could also be improved as the silicate layer highly dispersed in the films. For the hybrid PI film with 5% layered silicate, the time to failure during electrical aging exceeded 280 h, which was 2.5 times as long as that of pure PI film. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1176–1183, 2005     

聚合物/层状纳米填料阻隔复合薄膜研究进展

综述了层状纳米复合材料的制备方法,以蒙脱土(MMT)、层状双氢氧化物(LDHs)和石墨烯(GNSs)为典型例子,系统阐述了层状纳米填料改善聚合物薄膜阻透性能的机理,最后讨论了高阻透、多功能化的纳米复合薄膜在制备及应用中所面临的挑战。     

Effect of non-ionic surfactants on the exfoliation and properties of polyethylene-layered silicate nanocomposites

Nanocomposites of high-density-polyethylene (HDPE) and organically (dimethyldioctadecylammonium) modified montmorillonite (OM) were prepared and the effect of non-ionic surfactants on the OM exfoliation and composite properties (tensile+gas-permeation) was studied. Amphiphilic block and random copolymers of different chemical structures were used as dispersing agents. The presence of copolymers in the composites led to polymer intercalation that increased the d-spacing and facilitated the exfoliation. Consequently, the permeability coefficient (oxygen) of the nanocomposites was decreased and their stiffness increased. End-functionalized oligomers proved to be more efficient in dispersing the OM than copolymers in which the polar units are randomly distributed along the polymer chain. Poly(ethylene-co-vinyl alcohol) increased the d-spacing but did not improve the properties of the composite probably due to ‘bridging’ the silicate layers, which hindered the exfoliation. The OM exfoliation could be enhanced to such an extent that an inclusions' average aspect ratio of 150 was estimated from the oxygen-permeation measurements. With increasing exfoliation, the stiffness, strength and gas-barrier properties of the composites improved significantly. The oxygen permeability of the HDPE nanocomposites was cut to less than half, thus offering a strong barrier to oxygen and humidity useful for food and drug packaging.