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无机纳米杂化聚酰亚胺薄膜的研究进展 总被引:4,自引:3,他引:1
无机纳米杂化聚酰亚胺复合薄膜因无机填料在聚合物基体中纳米尺度的分散以及与基体间强的化学结合而具有较常规聚酰亚胺薄膜材料更优异的力学性能、热稳定性能、高绝缘性能及耐电晕性能等.依据国内外聚酰亚胺纳米杂化薄膜材料的最新研究情况,重点综述了SiO2/Al2O3、SiO2/Ti2O3、SiO2、TiO2、Al2O3、SiC、MMT等纳米杂化聚酰亚胺薄膜的研究进展,表明其是一种性能优异、具有广泛应用前途的有机一无机纳米复合材料,但尚存在许多需进一步深入研究的问题. 相似文献
84.
Kumar Sai SMARAN Rajashekar BADAM Raman VEDARAJAN Noriyoshi MATSUMI 《Frontiers in Energy》2019,13(1):163
This paper focuses on the superiority of organic-inorganic hybrid ion-gel electrolytes for lithium-ion batteries (LiBs) over commercial electrolytes, such as 1 M LiPF6 in 1:1 ethylene carbonate (EC): dimethyl carbonate (DMC) {1 M LiPF6-EC: DMC}, in terms of their flame susceptibility. These ion-gel electrolytes possess ionic liquid monomers, which are confined within the borosilicate or silicate matrices that are ideal for non-flammability. Naked flame tests confirm that the organic-inorganic hybrid electrolytes are less susceptible to flames, and these electrolytes do not suffer from a major loss in terms of weight. In addition, the hybrids are self-extinguishable. Therefore, these hybrids are only oxidized when subjected to a flame unlike other commercial electrolytes used in lithium-ion batteries. Supplementary analyses using differential scanning calorimetric studies reveal that the hybrids are glassy until the temperature reaches more than 100°C. The current results are consistent with previously published data on the organic-inorganic hybrids. 相似文献
85.
To avoid the negative effect of graphene oxide (GO) nanosheets aggregation in aqueous solutions on physicochemical properties of GO incorporated nanocomposite hydrogels, poly(vinyl alcohol)-functionalized GO (GO-es-PVA) are synthesized and are used for preparation of nanocomposite hydrogels. By graft copolymerization of GO-es-PVA with poly(AA-co-AAm) chains, the nanocomposite hydrogel samples with covalently incorporated GO-es-PVA are achieved. FTIR spectroscopy, XRD analysis, and SEM and EDAX techniques confirm successful synthesis process. It is clear that GO-es-PVA content has significant effect on physicochemical properties of nanocomposite hydrogels, such as improvement of the water uptake properties, porosity, and gel strength. The hydrogel sample with 1:80 mass ratio of GO-es-PVA/AAm has the best physicochemical properties due to the optimum amount of GO-es-PVA, which gives the hydrogel proper viscoelasticity as well as fine porosity and water uptake rate. Interpenetration of PVA chains into the polymeric networks makes the movement of the polymer chains easier, which leads to softer polymeric networks. This phenomenon is called plasticizing effect. The plasticizing nature of PVA and its high hydrophilicity are the main reasons for the fine physicochemical properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48025. 相似文献
86.
以1,2-二(三乙氧基硅基)乙烷(BTESE)为前驱体、PdCl2为钯源, 制备Pd掺杂有机无机杂化SiO2(POS)溶胶, 涂膜后在水蒸气氛围中煅烧, 制备得到POS膜。采用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、N2吸附-脱附和透射电子显微镜(TEM)对POS粉体的微观结构进行表征。考察了钯/硅摩尔比(n(Pd/Si)=0.1、0.5和1)对POS膜的气体分离性能与水热稳定性能的影响。结果表明: 随着Pd掺杂量的增加, POS膜的H2渗透率逐渐增大, H2/CO2的理想选择性逐渐下降。经100 kPa水蒸气处理180 h后, 采用n (Pd/Si)=1制备的POS膜的H2渗透率达到1.62× 10-7 mol·m-2·s-1·Pa-1, H2/CO2理想分离因子达到13.6, 表明该膜具有较好的H2渗透性能、H2/CO2分离性能和水热稳定性能。 相似文献
87.
热电材料可以实现热能与电能的直接转化,是一种安全环保的新型能源材料。近年来,随着可穿戴电子设备的发展,柔性热电材料成为研究人员关注的焦点。传统无机热电材料具有优异的热电性能,但由于自身固有的脆性,限制了在柔性领域的发展。聚3, 4-乙烯二氧噻吩: 聚苯乙烯磺酸盐(PEDOT: PSS)具有高电导率、低热导率和良好的柔性,在柔性热电领域具有巨大的潜力。当选择合适的无机填料与PEDOT: PSS进行复合,可以得到优异的热电性能和良好的力学性能。本文综述了PEDOT: PSS基纳米复合薄膜的最新进展,并详细介绍了提高PEDOT: PSS基纳米复合薄膜热电性能的有效方法。最后,本文总结了实现高性能PEDOT: PSS基柔性热电材料的途径及面对的挑战。 相似文献
88.
Jiabei Yuan Xuliang Zhang Jianguo Sun Robert Patterson Huifeng Yao Di Xue Yao Wang Kang Ji Long Hu Shujuan Huang Dewei Chu Tom Wu Jianhui Hou Jianyu Yuan 《Advanced functional materials》2021,31(27):2101272
Organic-inorganic hybrid film using conjugated materials and quantum dots (QDs) are of great interest for solution-processed optoelectronic devices, including photovoltaics (PVs). However, it is still challenging to fabricate conductive hybrid films to maximize their PV performance. Herein, for the first time, superior PV performance of hybrid solar cells consisting of CsPbI3 perovskite QDs and Y6 series non-fullerene molecules is demonstrated and further highlights their importance on hybrid device design. In specific, a hybrid active layer is developed using CsPbI3 QDs and non-fullerene molecules, enabling a type-II energy alignment for efficient charge transfer and extraction. Additionally, the non-fullerene molecules can well passivate the QDs, reducing surface defects and energetic disorder. The champion CsPbI3 QD/Y6-F hybrid device has a record-high efficiency of 15.05% for QD/organic hybrid PV devices, paving a new way to construct solution-processable hybrid film for efficient optoelectronic devices. 相似文献
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90.
聚酰胺6/凹凸棒土纳米复合材料的制备与性能 总被引:3,自引:0,他引:3
采用双螺杆挤出机将凹凸棒土与聚酰胺6共混,制备聚酰胺6/凹凸棒土纳米复合材料,考察了凹凸棒土活化前后对聚酰胺6力学性能、微观形态、结晶行为的影响,结果表明:凹凸棒土以纳米尺寸分散于复合材料中;凹凸棒土的加入,可以促进聚酰胺6结晶;与未经硅烷偶联剂活化的凹凸棒土相比,活化后凹凸棒土的加入,可以提高复合材料的拉伸强度、冲击强度,经过硅烷偶联剂处理的凹凸棒土可以用于改性聚酰胺6。 相似文献