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To better understand the effect of rectorite and carbon black (CB) on the aging performance of styrene-butadiene rubber (SBR), SBR/CB, SBR/CB/rectorite and SBR/rectorite nanocomposites with the same total filler loading were prepared. The microstructure of the three SBR nanocomposites was characterized by XRD, TEM and SEM. After thermal aging, oxygen-containing molecules were found to be formed in the SBR nanocomposites, as verified by FTIR analysis. The SBR/rectorite nanocomposite showed the highest aging coefficient and the lowest change rate of tensile strength and stress at 100% strain among the three SBR nanocomposites, indicating that the introduction of nano-dispersed rectorite layers can enhance the thermal aging resistance of the nanocomposites. For the SBR/CB/rectorite nanocomposite, the addition of CB helped to improve the interfacial compatibility between the filler and matrix, resulting in the best crack resistance as the aged SBR/CB/rectorite nanocomposite always demonstrated the least cracks on the surface during either stretching or bending experiments. 相似文献
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Natural rubber (NR)/rectorite nanocomposite was prepared by co-coagulating NR latex and rectorite aqueous suspension. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) were employed to characterize the microstructure of the nanocomposite. The results showed that the nanocomposite exhibited a higher glass transition temperature, lower tan δ peak value and slightly broader glass transition region compared with pure NR. The gas barrier properties of the NR/rectorite nanocomposites were remarkably improved by the introduction of nanoscale rectorite because of the increased tortuosity of the diffusive path for a penetrant molecule. The nanocomposites have a unique stress-strain behavior due to the reinforcement and the hindrance of rectorite layers to the tensile crystallization of NR. 相似文献
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聚丙烯/累托石纳米复合材料的非等温结晶动力学研究 总被引:2,自引:0,他引:2
在双螺杆挤出机上熔融共混制备了聚丙烯 (PP) 有机累托石 (OREC)纳米复合材料 ,采用广角X 射线衍射 (WAXD)定性地分析了PP OREC纳米复合材料及纯PP的结晶形态 ,由半峰宽定性地判断了对应晶面法向的晶粒的大小 .结果表明有机累托石没有改变聚丙烯的结晶晶型 (纳米复合材料主要还是α晶型 ) ,但是细化了晶粒的尺寸 .采用差示扫描量热法 (DSC)定量地研究了复合材料的非等温熔融结晶动力学 ,对所得数据分别用Jeziorny法的Mo法进行了处理 ,表明非等温结晶动力学参数Zc 及Avrami指数n随冷却速率的增加而增加 ,复合材料的Avrami指数n大于纯PP的n ;对相同配比的纳米复合材料 ,随着结晶度的增加 ,单位结晶时间里达到一定结晶度所需要的降温速率F(T)增大 ,对同一个设定的结晶度 ,纳米复合材料的F(T)比纯PP的小 ,说明需要的降温速率减小 .所有这些均说明有机累托石可作为聚丙烯的结晶成核剂 . 相似文献
4.
Teng Bao Jie Jin Mekdimu Mezemir Damtie Ke Wu Zhi Ming Yu Lie Wang Jun Chen Yong Zhang Ray L. Frost 《Journal of Saudi Chemical Society》2019,23(7):864-878
A zero-valent iron/rectorite nanocomposite (NZVI/rectorite) was developed as a heterogeneous H2O2 catalyst for P-chlorophenol degradation. The physicochemical properties of NZVI/rectorite were characterized by various techniques including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive spectrometry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis. Results showed that NZVI sphere nanoparticles were successfully loaded on the rectorite surface with less aggregation and good dispersion. Moreover, compared with acid-leached rectorite (30.91 m2/g), the NZVI/rectorite appeared to have larger surface area (50.75 m2/g). In addition, the effects of pH, reaction time, initial P-chlorophenol concentration, catalyst amount, and H2O2 dosage on the P-chlorophenol degradation were systematically investigated. Results showed that NZVI/rectorite presents better properties for the degradation and mineralization of P-chlorophenol compared with pristine NZVI due to the large surface area, low aggregation, and good dispersion of the former. The degradation mechanisms of P-chlorophenol by NZVI/rectorite were adsorption and reduction coupled with a Fenton-like reaction. Four successive runs of the stability and regeneration study also showed that the NZVI/rectorite were unchanged even after 100% of P-chlorophenol degradation ratio. This study has extended the application of NZVI/rectorite as environment function material for the removal of P-chlorophenol from the environment. 相似文献
5.
累托石粘土/热塑性聚氨酯弹性体纳米复合材料的研究 总被引:15,自引:0,他引:15
采用十二烷基季铵盐合成了一种有机累托石 (ORECA) ,并分别采用不同填充量 2 ,5 ,8份的累托石(REC)及ORECA 与热塑性聚氨酯弹性体 (TPUR)通过熔融共混制备出了粘土 /热塑性聚氨酯弹性体纳米复合材料 ;以红外光谱 (FTIR)、广角X 射线衍射分析 (XRD)、扫描电镜 (SEM)及Molau实验方法研究了REC及ORECA 在TPUR中的分散性 ,研究了复合材料的力学性能 .结果表明 ,ORECA 在质量分数小于 5份时可以和聚氨酯弹性体达到纳米复合 ,复合材料的拉伸强度提高 4 2 % ;撕裂强度在所加份数范围内呈现递增趋势 ,8份时撕裂强度提高 4 9% . 相似文献
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层状硅酸盐累托石/环氧树脂纳米复合材料的结构和性能研究 总被引:1,自引:0,他引:1
用有机改性的层状累托石与环氧树脂复合制备出纳米复合材料 .通过改变累托石含量发现在很低含量 (0 5W % )时纳米复合材料具有最佳力学和热学性能 ,冲击强度增加 12 0 % ,断裂伸长率增加 330 %玻璃化转变温度提高 2 8℃ .用X衍射、透射电镜和红外吸收光谱研究了材料的微观结构 ,结果表明层状累托石和环氧树脂发生了化学反应 ,观测到了层状累托石完全剥离和插层两种结构形态 ,且累托石含量较低时容易形成剥离型 .具有大的比表面积、高的反应活性的累托石片层分散于环氧基体中形成剥离型为主的结构有利于改善复合材料的力学性能并增加其热稳定性 . 相似文献
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通过对累托石和氧化钛交联累托石的离子交换和吸附性能研究,得出氧化钛交联累托石具有良好的离子交换和吸附特性,对NH_4 ̄+、K+和NH3在中性水溶液中有特征吸附,分别较原矿高出156%、70%和262%,阳离子吸附性能随交换液的PH值升高而增大。 相似文献
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DU Dongyun LI Dunshun YU Zhongshan Key Laboratory of Catalysis Material Science of Hubei Province College of Chemistry Material Science South-Central University for Nationalities Wuhan China Department of Chemistry Environmental Engineering Hubei Normal University Huangshi China Daye Non-ferrous Metals Company Limitted Huangshi China 《Chinese Journal of Reactive Polymers》2005,(Z1)
1. INTRODUCTION In recent years, water body eutrophication has become a serious problem. Eutrophication is caused mainly by growth of aquatic plants that are stimulated by dissolved nutrients such as phosphates. Concentrations of TN and TP over the level of cleaning-itself are major indicators for water body eutrophication [1,2]. The presence of trace amounts of phosphate (even less than one ppm) in treated waste water from municipalities and industries is often responsible for eutrophic… 相似文献
10.
The presence of trace phosphates in treated wastewater from municipalities and industries is often responsible for eutrophication problems in lakes, rivers, and other water bodies. In this paper,we report the removal of PO43- from water by using a pillared rectorite that we synthesized recently. The results show that cross-linking can significantly increase the adsorbing capacity of Na-rectorite for phosphates. The pH, the concentrations of F, NH4+ and COD are main factors, which affect the results for pillared rectorite to adsorb phosphates from water. The OH-, and F- ions decrease the capacity to adsorb phosphates, while the COD and NH4+ ions increase it. 相似文献