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171.
Jinhong Kim Junho Jang Sehui Yun Hyeon Deok Kim You Young Byun Yong Tae Park Jung Il Song Chungyeon Cho 《大分子材料与工程》2021,306(9):2100233
In an effort to develop highly functionalized flame retardant materials, hybrid nanocoatings are prepared by alternately depositing a positively charged polyaniline (PANi) and negatively charged montmorillonite (MMT) using the layer-by-layer (LbL) assembly technique. Carbon nanotubes (CNTs) are employed in polymer nanocomposites as effective reinforcement, where nanotubes are stabilized in MMT aqueous solution. The 3D structure and high density of CNTs deposited in the PANi/CNTs-MMT multilayers produce thicker and heavier coatings in comparison to the LbL assemblies without CNTs. Vertical and horizontal flame testing show that the incorporation of CNTs improves fire resistance. Additionally, cone calorimetry reveals that stacking two nanomaterials (MMT and CNTs) in a single coating shows a significant reduction in peak heat release rate (up to 51%), total smoke release (up to 47%), and total heat release (up to 37%) for the polyurethane foam. The enhancement of flame retardancy is attributed to a synergistic effect; MMT serves as a physical barrier that retards the diffusion of heat and gas. The addition of CNTs strengthens the thermal stability and high char yield. These results, coupled with the simplicity with which the LbL deposition is applied, present a viable alternative to halogen-free flame retardant nanocoatings to natural and synthetic fibers. 相似文献
172.
Asok Aparna A. S Sethulekshmi Jitha S. Jayan Appukuttan Saritha Kuruvilla Joseph 《大分子材料与工程》2021,306(11):2100429
Boron nitride (BN) is an eminent inorganic compound having many interesting characteristics such as improved oxidation resistance, mechanical strength, good thermal conductivity (TC), higher bandgap, high chemical stability, thermal stability, high hydrophobicity, and electrical insulation. The use of BN as a filler in polymers is a well-established strategy to tailor the properties of polymer composites. Recent studies depict an interesting urge to reap the synergistic effect of various nanofillers with BN in the form of hybrids. Hence the consolidation of the works on BN based hybrid fillers would definitely attract researchers so that these new filler systems could be transformed into useful polymer nanocomposites in future. This review article focuses on the synthesis and characterization of various boron nitride based hybrids in detail. Moreover, the review also throws light on different BN hybrid reinforced polymer nanocomposites (PNCs) and their thermal, electrical, electronic as well as biomedical applications in a detailed manner. Thus the review anticipates serving as a tool toward understanding the recent trends in the field of boron nitride hybrid based ternary polymer composites. 相似文献
173.
Alexander Zimmermann Qais Z. Jaber Dr. Johannes Koch Steffen Riebe Dr. Cecilia Vallet Dr. Kateryna Loza Matthias Hayduk Dr. Kfir B. Steinbuch Prof. Shirley K. Knauer Prof. Micha Fridman Jun.-Prof. Jens Voskuhl 《Chembiochem : a European journal of chemical biology》2021,22(9):1563-1567
We report the characterization of amphiphilic aminoglycoside conjugates containing luminophores with aggregation-induced emission properties as transfection reagents. These inherently luminescent transfection vectors are capable of binding plasmid DNA through electrostatic interactions; this binding results in an emission “on” signal due to restriction of intramolecular motion of the luminophore core. The luminescent cationic amphiphiles effectively transferred plasmid DNA into mammalian cells (HeLa, HEK 293T), as proven by expression of a red fluorescent protein marker. The morphologies of the aggregates were investigated by microscopy as well as ζ-potential and dynamic light-scattering measurements. The transfection efficiencies using luminescent cationic amphiphiles were similar to that of the gold-standard transfection reagent Lipofectamine® 2000. 相似文献
174.
1 INTRODUCTIONWorldwide research and efforts are currentlyunderway to fabricate all solid state, rechargeableLi and Li ion batteries utilizing Li+ conductivepolymer electrolytes[1]. Solid polymer electrolytespossesses many advantages including high ionicconductivity, high specific surface energy, solventfree, wide electrochemical stability windows, lightand easy processability[2]. Apart from polyethy lene oxide ( PEO )[3], poly ( vinyl alcohol )(PAV)[4], … 相似文献
175.
利用钢丝探头分别测量了含碳0.70%的钢丝在铅浴和CMC水溶液中的冷却过程。用冷却曲线分析法阐释了钢丝的冷却过程和相变规律。钢丝的“体积效应”和在其冷却介质中的热扩散能力共同决定了铅浴淬火过程及钢丝的相变过程。高碳钢钢丝在0.25%CMC水溶液中可完全转变为珠光体组织,但其转变温度由于其连续冷却转变特性而高于在铅浴中的转变温度。根据铅浴淬火的冷却本质和CMC水溶液的冷却特性,用于替代铅浴的淬火介质应设法加快初始阶段冷却速率。 相似文献
176.
酪素/蒙脱土插层复合物制备及其耐水性能研究 总被引:3,自引:1,他引:3
在十六烷基季胺盐存在下进行蒙脱土插层得到[H4N(CH2)15CH3]+-蒙脱土插层物,酪素加热溶解后与[H4N(CH2)15CH]+-蒙脱土插层物混合,保温复合,然后沉淀分离,得到干酪素/蒙脱土纳米复合物。用XRD,TEM和TGA表征酪素纳米复合物的结构与性能。结果表明,插层复合物中蒙脱土晶片间距扩大,插层复合物耐热性能明显提高,与纯酪素相比,复合物拥有极好的耐水性能,特别适用于制备高速高性能啤酒生产线用贴标胶。 相似文献
177.
178.
Shalu Kataria Yogendra L. Verma Himani Gupta Shishir K. Singh Nitin Srivastava Ravindra Dhar 《Polymer-Plastics Technology and Engineering》2020,59(9):952-958
ABSTRACTNano-composite polymer gel electrolytes (NPGEs) based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3- methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI, Li-salt along with the addition of SiO2 nanoparticles have been synthesized and characterized by various techniques. Prepared NPGEs show high room temperature ionic conductivity (~10?3 S/cm) and have a wide electrochemical window (ECW) (~3.3–3.5 V). The galvanostatic charge/discharge profile was studied by sandwiching best performing NPGEs between a LiFePO4 cathode and lithium metal anode. The specific discharge capacity of the cell (Li/NPGE/LiFePO4) room temperature at 0.1C rate is found to be 138 mAh/g. 相似文献
179.
低翘曲玻纤增强PET复合材料的制备和性能研究 总被引:4,自引:0,他引:4
依据降低翘曲的机理,选用不同降低翘曲的方法,制备了系列翘曲玻纤增强PET复合材料,结果表明,具有较高形状对称性的填料,如滑石粉,云母粉和玻璃微珠都能不同程度地降低玻纤增强PET体系的翘曲,非晶聚合物也能有效改进该体系的翘曲性能。 相似文献
180.
聚铝溶液pH值及盐基度的相关性研究 总被引:6,自引:1,他引:6
为聚铝溶液进行了PH值和盐基度的分析和估算,给出了聚铝溶液的极限PH值和极限盐基度与总溶解铝浓度的关系曲线,最终计算结果表明:在平衡条件下,聚铝溶液的PH值和盐基度具有相关性,即当基中一个参数发生变化时。另一个参数必然要发生相应的改变。 相似文献