原位插层聚合法制备共聚酯/蒙脱土纳米复合材料

采用原位插层聚合法,制备了蒙脱土含量较高的共聚酯/蒙脱土纳米复合材料,意在做母料使用,含有该母料的聚合物复合材料的染色性能、吸湿浸润性能、抗静电性能及抗紫外性能等都有所改善。阐述了合适的共聚酯/蒙脱土纳米复合材料的制备工艺,讨论了制备过程中的影响因素,结果发现:在采用酯交换-缩聚反应釜进行原位插层聚合制备共聚酯/蒙脱土纳米复合材料的过程中,蒙脱土在缩聚釜中加入更符合生产实际;缩聚反应的实际过程证明了蒙脱土中含有的金属离子对缩聚反应有催化作用;另外,控制聚合的最终温度不超过278℃。最后,对共聚酯/蒙脱土纳米复合材料的结构进行了表征。     

铜离子-氧化锌/十六烷基铵基吡啶-蒙脱石吸附大肠杆菌的能力

以蒙脱石(montmorillonite,MMT)、铜离子(Cu2 )、氧化锌(ZnO)和十六烷基铵基吡啶(cetylpyridinium,CP)为主要原料,制备了MMT基系列细菌吸附剂Cu2 -ZnO/CP-MMT,Cu2 -ZnO/MMT,ZnO/MMT和MMT,并比较它们吸附大肠杆菌(Escherichia coli,E.coli)的能力.结果表明:上述材料与E.coli作用1.5 h后均可达到吸附平衡,吸附率大小顺序为Cu2 -ZnO/CP-MMT＞Cu2 -ZnO/MMT＞ZnO/MMT＞MMT.介质的pH值、离子强度和吸附温度对MMT基矿物材料吸附E.coli的能力有不同程度的影响.MMT基矿物材料吸附E.coli为吸热过程,在实验温度范围内自发进行.     

SBS/MMT共混物改性沥青性能的研究

利用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)与蒙脱土(MMT)制备了不同m(SBS):m(MMT)的共混物,探讨了共混物中m(SBS):m(MMT)对改性沥青物理机械性能、高温贮存稳定性、相形态及动态力学性能的影响。同时,对SBS/MMT用量和质量比相同的共混物改性沥青与直接改性沥青的性能作了对比分析。结果表明:利用SBS/MMT共混物对沥青进行改性在保持试样较好的低温性能的同时,能够明显提高沥青的高温贮存稳定性及高温动态力学性能,整体改性效果优于SBS/MMT直接改性沥青。     

蒙脱石预处理对制备柱撑蒙脱石的促进作用研究

在制备柱撑蒙脱石的过程中，首次提出了蒙脱石的预处理工艺，并以莱西钙基膨润土为原料，研究了预处理方法、预处理时间、料浆浓度、分散剂种类及用量对蒙脱石分散程度的影响，将钙基蒙脱石颗粒分散达到0.964 μm。经过预处理后，用钙基蒙脱石直接制备柱撑蒙脱石，并用SEM、XRD、DTA-TG和SRF等进行了表征。经300 ℃焙烧2 h后，其层间距为1.262 nm，热稳定性达588 ℃，此法省去了蒙脱石的钠化改性，简化了制备工艺。     

有机小分子季铵盐插层蒙脱石的制备综述

膨润土是一种很重要的非金属矿物,我国膨润土矿资源十分丰富,储量仅次于美国居世界第二位。本文介绍了有机膨润土的制备原理,制备工艺及制备过程中的关键因素。     

高吸水复合材料吸水速度的研究

本研究使用聚丙烯酰胺与蒙脱土复合而成的高吸水复合材料(简称SAPC)对其在各种情况下的吸水速度进行初步的探讨,测定了材料的吸水速度,讨论了水溶液中离子(盐)和醇浓度以及温度、时间等各种因素对SAPC吸水率的影响及影响吸水速度的原因。     

Strength properties of polyimideamide nanocomposite fibers in terms of their porous and supermolecular structure

The strength properties of fibers made from polyimideamide (PIA) nanocomposite were investigated and the effect of the presence of MMT in the fiber‐forming polymer on the porous structure and supermolecular structure of fibers was analyzed. It was found that lower strength properties (tenacity, elongation at break) of PIA nanocomposite fibers, as compared with those ones of fibers without montmorillonite (MMT), are connected with a lower deformability of the polymer during drawing stage and the collapse of MMT galleries, confirmed by WAXS investigations. This results in the formation of agglomerates that are weakly connected with the fiber‐forming polymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 339–344, 2007     

Dyeable polypropylene fibers via nanotechnology

Polypropylene (PP) nanocomposites with three different clay loadings were prepared by solution mixing technique. The solution‐mixed nanocomposites were extruded to fibers using a single screw extruder. The PP nanocomposite fibers obtained were uniformly dyed with three distinct disperse dyes at different levels of shade. The enhanced dyeability of PP nanocomposite fibers was characterized by spectrophotometric measurements. Satisfactory wash, light and crock fastness results were also achieved. Mechanical properties and degree of crystallinity of nanocomposite fibers with different clay loadings were also investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Morphological and Thermal Properties of ABS/Montmorillonite Nanocomposites Using ABS with Different AN Contents

Acrylonitrile‐butadiene‐styrene (ABS)/clay nanocomposites have been prepared using two types of ABS with different AN contents and a chemically modified clay, Cloisite 20A. The composites were prepared by melt mixing in a twin‐screw extruder. Their morphological properties were characterized by XRD and TEM. The thermal stability of the polymer nanocomposites was studied using TGA and flammability tests. The results were analyzed in terms of the effect of the clay content and the type of ABS used on the clay dispersion and the thermal stability of the nanocomposites. Experimental results confirmed that better dispersion and intercalation and/or exfoliation can be obtained when using an ABS with a higher AN content. The study using TGA and flammability tests showed that the nanodispersed layers of silicate enhanced the thermal stability of the ABS matrix, and that an ABS with higher AN content was more effective in providing fire retardancy. This suggests that when using higher AN contents, more polar groups are present within the polymer matrix, allowing a more homogeneous dispersion and intercalation of the chain polymers into the organomodified montmorillonite clay (MMT), and even some exfoliation of the nanoclay.

     

Bio‐Based Nanocomposites from Corn Oil and Functionalized Organoclay Prepared by Cationic Polymerization

A reactive organic montmorillonite clay (VMMT), modified with (4‐vinylbenzyl) triethylammonium cations, has been prepared and used as a nanofiller to reinforce a corn‐oil‐based polymer resin. The polymer resin was prepared by the cationic polymerization of conjugated corn oil, styrene and divinylbenzene, using boron trifluoride diethyl etherate modified with Norway fish oil as the initiator. The results indicate that the VMMT is intercalated in the corn‐oil‐based polymer resins. When compared with the pure polymers, these novel nanocomposites reinforced with 2 to 3 wt.‐% VMMT exhibit significant improvements in modulus, strength, strain and toughness. Furthermore, incorporating VMMT into the corn‐oil‐based polymer matrix also leads to improved thermal stability of the nanocomposites over the pure resins of up to 400 °C.