SOL-GEL法制有机聚合物/无机纳米粒子复合材料

归纳了SOL－GEL法制有机／无机纳米复合材料（ONIC）的复合方法,如：有机聚合物存在下形成无机相纳米粒子;无机纳米相存在下进行有机单体聚合;无机溶胶与有机聚合物溶液共混,再凝胶化,用杂交法将有机单体与无机溶胶同步聚合形成互贯网络,这种复合材料的最大结构特点是微区的大小在纳米尺寸范围内,也可是互相贯穿的,其材质是高度透明的,耐热,热分解温度和力学强度比纯聚合物有较大的提高。     

Preparation of long alumina fibers by sol-gel method using tartaric acid

Long alumina fibers were prepared by sol-gel method.The spinning sol was obtained by mixing aluminum nitrate,tartaric acid,and polyvinylpyrrolidone with a mass ratio of 10∶3∶1.5.Thermogravimetry-differential scanning calorimetry (TG-DSC),Fourier transform infrared (FT-IR) spectra,X-ray diffraction (XRD),and scanning electron microscopy (SEM) were used to characterize the properties of the gel and ceramic fibers.A little of α-Al2O3 phase is observed in the alumina precursor gel fibers sintered at 1273 K.The ...     

Synthesis and Microstructure of Doped Alumina Composite Membrane by Sol-Gel Process

1　IntroductionMembranecanbedefinedasasemi permeablebarri erthatpreventsfromintimatecontactbetweentwohomo geneousphases,butallowspreferentialpassageofcertainspeciesacrosstheirsurface .Asamaterialbase,theinor ganicceramicmembranehasexcellentpotentialapplica tionsandadvantages,buttheporesofceramicmembranevarywithacertaincondition,whichhasgreateffectsonthehighselectivity,chemicalandmechanicalstability,andcatalyticproperties.Manyresearcheshavebeencon ductedbyseverallaboratoriestogetabetterporedis …     

Preparation of Hydroxyapatite/Polylactide Biocomposites by Absorption Process in Liquid Phase

The hydroxyapatite/polylactide biocomposites were prepared by absorption process in liquid phase. The method avoided many disadvantages, such as inaterfusion of chemical impurity substances, nonuniformity dispersal of HA in PLA, low molecular weight of PLA . HA particles were uniformly dispersed in PLA matrix, and showed well ndhesion with PLA matrix. The biocomposites have the higher mechanical properties and suitable decomposable capability.     

Preparation of Hydroxyapatite/Polylactide Bicomposites by Absorption Process in Liquid Phase

1Introduction ThePLA HAbiocompositeshavegoodbiocompati bilityandfinemechanicalproperty,andtheydonotneed secondoperationandwouldnotreleasemetalionwhich canbringaseriesofuntowardeffects.Thehydroxyapa tite polylactidebiocompositesaregreatlyusedinmanyas pects…     

A comparative study of drying techniques on the morphology of porous silica gels synthesized via sol-gel process

The effect of drying techniques on the microstructure,morphology and pore structure of porous silica gels was studied in the paper.The gels were prepared by using sol-gel process and different drying routes:freeze-drying (FD),low pressure drying (LPD),high temperature drying (HTD) and chemical modification & ambient drying (CMD) techniques.Observation under pore distribution and structural properties showed that CMD technique leads to homogenous mesoporous silica material with specific surface area of 745 m2/g,and the average pore size around 20 nm,while LPD and HTD result in loosely packed particles with non-isotropic aggregation pattern.The specific surface areas of LPD and HTD samples are 419 and 513 m2/g respectively,and the pore size distribution of the samples are observed distributing widely in range of 10-100 nm.Freeze drying method is a new but prospective way to prepare mesoporous silica.The specific area of FD sample is around 500 m2/g.By the comparison for the properties of the gels,this paper wants to induce a further interest in finding a proper method to synthesize the porous silica gels for low price use.     

一步法制备羟基磷灰石/丝素蛋白复合材料的条件研究

提出了一种制备HA/SF复合粉末的新方法.以磷酸氢二钠、无水氯化钙和丝素蛋白为原料制备羟基磷灰石/丝素蛋白(HA/SF)复合粉末,通过X-射线衍射(XRD)、扫描电子显微镜(SEM)和红外吸收光谱(FIR)等检测手段,探讨了反应酸度、反应温度、反应时间,丝素蛋白加入量和原料加入顺序对制备HA/SF复合粉末的影响,确定了最佳的制备条件;该方法可降低溶解丝素蛋白的温度,达到节约能源的目的.     

溶胶凝胶法制备氧化亚铜薄膜及其工艺条件

以单质锂、无水甲醇和氯化铜为原料,葡萄糖为还原剂,醋酸为络合剂,采用溶胶 凝胶法在玻璃基片上制备Cu2O薄膜,并确定了制备的工艺条件:CH3OH及CuCl2·2H2O为原材料,C6H12O6·H2O为还原剂,CH3COOH为络合剂。通过X射线衍射仪、紫外 可见分光光度计和扫描电镜等分析和表征,确定了影响Cu2O薄膜性质的因素。结果表明:用溶胶 凝胶法可以制备具有良好性能的Cu2O薄膜。     

溶胶凝胶法制备氧化亚铜薄膜及其工艺条件

以单质锂、无水甲醇和氯化铜为原料,葡萄糖为还原剂,醋酸为络合剂,采用溶胶 凝胶法在玻璃基片上制备Cu2O薄膜,并确定了制备的工艺条件:CH3OH及CuCl2·2H2O为原材料,C6H12O6·H2O为还原剂,CH3COOH为络合剂。通过X射线衍射仪、紫外 可见分光光度计和扫描电镜等分析和表征,确定了影响Cu2O薄膜性质的因素。结果表明:用溶胶 凝胶法可以制备具有良好性能的Cu2O薄膜。     

Sol-gel法制备介孔WO3-TiO2复合材料及其光催化性能

以非离子表面活性剂P123为结构导向剂,采用溶胶-凝胶法,通过调整P123与(W+Ti)的摩尔比例,经500℃煅烧制备出一系列不同介孔特性的WO3-TiO2复合光催化材料。利用X射线衍射图谱(XRD)、扫描电子显微镜(SEM)、紫外-可见吸收光谱(UV-Vis)、比表面积分析仪(BET)对复合材料的形貌、孔结构及光谱性质进行表征。研究了介孔WO3-TiO2复合材料对罗丹明B的吸附/光催化降解能力。结果表明,以P123为模板剂所制备的介孔WO3-TiO2复合材料表现出较好的吸附/光催化性能,可见光照射下,0.5g的P123、(W+Ti)摩尔比为0.6%的复合材料经500℃煅烧,对200mL罗丹明B(10mmol/L)的吸附降解率140min后达到97.7%。     

溶胶—凝胶法合成的羟基磷灰石的热稳定性研究

用溶胶－凝胶法法合成了具有不同Ca/P摩尔比的羟基磷灰石（HAP）和不同CO3^2-含量的碳羟磷灰石（CHAP），采用DTA，TG，XRD，FT－IR，BET比表面积测定，晶粒密度测定等方法研究了此两类磷灰石的热稳定性，探讨了影响热稳定性的晶体结构因素，结果表明；（1）由于Ca亏HAP存在空位缺陷结构，在781℃脱羟分解，正常配比HAP不存在缺陷结构，Ca盈HAP由于存在的是填隙缺陷结构，表现出较高的热稳定性，甚至于在1100℃仍不脱羟分解；（2）在150－180℃范围内脱除CHAP中的CO3^2-是非平衡态的连续固溶体分解，同时其结晶度增加且晶粒重结晶长大，CO3^2－质量分数含量小于3．34的CHAP在776℃时脱羟分解，CO32-质量分数≥3．34％的CHAP在150－1100℃范围内不发生脱羟分解。     

Dielectric Behavior of Nano-PbTiO3/PVDF Nanocomposites In-situ Synthesized by the Sol-gel Method

PbTiO3 / PVDF nanocomposites were prepared via in-situ growth of nanosized PbTiO3 particles in PVDF matrix by sol-gel method. Nanosized PbTiO3 grown in the composites film was characterized by X-ray diffractometry （XRD） and transmission electron mieroscopy, and the dielectric properties of the composite films prepared were measured. The distribution of PbTiO3 nanoparticles in-situ grown in the PVDF matrix was examined using a scanning electron microscope. The relative dielectric eonstant increases with increasing the weight fracture of PbTiO3 in-situ grown. In particular, the dielectric loss monotonically decreases with the increase of PbTiO3 content at 1 MHz.     

镧钴氧化物合成的溶胶凝胶形成过程分析

着重研究了柠檬酸对溶胶凝胶法合成LaxCo2-xO3-δ的凝胶形成过程的影响,通过分析溶液颜色变化与钴配位环境的关系,阐明溶液体系pH值、陈化时间对凝胶形成的影响作用。根据凝胶的红外谱图分析了凝胶中金属离子与柠檬酸的配位方式,以及论证了凝胶体系是由金属离子与柠檬酸相互连接而形成的网络结构。     

Electrochemical performance of LiFePO4/（C＋Fe2P） composite cathode material synthesized by sol-gel method

A LiFePO4/(C+Fe2P) composite cathode material was prepared by a sol-gel method using Fe(NO3)3·9H2O,LiAc·H2O,NH4H2PO4 and citric acid as raw materials,and the physical properties and electrochemical performance of the composite cathode material were investigated by X-ray diffractometry(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and electrochemical tests.The Fe2P content,morphology and electrochemical performance of LiFePO4/(C+Fe2P) composite depend on the calcination tempera...     

Fabrication and characterization of highly ordered Ni0.5Zn0.5Fe2O4 nanowire/tube arrays by sol-gel template method

Highly ordered nanowire/tube arrays of Ni0.5Zn0.5Fe2O4 were fabricated by the sol-gel method in the pores of anodic alu- mina membrane (AAM). Whether nanowires or nanotubes were fabricated depends on immersion time. The immersion time was 15-40 s for nanotubes and over 60 s for nanowires. The topography and crystalline structure of the nanowire arrays were character- ized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). It was found that the length and diameter of the Ni0.5Zn0.5Fe2O4 nanowires are related to the thickness of the AAM and the diameter of the pores. The results indicated that the Ni0.5Zn0.5Fe2O4 nanowires are uniform and parallel to each other.     

Preparation and Characterization of Pb（Zr0.52Ti0.48）03 Ultrafine Powders by a Sol-gel Combined with Combustion Process

A simple and rapid process for synthesizing lead zirconate titanate,Pb（Zr0.52Ti0.48）O3（PZT）,ferroclectric powders was developed.This process,combining the sol-gel and combustion process.offers several advantages over conventional methods.including rapid solution synthesis,use of commercially available materials lower synthesis temperature and ease of obtaining ultrafine powders.The precursor solution for synthesizing powders was prepared from lead nitrate.zireonium nitrate.titanium oxynitrate,citric acid and deionized water.The precarsor was investigated by DSC-TG,and the PZT powders were investigated by powder-XRD,IR spectra and TEM.XRD analysis shous that the powders possess a single phase perovskite type structure,no pyrochlore phase exists.and TEM image shows that the grain size of the powders is about 40nm.     

医用SiO_2气凝胶/壳聚糖复合材料的制备

用环境干燥法,通过静电作用制备了SiO2气凝胶/壳聚糖复合材料。SiO2气凝胶为基体,乙醇水溶液为分散介质,三聚磷酸钠为强电解质。采用扫描电镜、红外光谱仪分析其形貌和组成,并实验研究了此复合材料对药物庆大霉素(Gen)的担载能力。结果表明,这种SiO2气凝胶/壳聚糖复合材料对药物包覆率为17.32%。     

Microstructure and electrical properties of La2O3-doped ZnO-based varistor thin films by sol-gel process简

Microstructure and electrical properties of La2O3-doped ZnO-Bi2O3 thin films prepared by sol-gel process have been investigated. X-ray diffraction shows that most diffraction peaks of ZnO are equal, and the crystals of ZnO grow well. Scanning electron microscopy and atomic force microscopy results indicate that the samples have a good structure and lower surface roughness. The nonlinear V-I characteristics of the films show that La2O3 develops the electrical properties largely and the best doped content is 0.3% lanthanum ion, with the leakage current of 0.25 mA, the threshold field of 150 V/mm and the nonlinear coefficient of 4.0 in detail.     

Preparation of AgSnO2 composite powders by hydrothermal process

Silver-tin oxide powders were synthesized by the hydrothermal method with Ag（NH3）2^＋ solution and Na2SnO3 solution as raw materials and Na2SO3 as reductant. The precipitation conditions of Na2SnO3 solution and the reduction conditions of Ag（NH3）2^＋ were also investigated. The powders prepared were characterized by differential thermal analysis （DTA）, X-ray diffraction analysis （XRD）, scanning electron microscope （SEM） and energy spectrum analysis, The results show that pH value of the solution is a key parameter in the formation of Sn（OH）4 precipitate and the reduction reaction of Ag（NH3）2^＋ can release H^＋ ions, which results in synchronous precipitation of Sn（OH）6^2- as Sn（OH）4. The reduction of Ag（NH3）2^＋ and precipitation of Na2SnO3 occur simultaneously and the coprecipitation of silver and tin oxide is reached by the hydrothermal method. The silver-tin oxide composite powders have mainly flake shape of about 0.3 μm in thickness and there exists homogeneous distribution of tin oxide and silver in the powder synthesized.