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101.
102.
热解除油是目前室内岩心分析中样品除油的主要方法之一,但由于热解温度较高,会对样品中粘土矿物的结构水和层间水产生较大的影响。本文结合粘土矿物的吸水特性,通过对大量的实验测定结果分析后认为:经过热解处理后的样品,在测定过程中受粘土矿物(主要是伊利石和蒙脱石)层间水变化的影响,会引起样品重量及样品孔隙空间体积的变化,从而对物性分析中孔隙度测定结果产生较大的影响。  相似文献   
103.
本文分别对锌蒙脱石隔离层与传统糊式隔离层的电导性能与循环伏安特性进行了比较。结果表明:锌蒙脱石隔离层可代替糊式隔离层用于干电池生产。  相似文献   
104.
H.A. Stretz  P.E. Cassidy 《Polymer》2005,46(11):3818-3830
Dispersion of clay particles in acrylonitrile-butadiene-styrene (ABS) and styrene-acrylonitrile copolymer (SAN) nanocomposites with montmorillonite (MMT) have been compared to assess whether ABS/MMT nanocomposite behavior can be adequately modeled using the simpler SAN/MMT system. Electron microscopy photomicrographs show that clay particles in ABS/MMT composites reside in the SAN matrix phase and accumulate at the rubber particle surfaces. In mixtures of four organoclays with the two polymers, WAXS (wide angle X-ray scattering) peak height and shift in gallery height was the same for a given organoclay. Aspect ratios determined through image analysis were also the same in each polymer. Modulus enhancement as measured by an exfoliation efficiency index showed the same patterns for each organoclay in the two matrices, but the ABS/MMT composites had consistently lower efficiencies than in SAN/MMT composites. This trend is expected to be due to the variations in orientation of clay particles in ABS/MMT composites at the rubber particle surface. In summary, SAN/MMT composites represent a good model system for ABS/MMT.  相似文献   
105.
The photo-oxidative behavior of the polypropylene (PP)/montmorillonite (MMT) nanocomposites and microcomposites has been investigated upon ultraviolet exposure using the technique of infrared spectroscopy. The rate of photo-oxidative degradation of PP/MMT nanocomposites is much faster than that of pure PP. The influence of pristine MMT, alkylammonium and compatibilizer were investigated, respectively. All these components can catalyze the photo-oxidation of PP matrix, in which the influence of compatibilizer and pristine MMT is primary. Moreover, the dispersion state of the clay particles in the polymer matrices has a little influence on the photo-oxidative degradation of polymer matrix. Consequently, an integrated catalysis mechanism of the photo-oxidative degradation of PP clay nanocomposite is proposed. It would provide benefit direction for the preparation and usage of polymer layered silicate nanocomposites (PLSN).  相似文献   
106.
微波法制备有机蒙脱土及其结构表征   总被引:4,自引:0,他引:4  
采用钠基蒙脱土、十六烷基三甲基溴化胺为原料,通过微波辐射制备了有机蒙脱土,并用红外光谱分析(IR)、热重分析(TGA)和X-射线衍射分析(XRD)对其结构进行了表征。  相似文献   
107.
Diglycidyl ether of bisphenol A type epoxy resin-polyether polyol-organically treated montmorillonite ternary nanocomposites were synthesized in this study. The effects of addition of polyether polyol as an impact modifier on morphological, thermal and mechanical properties of nanocomposites were investigated by X-ray diffraction, scanning electron microscopy (SEM), differential scanning calorimetry, impact and tensile testing. The results showed that organically treated montmorillonite is intercalated by epoxy, since the interlayer spacing expanded from 1.83 to 3.82 nm upon nanocomposite synthesis. The addition of polyether polyol impact modifier had no effect on the interlayer spacing. SEM examination showed that polyol forms an immiscible phase in the epoxy matrix. Thermal characterization of nanocomposites indicated an increase in Tg with respect to both polyether polyol and montmorillonite contents. The impact strength of the samples with no clay was improved approximately 160% upon adding 7 wt% polyether polyol. In polyether polyol modified nanocomposites, the impact and tensile strengths decreased with respect to increasing amount of montmorillonite and showed a maximum with respect to the polyether polyol content at constant clay loading. The Young's modulus of the nanocomposites exhibited an increase with respect to the montmorillonite loading and showed a maximum with respect to the polyol content at each clay loading.  相似文献   
108.
ABSTRACT

A new nanocomposite coating was synthesized by MMT and polyurethane for controlled-release fertilizers (CRFs). The structure and properties of samples were characterized. The nutrient release behavior of nanocomposite-coated fertilizers (MPUs) and polyurethane-coated fertilizers (PU) in water and in soil were determined. SEM and TEM exhibited good dispersion of MMT lamellae in the MPU coatings. The results also showed that the water contact angle of the MPU coating was greatly improved, the water absorption was reduced by 65.7%, and the coating porosity was reduced by 30.0%. In addition, MPUs exhibited longer nutrient release longevity than that of PU (26 days), especially MPU with 5% MMT (90 days). Therefore, MPUs with excellent properties can provide information for the development of CRFs.  相似文献   
109.
聚苯乙烯/蒙脱土纳米复合材料的制备与表征   总被引:3,自引:0,他引:3  
用十二烷基硫酸钠对钠基蒙脱土进行有机改性,将其层间距打开。用FT—IR和XRD进行表征。结果表明:有机插层剂已插层进入蒙脱土层间,然后利用乳液聚合法制备了聚苯乙烯/蒙脱土纳米复合材料。DTA和TGA分析表明:与纯聚苯乙烯相比,所得聚苯乙烯/蒙脱土(PS/MMT)纳米复合材料的热性能得到提高。  相似文献   
110.
插层复合法制备纳米塑料的研究进展   总被引:1,自引:0,他引:1  
介绍了纳米塑料的插层复合制备原理及工艺过程,对纳米塑料的研究进展和应用情况作了综述。  相似文献   
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