共查询到17条相似文献,搜索用时 98 毫秒
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以高岭石-甲醇(K-M)复合物为前驱体,利用置换法于常温下制备了3种高岭石-氨基硅烷插层复合物。用X射线衍射、Fourier变换红外光谱仪、透射电子显微镜、热分析仪等对复合物进行了表征。结果表明:3种高岭石-氨基硅烷插层复合物的层间距均扩大至2nm以上,插层率都大于95%。3种氨基硅烷分子均和K-M前驱体的甲氧基共同存在于高岭石层间,均呈两层倾斜排列,倾斜程度不同。氨基硅烷的插入破坏了高岭石层间的氢键,加剧了高岭石自身结构中硅氧四面体片层与铝氧八面体片层之间的错位,使得复合物片层出现不同程度的卷曲变形。3种高岭石-氨基硅烷插层复合物的热分解过程均分三步进行:表面水的蒸发及层间甲氧基的脱嵌分解、插层剂氨基硅烷分子的脱嵌、高岭石脱羟基。 相似文献
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介绍了二甲亚砜(DMSO)取代法制备高岭石/酒石酸(标记为K/T)插层复合物.产物经XRD-6000粉晶衍射和傅立叶变换红外光谱表征.XRD表明:高岭石层间距由0.72 nm扩张到1.09 nm,插层率达50%.红外光谱表明:酒石酸分子的羰基与高岭石的内表面羟基形成了氢键,而羟基与高岭石的硅氧面的氧形成了氢键.酒石酸分子以单分子层平铺于高岭石层间. 相似文献
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分别以高岭石--二甲基亚砜插层复合物和高岭石--尿素插层复合物为前驱体,采用多次逐步置换插层方法制备高岭石--甲醇插层复合物。通过X射线衍射和红外光谱测定不同插层阶段产物的结构,对不同前驱体制备高岭石--甲醇插层复合物的置换插层机理进行了探讨。结果表明:前驱体不同,其置换过程行为不一样。以高岭石--二甲基亚砜插层复合物为前驱体,甲醇分子首先以分子状态进入层间,随着置换次数和时间的增长,逐渐以化学键结合于层间,表现为变化较大的层间距;以高岭石--尿素插层复合物为前驱体,甲醇分子直接以化学键结合于层间,表现为比较稳定的层间距。红外光谱研究表明甲醇分子主要与高岭石晶层中的内表面羟基发生作用,形成新的化学键接枝于高岭石层间。 相似文献
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采用多次置换插层法制得高岭石-甲醇插层复合物,用X射线衍射、傅里叶变换红外光谱、热重和差示扫描量热技术对产物的结构和热分解行为进行了表征.结果表明:甲醇插入到高岭石层间,高岭石层间距由0.71 nm扩大到0.93 nm,插层率为100%.插层复合物中,甲醇分别以与高岭石内表面范德华力结合、氢键键合及嵌入复三方孔穴三种形态存在.在加热过程中,插层复合物分三步分解.第一步分解发生于30~120℃,为层间范德华力结合的甲醇分子的脱嵌过程;第二步发生于120~350℃,是氢键键合的甲醇的脱嵌过程;第三步发生在400~ 600℃,对应于高岭石脱羟基和嵌入高岭石晶格内部的甲醇的脱嵌过程.计算得到复合物体系中高岭石与甲醇的分子摩尔比为1∶0.7,其中以范德华力结合、氢键键合和嵌入复三方孔穴的甲醇的摩尔比为5.2∶11.8∶1. 相似文献
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《中国陶瓷》2010,(8)
以高岭石/二甲基亚砜插层复合物作为前驱体,采用二次取代法制备了高岭石/咪唑插层复合物,采用X-射线衍射、红外光谱、激光粒度分析等技术对产物进行表征。实验结果表明:咪唑已成功插入到高岭石中。XRD分析表明:在高岭石/咪唑插层复合物中,高岭石的层间距由0.72nm扩张到1.125nm,插层率达到了71.7%,红外光谱研究表明,插层中咪唑分子中的N-H基与高岭石内表面羟基之间产生了N-H-OH作用,形成了新的氢键;热重-差热曲线(TG-DTA)分析表明:高岭石/咪唑插层复合物在130~220℃的温度范围内,会发生咪唑的脱嵌过程,粒度分析表明:高岭石粒径小于5μm的颗粒占总颗粒数的比例降低了12.66%。 相似文献
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高岭石/聚苯乙烯插层复合物碳热还原反应制备碳化硅晶须/氧化铝复相陶瓷粉体 总被引:3,自引:1,他引:2
以二甲基亚砜(dimethylsuIfox.de,DMSO)为插层剂制得高岭石/DMSO插层复合物,将苯乙烯单体与高岭石,DMSO插层复合物进行置换反应, 成功地将苯乙烯单体引入高岭石层间,层间苯乙烯在加热条件下聚合,制得高岭石/聚苯已烯捅层复合物.以高岭石/聚苯乙烯插层复合物为原料,在氩气保护气氛下,于1500℃碳热还原反应制备碳化硅晶须/氧化铝(SiCw/Al2O3)复相陶瓷粉体.结果表明:在高岭石/聚苯乙烯插层复合物中,高岭石 的层间距由0.717nm扩张到1.130nm,插层率接近100%.插层作用影响了层间羟基基团的振动,使其键合方式发生改变.X射线衍射和扫描电镜分 析表明:合成出SiCw/Al2O3复相陶瓷粉体中SiC和Al2O3为主品相,SiC呈晶须状,其直径≤200nm,长度≥3μm. 相似文献
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高岭石及其有机插层复合物在高性能陶瓷领域有着良好的应用前景。本文利用微波技术,以DMSO作为前驱体,制备高岭石/丙烯酰胺插层复合物,发现微波对丙稀酰胺的插层反应具有相当明显的促进作用,反应时间从通常的几天缩短到几个小时。采用X-射线衍射、FT-IR光谱、TG等技术对其进行表征。结果表明:反应2小时后,该插层复合物的层间距即可扩大为1.139nm,其键合方式发生了改变,形成新的氢键。这为工业生产高岭石有机插层物以及制造纳米级高岭土提供了高效的新途径,并为进一步生产高性能陶瓷方面打下了基础。 相似文献
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Intercalate nanomaterial comprising of ionic liquid 1-butyl-3-methylimidazolium bromine [bmim]Br and methanol-pretreated kaolinite was prepared. We study several physical properties of the new intercalation compound by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Thermogravimetric analysis and differential scanning calorimetry (TG–DSC), UV–vis spectra and scanning electron microscopy (SEM). The intercalation compound shows an increase of the basal spacing from 0.72 nm (for kaolinite) to 1.42 nm (for the material with the guest). Intercalated compound shows an increase in the thermal stability. Finally, the UV–vis spectra reveal significant absorption in the UV region for this inclusion compound. 相似文献
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高岭石有机插层反应的影响因素 总被引:24,自引:0,他引:24
利用高岭石的层状结构特征,将有机分子插入高岭石层间形成的高岭石有机复合物,兼具粘土矿物和有机物的特性,是一种新型矿物材料,在功能填料、陶瓷材料、催化剂、择吸附剂、环境修复材料等方面具有广泛的应用前景。高岭石层间氢键作用较强,有机分子的插层作用比较困难,合理控制插层条件是插层作用完成的关键。评述了高岭石特征、插层有机分子性质、水、温度、压力、PH值等因素对高岭石有机插层作用的影响。 相似文献
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In this study, intercalation of dimethylsulphoxide (DMSO) in a Cameroonian kaolinite is used to achieve weakening of the interlayer hydrogen bonds, in the perspective of dispersion or even exfoliation of the clay within polymer composite materials. Displacement of intercalated DMSO by ethyl acetate and ammonium acetate is studied in order to simulate the interactions with the polymer matrix. The exfoliation of the kaolinite is well evidenced by X-ray diffraction and SEM observations. The disruption of the interlayer bonds is shown by the displacement of the FT-IR vibration modes of both Al–OH and Si–O functions, and by the decrease of the dehydroxylation temperature recorded by Controlled Rate Thermal Analysis. Complete displacement of DMSO by ethyl acetate is achieved and the crystalline structure is deeply disordered as a result of interlayer bonds weakening. The displacement of DMSO by ammonium acetate leads to a ternary composite of DMSO/ammonium acetate with respective intercalation ratio of 62.4% and 57.7%. 相似文献
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The surface modification of kaolinite to introduce the adsorption sites for anionic species was reported. The introduction
of an anion exchange site was as follows; intercalation of 2-aminoethanol into kaolinite by using dimethyl sulfoxide-kaolinite
intercalation compound as a precursor and subsequent hydrochlorination of 2-aminoethanol-kaolinite in 1,4-dioxane. The hydrochlorination
of 2-aminoethanol-kaolinite was confirmed by the increase in the basal spacing (0.2 nm, corresponding to the diameter of chlorine)
and the appearance of the infrared absorption bands due to ammonium groups. The modified kaolinite adsorbed an anionic dye,
tetrakis(p-sulfonatophenyl)porphyrin, from a N,N-dimethylformamide solution. Initial slope of the adsorption isotherm of tetrakis(p-sulfonatophenyl)porphyrin on the hydrochlorinated 2-aminoethanol-kaolinite was steep, showing strong adsorbate-adsorbent
interactions. The gallery height after the adsorption of tetrakis(p-sulfonatophenyl)porphyrin was close to the thickness of the porphyrin ring, suggesting that tetrakis(p-sulfonatophenyl)porphyrin was intercalated as a monomolecular layer and that chlorine simultaneously deintercalated. 相似文献
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硬脂酸/埃洛石插层复合相变材料的制备及其性能研究 总被引:1,自引:0,他引:1
用二甲基亚砜取代法制备了硬脂酸/埃洛石插层复合相变材料.借助于X射线衍射、综合热分析、红外光谱和扫描电子显微镜等方法分析了复合相变材料的插层效果、插层机理及热性能.结果表明:硬脂酸/埃洛石插层复合物中,埃洛石的层间距由0.74 nm增大到3.92 nm,插层率达到了95.4%,埃洛石的内表面羟基与硬脂酸的羰基形成了氢键... 相似文献
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Complete urea-intercalation of a low reactivity kaolinite from Birdwood has been carried out by co-grinding with urea in the absence of water (mechanochemical intercalation). The effectiveness of mechanochemical intercalation was compared to solution intercalation by X-ray diffraction (XRD), thermal analysis (TG, DTG), diffuse reflectance Fourier transform infrared (DRIFT) spectroscopy and scanning electron microscopy (SEM). In aqueous solution of urea the Birdwood kaolinite was intercalated with difficulty and only 12% intercalation was achieved. After 2 h of co-grinding with solid urea, complete (100%) intercalation was attained. The possible explanation of complete intercalation is that co-grinding of Birdwood kaolin with solid urea can remove the high-defect kaolinite coating, which prevents the intercalation of the low-defect kaolinite particles. The mechanochemical treatment increased the degree of intercalation and in parallel reduced the amount of the crystalline kaolinite phase. 相似文献