熔融插层法制备聚合物复合材料的研究进展

对近年来熔融插层法制备聚合物复合材料的研究进展进行了综述。从动力学、热力学方面对插层结果进行了分析，总结了影响插层效果的因索；并归纳出插层以后复合材料性质的改善，最后展望了熔融插层法制备聚合物／粘土纳米复合材料。     

SBS/粘土纳米复合材料的制备和性能研究

通过溶液插层法制备了苯乙烯—丁二烯—苯乙烯聚合物(SBS)／粘土纳米复合材料，并用X射线衍射透射电子显微镜分析其纳米分散结构及形态。研究结果表明：所得复合材料为插层型纳米复合材料；与SBS相比，SBS／粘土纳米复合材料断裂拉伸强度和300％定伸强度显著提高，储能模量明显提高。     

插层法制备聚合物/粘土纳米复合材料的原理

介绍了聚合物／粘土纳米复合材料的插层方法、制备原理和工艺过程,探讨了纳米复合材料微观结构的影响因素,概述了聚合物／粘土纳米复合材料的形成机理。     

纳米无机粒子补强天然橡胶的研究 (Ⅲ)纳米粘土/天然橡胶复合材料的研究

粘土是天然纳米片层材料,将改性后的纳米粘土采用插层法将聚合物基体或聚合物单体插入片层中,共聚共凝,制备的纳米粘土/聚合物复合材料表现出优异的综合性能,是近来研究的热点.本文综述了纳米粘土的改性以及插层法制备纳米粘土/天然橡胶复合材料的研究进展.     

橡胶／粘土插层纳米复合材料的研究进展

综述了橡胶／粘土插层纳米复合材料的制备方法及性能特征。重点介绍了溶液插层法、乳液插层法和熔体插层法及相关研究进展。评价了各种制备技术的优缺点,提出了橡胶／粘土插层纳米复合材料的发展趋势。     

熔融插层法制备聚合物/纳米蒙脱土的研究进展

简要介绍了熔融插层法制备聚合物／纳米蒙脱土复合材料的研究进展。结合热力学和动力学的分析，概括了熔融插层法一些理论上的研究进展。总结了目前关于熔融插层法制备聚合物／纳米蒙脱土复合材料及其表征的最新研究成果。     

天然橡胶／有机粘土纳米复合材料的制备与表征

自从丰田中心率先研究出了尼龙6／有机粘土纳米复合材料之后，聚合物／层状硅酸盐纳米复合材料引起了很多高分子科学家的关注。纳米复合材料就是一些无机填料以纳米级均匀分散在高聚物基体中形成的复合材料。粘土片层被聚合物插层或剥离可形成聚合物／粘土纳米复合材料。     

纳米复合材料插层技术的研究

在聚合物纳米复合材料中,聚合物／无机纳米复合材料占据主导地位。聚合物／无机纳米复合材料的制备方法主要有溶胶一凝胶(Sol-Gel)法、插层法、混合法。由于插层法方法简单,而且制备的聚合物纳米复合材料具有独特的性能,因此该方法在制备纳米复合材料时较为常用。     

聚丙烯/蒙脱土纳米复合材料的研究进展

对聚丙烯(PP)／蒙脱土(MMT)纳米复合材料的国内外研究进展进行综述,介绍了PP/MMT纳米复合材料的制备原理和制备方法。包括原位插层聚合法、聚合物溶液插层法、聚合物熔融插层法、溶胶一凝胶法,重点介绍了聚合物熔融插层法的研究进展。聚合物熔融插层法具有操作简单、无需处理过多溶剂的优点,避免了环境和能源问题,更易于工业化。最后对PP／MMT纳米复合材料的未来发展进行了展望。     

聚合物/粘土纳米复合材料的研究进展

综述了聚合物/粘土纳米复合材料的制备、表征和性能。粘土经相容剂修饰成为有机土,层间距增大,层间微环境由亲水变为亲油,从而利于聚合物的插层。聚合物插层导致粘土片层剥离并分散于聚合物基体中,得到的聚合物/粘土纳米复合材料的机械和物理性能比原来的聚合物材料有了显著的提高。     

聚丙烯/纳米黏土复合材料抗熔垂性能的研究

在双螺杆挤出机上制备了聚丙烯/纳米黏土复合材料;考察了其结构对其抗熔垂性能的影响。X射线衍射分析结果表明,实验得到了插层结构聚丙烯/纳米黏土复合材料,不同的聚丙烯基体和相容剂用量影响材料的插层结构。抗熔垂性能研究发现,不同的插层结构,抗熔垂性能不同。其中,黏土片层插层结构的层间距与材料抗熔垂性能存在一定关联,插层结构中黏土片层层间距过大或过小都不利于抗熔垂性能的改善,层间距为2.90-3.00 nm的插层结构的聚丙烯/纳米黏土复合材料具有较好的抗熔垂性能。     

The preparation of nano-clay/polypropylene composite materials with improved properties using supercritical carbon dioxide and a sequential mixing technique

A semi-continuous process using scCO₂ is reported for processing polymer–clay composites with high clay loading (i.e. 10 wt %) by reducing the collapse of the exfoliated clays. Two major modifications are involved in the new procedure: exfoliating the nano-clay directly into the hopper filed with pellets followed by processing the composite immediately and sequentially mixing the clay into the melt. This latter approach helped to minimize the clay collapse when processing the composites with high clay loadings. Transmission electron microscopy (TEM) and wide angle X-ray diffraction (WAXD) results are provided to investigate the effect of sequential mixing on reducing the clay collapse in the nanocomposite. Surface modified montmorillonite (MMT) nano-clay/polypropylene (PP) composite at 10 wt % nano-clay with improved clay dispersion was obtained with increased modulus and tensile strength of 63 % and 16%, respectively, compared to the pure PP matrix.     

纳米技术在聚合物改性方面的研究进展

综述了国内外纳米技术在聚合物改性方面的最新进展。无机纳米粒子改性聚合物的方法包括；直接生成法，原位生成法，插层复合法和反相微乳液法，其中直接生成法简单易行，但解决不了纳米粒子的团聚问题，其余方法则可使纳米粒子均匀分散在聚合物中形成纳米复合材料，无机纳米粒子改性后的聚合物既具有突出的力学性能，又有许多功能性，综合了无机，有机，纳米材料的优良性能，在许多领域有广阔的应用前景。     

超声波辅助插层-剥离法制备煤系高岭土微粉的研究

我国煤系高岭土储量丰富,为满足造纸、纺织等行业个性化的需求,通常要对其进行深加工。以山西朔州煤系高岭土为原料,分别在恒温磁力搅拌和超声波作用下探究了煤系高岭土/二甲基亚砜(DMSO)插层复合物制备的最佳条件,在插层复合物的基础上对煤系高岭土进行超声辅助剥离,制备得到高岭土微粉,并利用XRD、SEM、BET、TG-DSC等方法分析表征样品。正交实验结果表明在磁力搅拌条件下DMSO用量、插层时间以及插层温度均对插层率具有一定的影响,引入超声波有利于高岭土插层率的提升。插层复合物经超声辅助剥离后晶粒厚度明显减小,高岭土片层状结构大体上呈现碎片化,仅保留少部分大的片状结构,其边缘碎化,整体上也出现碎裂的趋势。剥离样品的比表面积和孔径均大幅度增加,为硬质高岭土的剥离和超微细粉体的制备提供了新的思路。     

Investigation of the effect of nano-clay type on the non-isothermal crystallization kinetics and morphology of poly(3(R)-hydroxybutyrate) PHB/clay nanocomposites

PHB is a thermoplastic biopolymer produced by fermentation of renewable resources. Secondary crystallization during storage leading to an increased degree of crystallinity is a principal reason of PHB brittleness. In addition, pure PHB has no residues of catalysts, meaning low nucleation density and slow crystallization rates, leading to the formation of large spherulites with cracks and brittleness. To overcome the brittleness of PHB, polymer composites based on PHB, plasticizers, and nano-clays A and B were prepared by solvent casting. The addition of plasticizer decreases T _g from 5 to ?13 °C in all composites. Furthermore, the addition of nano-clays acts as a nucleating agent to PHB. The effect of nano-clays A and B on spherulites morphology, thermal behavior, and crystal structure of PHB composites were tested by several techniques. Differential scanning calorimetry analysis shows that the addition of nano-clay A does not change the crystallization temperature and the crystallization half-time (t _1/2) of the PHB matrix but that nano-clay B accelerates the crystallization process. Thermogravimetric analysis revealed an increase in thermal stability of composites containing nano-clay B. Polarized optical microscopy showed that nano-clays serve as nucleating agents in PHB matrix. Therefore, the spherulites become smaller and the nuclei density increases at the selected crystallization temperature, compared to pure PHB.     

四溴双酚-A阻燃体系在HIPS／OMMT复合材料中的阻燃性研究

采用熔融插层法分别制备高抗冲苯乙烯／有机蒙脱土（HIPS／OMMT）复合材料和四溴双酚-A／三氧化二锑（TBBPA—Sb2O3）体系阻燃的HIPS／OMMT复合材料,透射电镜研究表明,有机蒙脱土均匀地分散于HIPS基体当中,形成了插层复合结构,锥形量热仪和氧指数仪研究表明：与纯的HIPS相比,HIPS／OMMT复合材料的阻燃性和抑烟性有所提高,但阻燃性的提高幅度较有限：与仅添加OMMT时的HIPS／OMMT复合材料相比,添加相同量OMMT时TBBPA—Sb2O3体系阻燃的HIPS／OMMT复合材料的热释放速率（HRR）和热释放速率峰值（PHRR）均有所降低,氧指数有所增加,且随TBBPA—Sb2O3阻燃剂添加量的增加阻燃性能的提高越明显,但TBBPA—Sb2O3的加入会导致聚合物燃烧过程生烟速率和生烟量的显著增加．因此此类阻燃剂的加入量不宜过高。     

Dispersion of nano-clay at higher levels into polypropylene with carbon dioxide in the presence of maleated polypropylene

The use of supercritical carbon dioxide (scCO₂) has proven to be beneficial for surface modified montmorillonite (MMT) nano-clay dispersion up to 6.6 wt% in a polypropylene (PP) matrix and lead to improved material mechanical properties in our earlier research. Our further modifications of the processing procedure including a sequential mixing technique successfully extended the technique to PP composites with as much as 10 wt% of clays and continuously increasing mechanical properties. In order to obtain additional enhancements of the composite properties at this clay level, polypropylene grafted with maleic anhydride (PP-g-MA) is included in this work. The results from the studies of the mechanical properties, rheological properties, and transmission electron microscopy (TEM) show that PP-g-MA is greatly beneficial in generating an exfoliated nano-clay morphology. Greater enhancements in the mechanical properties and nano-clay dispersion in the polymer matrix are observed when PP-g-MA is combined with the scCO₂ and sequential mixing techniques. The PP-g-MA based nano-clay composites have a high degree of exfoliated structure even with the addition of up to approximately 10 wt% nano-clay when using this technique, with mechanical properties such as yield strength and Young's modulus being increased by as much as 12 and 88%, respectively, relative to the polymer matrix. It is believed that the modulus reported here is the highest reported in the literature for conventional PP's.     

Development and evaluation of a biocide release system for prolonged antifungal activity in finishing materials

This paper focuses on the use of modified nano-clay particles as a controlled release system for biocides from building materials. Different (model) biocides were incorporated in a biocide/nano-clay composite and subsequently the release of the biocides was monitored under different environmental conditions. In addition, the biocide/clay material was formulated into a model finishing material (gypsum) to evaluate the antifungal activity. Intercalation of biocides in modified nano-clays was found to significantly prolong the release of the biocide and prevent premature leaching of the biocide from the building material. Release rate of the biocide could be tuned by selection of the type of modification used for the nano-clay platelets. Even after prolonged leaching up to 45 days in artificial rain tests, gypsum samples containing biocide/clay composites did not show any fungal growth, whereas gypsum samples containing pure biocide had lost their antifungal activity after exposure to artificial rain for 7 days or more, demonstrating the potential of this technology for practical applications. The presented approach is very versatile, and may be used for a large variety of biocides and is envisioned to be applicable to different construction and finishing materials, including waterborne paints. To optimize the performance in a specific application area, the leaching or release process of the nano-clays should be known in the different application materials, and consequently requires alternative testing methods, e.g. methods which characterize the fungal growth as a function of release in more detail. Although correlation with practice requires further investigation, the presented method gives a good first indication for prolonged protection of building materials.     

麦羟硅钠石/聚合物纳米复合材料研究进展

麦羟硅钠石（magadiite）是一种新型的层状纳米硅酸盐材料,由于其具有制备工艺简单、比表面积大、阳离子交换性能高、吸附性能强、层间膨胀性能好等优点,成为纳米材料提升聚合物性能最具有发展潜力的材料之一。本文主要综述了麦羟硅钠石/聚合物纳米复合材料的常用制备方法及其优缺点,包括聚合物插层法、单体原位插层聚合法、锚固插层聚合法。浅谈了国内外利用3种方法制备的基于聚苯乙烯、聚丙烯、环氧树脂、尼龙6、聚己内酯和聚甲基丙烯酸甲酯等多种聚合物的麦羟硅钠石/聚合物纳米复合材料,对在纳米复合材料结构中出现界面不相容、麦羟硅钠石分布不均匀的问题提出了解决方法,并阐述了麦羟硅钠石对纳米复合材料结构和性能的影响,最后展望了麦羟硅钠石/聚合物纳米复合材料的发展前景。     

高岭石有机插层复合材料的研究及应用现状

高岭石是一种层状硅酸盐矿物,有机物可进入其层间形成高岭石有机插层复合物。本文综述了高岭石有机插层复合物的发展及其制备,分析了高岭石插层复合物的插层反应特点和插层影响因素,并概述了该领域目前的研究重点和应用前景。