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硅烷偶联剂对纳米二氧化钛表面改性的研究 总被引:40,自引:0,他引:40
利用硅烷偶联剂(KH-570)对表面包覆氧化硅的金红石相纳米TiO2进行了有机表面改性.采用红外光谱(IR)、X射线光电子能谱(XPS)、热分析(TG-DTA)、透射电镜(TEM)和润湿性实验等分析手段对表面改性前后的纳米TiO2进行了表征.红外光谱和X射线光电子能谱表明,KH-570以化学键合的方式结合在纳米TiO2的表面,并形成了有机包覆层.经测量,纳米TiO2表面包覆的KH-570的质量分数约为7.42%-8.59%.润湿性实验显示,经KH-570表面改性的纳米TiO2具有疏水性.力学性能实验表明,经KH-570表面改性的纳米TiO2能同时提高复合材料的强度和韧性. 相似文献
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采用十二胺对氧化石墨片进行表面改性,通过红外光谱(FT-IR)、X射线衍射(XRD)和核磁共振谱(NMR)对改性后的氧化石墨片(GO-DDA)结构进行表征。将GO-DDA引入氰酸酯树脂体系,制备了氰酸酯(CE)/氧化石墨片复合材料,着重研究了GO-DDA用量对氰酸酯固化反应及复合材料导热与绝缘性能的影响。DSC结果表明,GO-DDA对氰酸酯树脂固化反应有明显的促进作用,可降低树脂的固化温度。复合材料的热导率和体积电阻率测试结果表明,GO-DDA的加入能显著提高氰酸酯树脂的导热性能,当GO-DDA加入量为1.0%时,复合材料的热导率比纯CE树脂材料提高了48%,而且复合材料仍具有良好的电绝缘性能。复合材料的SEM结果表明,少量GO-DDA的加入还有利于改善复合材料的断裂韧性。 相似文献
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2-氨基乙基-二(3-氨基丙基)胺的合成工艺研究 总被引:9,自引:0,他引:9
利用氨基乙腈及丙烯腈的亲核加成、氢化反应合成了一种新的不等臂有机多胺化合物 2 -氨基乙基 -二 (3-氨基丙基 )胺。研究了不同工艺条件对反应的影响 ,最佳工艺条件为 :n(丙烯腈 )∶n(氨基乙腈 ) =2 .8~ 3 .0 ,加成温度为 70~ 75℃ ,加成反应时间为 50~ 60h ,催化反应采用复合催化剂 ,m(溶剂 )∶m(物料 )≈ 1 0。两步反应的收率分别为 81 .6 %和 71 .6 % ,用多种谱学手段表征确证了该化合物及其中间产物 相似文献
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Attapulgite fibers were modified by polyurethane, forming polyurethane grafted attapulgite (AT-PU), which was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Nylon 6/AT-PU nanocomposites of different modified attapulgite loadings were prepared by melt blending in a twin screw extruder. Scanning electron microscopy (SEM) observation on the fracture surfaces of the nanocomposites showed not only a uniform dispersion of AT-PU but ... 相似文献
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A facile approach to preparing well-dispersed nanocrystals of BaCeO3 was developed by a combination of solvothermal and annealing processes. The precursor consisted of amorphous BaCO3 and CeO2, and the conversion of the precursor to crystalline BafeO3 nanocrystals occurred upon heat treatment at a relatively low temperature. The as-processed BaCeO3 had an orthorhombic structure and the average size of such crystals was approximately 80 nm. The obtained products were characterized by Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Laser Raman Spectroscopy (LRS), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectrometry (EDS), and Transmission Electron Microscopy (TEM). This preparation process could also be used to synthesize doped barium cerate complex oxides Bafe0.95M0.05O3-δ (M=Y, Nd, Gd, and Sm). 相似文献