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1.
采用溶胶-凝胶法,首先利用苯乙烯与3-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)化学反应合成共聚前驱物,利用TEOS在一定的条件下水解与缩合,一步合成了有机-无机复合纳米微球。用扫描电镜、红外光谱对共聚物及复合纳米粒子进行了表征。将非水溶性发光材料四苯基卟啉掺杂其中,制备出荧光复合纳米粒子。该粒子表现出了良好的发光性能,染料泄漏与猝灭几乎为零,可以作为一种新型的高效率的生物标记材料。  相似文献   

2.
超细金属铁颗粒的高分子修饰及其悬浮液的磁流变性能   总被引:2,自引:0,他引:2  
报道了γ射线辐照方法合成具有良好分散性的高分子复合金属铁粒子,分别选择十二烷基硫酸钠、溴化十六锘三甲基胺、Tween-80、TritonX-200和OP-10表面活必睡有机单体、无机铁颗粒一起制备乳状液,通过对这种含有超细金属铁颗粒乳状液稳定性的比较,以寻求合适的乳化剂,并对以TritonX-200为乳化剂时合成出的高聚物复合铁颗进行了XRD、TEM和IR表征,还将实验中所获得的高聚物复合铁粒子与  相似文献   

3.
纳米ZnO的表面化学修饰及其分析表征   总被引:7,自引:0,他引:7  
采用水溶性羟丙基甲基纤维素HPMC对无机纳米ZnO粒子进行物理吸附处理 ,获得了核为无机纳米ZnO ,外壳为水溶性高分子HPMC的粒子。然后在其上进行了甲基丙烯酸甲酯的接枝聚合。采用红外光谱、差热分析的方法对复合粒子进行了表征 ,并采用透射电镜观察了粒子的形貌。红外光谱表明在纳米ZnO的表面吸附了HPMC并接枝了PMMA ,差热分析表明HPMC ,HPMC g PMMA和ZnO/HPMC g PMMA的热稳定性逐渐提高 ,透射电镜观察表明 ,在纳米ZnO的表面粘附了一层聚合物 ,成功地实现了纳米粒子的表面修饰。  相似文献   

4.
研究无机纳米掺杂有机复合薄膜力学性能、热学性能、电学性能变化规律的关键在于快速、准确地掌握复合膜中纳米无机物的掺入量及其颗粒大小和分布状态。文章通过X射线荧光光谱、红外光谱、扫描电子显微镜、原子力显微镜等测试方法对无机纳米氧化铝/聚酰亚胺复合薄膜的三氧化二铝掺入量、化学结构及表面形貌进行了表征分析(该材料为本研究室制备的)。结果表明:聚酰亚胺有机相与三氧化二铝无机相之间形成了键联型复合杂化体系;三氧化二铝粒子呈纳米级均匀地分散在聚酰亚胺基体中,颗粒直径均在50nm以下;利用X射线荧光光谱法测定出三氧化二铝的质量含量为7·9%,利用该方法定性、定量分析无机纳米掺杂有机复合薄膜材料中的无机组分具有样品不需要预处理、不需要加载电荷(可用于分析绝缘材料)、非接触性、非破坏性、速度快、准确度高等优点。  相似文献   

5.
具有超顺磁性和荧光特性的CdTe@Fe_3O_4/P(NIPAM-co-AA)多功能复合微球是以P(NIPAMco-AA)为模板制备而成.首先,采用溶胀法使模板微球带有磁性;其次,辅助TEOS和APTES两种化学试剂实现对Fe_3O_4/P(NIPAM-co-AA)微球表面的氨基功能化;最后,携带氨基的磁性微球与巯基乙酸修饰的CdTe量子点通过酰胺缩合反应,将量子点键合到磁性微球表面上,最终获得单分散的磁性荧光高分子复合微球.分别采用扫描电子显微镜、透射电子显微镜、倒置荧光显微成像系统、荧光分光光度计以及振动样品磁强计等方法对所获复合材料的结构与性能进行了表征.结果表明:复合微球单分散性良好,平均粒径约为30μm,饱和磁化强度可达5.4emu/g,具有良好的超顺磁性和较高的荧光发光效率.该材料将磁性、荧光结合到微米级高分子共聚物上,不仅解决了纳米粒子分离和处理的困难,而且奠定了多功能材料在生物标记、荧光成像等诸多领域潜在的应用基础.  相似文献   

6.
中空Ag纳米球壳的制备及性能表征   总被引:6,自引:0,他引:6       下载免费PDF全文
 以改性聚苯乙烯微球为模板,采用化学镀法在聚苯乙烯微球表面包覆一层银,在四氢呋喃溶液中将聚苯乙烯微球溶解,得到中空Ag纳米球壳。采用扫描电镜、透射电镜和X射线衍射仪对样品进行了表征及分析,并用紫外可见分光光度计研究了粒子的光学性质。实验结果表明:运用此法成功地制备出中空Ag纳米球壳的内径为250 nm,壁厚约为15 nm,并且成功地使纳米粒子的紫外吸收光谱由600 nm红移至900 nm左右,实现了在可见光至近红外光区调节Ag纳米结构的吸收峰。  相似文献   

7.
纳米银粒子复合膜的制备及光学性质测量   总被引:6,自引:0,他引:6  
李贵安  王应宗  苗润才 《光子学报》2000,29(10):956-960
本文介绍了一种制备纳米复合薄膜的简易方法.以银胶为纳米粒子的来源,将银粒子渗入明胶基质中,成功地制备出纳米银粒子明胶复合膜及染料(FS,Rh6G)包覆纳米银粒子的复合膜.并报道了所制备的复合膜的电镜(TEM)、吸收谱和荧光光谱测量结果.  相似文献   

8.
ZnO纳米球的溶剂热合成及其结构和光学性质   总被引:3,自引:3,他引:0       下载免费PDF全文
针对目前采用溶剂热方法制备的ZnO纳米球尺寸比较大,而模板法制备技术又比较复杂的缺点,用六甲基次胺(HDA)作为辅助试剂,采用溶剂热法制备出了小尺寸的ZnO纳米球。本方法不采任何模板,制备过程简单易操作,重复性好。在场发射电子显微镜下可清楚地看到所制得纳米球尺寸分布比较均匀,每一个纳米球都是由许多粒径在20~30nm的小球共同组成的。X射线衍射结果表明所得产物均为六角纤锌矿结构的ZnO。用谢乐公式算得的粒子尺寸在5~11nm,而且随着制备时间的延长和制备温度的升高,ZnO激子吸收峰发生红移,显示出明显的量子限制效应,这表明那些小球可能是由尺寸更小的ZnO纳米粒子所组成。光致发光谱中紫外发射与可见发射的强度比随着制备时间的延长和制备温度的升高而大,表明ZnO纳米粒子的尺寸增大,结晶性变好。  相似文献   

9.
有机盐制备的Fe3O4-葡聚糖纳米粒子的磁性能及表征   总被引:1,自引:0,他引:1  
利用葡糖酸铁(C12H22FeO14·2H2O)和柠檬酸铁(C6H5O7Fe·5H2O)参与的化学共沉积法制备出单分散核心氧化铁的平均粒径为4.1nm,葡聚糖厚度约为11nm,总体平均粒径为26nm的Fe3O4葡聚糖复合纳米粒子.研究结果表明,复合粒子Fe3O4葡聚糖具有超顺磁性.制备过程中没有N2保护,得到的Fe3O4无机粒子的晶体结构几乎没有发生变化,证明了有机盐的抗氧化性,合成的Fe3O4葡聚糖复合纳米粒子具有较好的磁性能.其在室温下(300K)的饱和磁化强度为52emu/g,低温下(5K)的饱和磁化强度为63emu/g.并利用TEM、XRD、DLS和VSM(振动样品磁强计)等手段对其粒结构、形态、粒径和磁性能进行了表征.  相似文献   

10.
纳滤膜在海水淡化及饮用水净化领域起着越来越重要的作用,核孔膜作为一种重要的分离材料,具有均匀的孔径、可调的孔密度及无缺陷的表面,在水处理及精确分离应用方面有着潜在的优势,高孔密度的超薄核孔膜在制备高性能纳滤膜上具有很大的潜力。基于此,利用氧化锆作选择层,核孔膜作为支撑层制备出了三层结构的有机无机复合纳滤膜,聚多巴胺(PDA)与聚乙烯亚胺(PEI)中间层促进无机纳米粒子在膜表面形成无机层。制备出的复合膜可实现对不同盐的部分截留,表现出的截留顺序为Na2SO4>MgSO4>MgCl2>NaCl。  相似文献   

11.
An electrical-conducting polypropylene/polypyrrole (PP/PPy) composite was prepared by the chemically oxidative modification reaction of pyrrole on the surface of PP particles in suspension. Another type of PP/PPy composite was prepared by mixing the coated PP particles with noncoated PP particles at room temperature. The composites were processed by compression molding or by injection molding. The injection-molded composites exhibited better mechanical properties compared to compression-molded samples, while these composites showed better antistatic behavior and electrical conductivity. The differences in the behavior of the two types of composites were caused by the different structure of the PPy phase, which was studied by hot-stage optical microscopy and X-ray photoelectron spectroscopy (XPS).  相似文献   

12.
旋涂法快速制备双层二元胶体微球有序薄膜   总被引:2,自引:0,他引:2       下载免费PDF全文
刘忍肖  董鹏  陈胜利 《物理学报》2009,58(4):2820-2828
以较大粒径的聚苯乙烯或SiO2胶体微球的单层有序薄膜作基膜,较小粒径的SiO2微球作第二层,用分步旋涂法快速制备了二元双层胶体微球复合有序薄膜.膜中小粒径微球与大粒径微球的粒径比γ=020—056,大粒径与小粒径微球的排列方式可表示为LSxx=1,2,…,13).旋涂速度、旋涂时间、微球悬浮介质的黏度、悬浮液中微球的数密度、旋涂衬底的可润湿性等因素均会影响旋涂组装胶粒薄膜的质量.在旋涂衬底能够被胶体微球悬浮介质完全润湿的前提下,适宜的胶体微球数密度、旋涂速度、旋涂时间是旋涂组装有序薄膜的必要条件. 关键词: 复合有序薄膜 分步旋涂 胶体微球模板  相似文献   

13.
In this study, carbon black/polystyrene electrically conductive composites were obtained by suspension polymerization technique. The composite was characterized using transmission electron microscopy, which indicated two outstanding features concerning to the carbon black; first, that the carbon particles were adsorbed onto the surface of the polystyrene particles, similarly as in the Pickering emulsion phenomenon and second, that the primary aggregate structure of the carbon black was significantly affected by the dispersion process. On the other hand, the composite resistivity was in the order of 200 Ωcm, which was attributed to the direct contact of primary carbon black particles (percolation) and not to the tunneling effect. The obtained composite was evaluated as the electrically conductive element in SBR matrix.  相似文献   

14.
Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.  相似文献   

15.
采用分散聚合反应制备了纳米SiO2/PS包覆粒子,并对其结构进行了表征。首先在超声波场中用表面活性剂对纳米SiO2粒子进行亲油化处理,然后在氮气保护下利用超声波的分散、粉碎、活化、引发等多重作用,在实现纳米SiO2粒子在反应介质中纳米分散的同时,引发苯乙烯单体在纳米SiO2粒子表面发生分散聚合反应,制备出纳米SiO2/PS包覆粒子。最后,采用SEM,TEM,FTIR,XPS等测试手段对纳米SiO2/PS包覆粒子进行了表征,测试结果表明,PS实现了对纳米SiO2的包覆,形成了核壳包覆结构。  相似文献   

16.
In this paper, silver coating on the surface of cenosphere particles was prepared by electroless plating method. The adhesion, oxidation resistance and corrosion resistance properties of silver coating mixed in silicone rubber were investigated. The corrosion characteristic of silver coating was evaluated by anodic polarization curves of the silicone rubber composite in sulfuric acid solution. The results showed that the silver coating on the surface of cenosphere particles was smooth and uniform. The silver film was not oxidized and peeling off during preparation of composite silicone rubber. The adhesion between the cenosphere particle and silver film was good enough. The anodic polarization curves of the silicone rubber composite showed typical activation and passivation transformation. The values of corrosion potential, the initiating passive potential and maintaining passivity potential of composites filled with different contents of Ag-coated cenosphere particles were the same and related to the nature of silver coating. The passive current density of composite increased with increase of the amount of Ag-coated cenosphere particles and was inversely proportional to the resistance of silicone rubber composite. The better the conductivity of silicone rubber composite is, the higher corrosion rate will be.  相似文献   

17.
Based on the 3-(trimethoxysilyl) propylmethacrylate (MPS) modified TiO2 particles, the TiO2/poly (methyl methacrylate) (PMMA) composite particles have been prepared successfully via emulsifier-free emulsion polymerization in water. A facile floating-sinking method is proposed to roughly evaluate the composite particles’ density. Chemical component of obtained composite particles was identified by Fourier transform infrared spectra (FTIR). The morphology and grain size of the composite particles were investigated by field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Thermal analysis of the composite particles was measured by differential thermal analysis-thermo gravimetric analysis (DTA-TGA). The zeta potential and electrophoretic mobility of composite particles with suitable density in water was measured by dynamic light scattering (DLS).  相似文献   

18.
《Solid State Ionics》2006,177(33-34):2967-2977
The LSM/ScSZ composite powder materials for SOFC cathodes were prepared by the mechanical method using an attrition-type particle composing machine and their electrochemical performance was examined. They are designed in such a way that relatively large LSM particles are coated with fine-grained ScSZ particles prior to the electrode fabrication process such as sintering, thus ensuring the establishment of both the ionic and electronic conducting paths within the electrode. The composite cathode using these composite powders outperformed, in the interfacial area specific resistance, a simple LSM cathode and the LSM/ScSZ composite cathode fabricated by an ordinary starting powder mixture without mechanical treatment. The interfacial area specific resistance was actually reduced by 75% relative to the simple LSM cathode, and by 50% relative to the ordinary composite cathode. In addition, the amount of ScSZ doping was reduced down to 20% by weight fraction. The present result suggests that the proposed composite particles can be considered as a potential cathode material in order to enhance SOFC cathode performance.  相似文献   

19.
SnO2-TiO2复合颗粒的形态结构及其光催化活性   总被引:13,自引:0,他引:13  
在气溶胶反应器中,利用TiCl4高温氧化反应制备超细TiO2,采用均匀沉淀法在TiO2表面沉积SnO2制备SnO2-TiO2复合颗粒,应用TEM、EEDS、SRD、BET比表面积测试等手段对粒子进行表征。以活性艳红X-3B复合颗粒,应用TEM、EDS、XRD、BET比表面积测试等手段对粒子进行表征。以活性艳红X-3B溶液为处理对象考察复合颗粒的光催化活性。结果表明SnO2-TiO2复合颗粒的光催化  相似文献   

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