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1.
曹维孝  丛海林 《精细化工》2002,19(9):518-520
从苯乙烯、丙烯酸丁酯和丙烯酸制备了表面带-COOH的不同粒径的乳胶颗粒(-100-400nm)。研究了因水分挥发由毛细管力引起的乳胶颗粒的聚集,以及这些乳胶颗粒和含-N2^ 的高分子(重氮树脂,Mn-2500g/mol)的自组装,结合紫外光照,制备了高分子与乳胶粒交替的三明治(sandwich)结构的超薄膜,结果表明,层与层间的光反应是高分子与乳胶粒成功组装的关键。由于光照中,层与层间的离子键已转变为共价键,这种超薄膜对极性溶剂和盐水溶液非常稳定,在DMF、c(NaCl)=0.1mol/L的水溶液中,室温下(-20℃)分别浸泡24h,组装膜仍完好无损。  相似文献   

2.
铂纳米颗粒自组装膜的微图像化   总被引:1,自引:0,他引:1  
从硝基重氮树脂(NDR)与包裹巯基乙酸的铂纳米颗粒(MA-PtNP)的静电自组装,制备了感光性的自组装多层超薄膜,经选择性紫外曝光和十二烷基硫酸钠(SDS)水溶液显影,光照部分的膜,因层与层之间的离子键转变为共价键,不再被SDS水溶液洗脱而留下来;未光照部分的膜,层与层之间仍是离子键,在显影时被除去,从而形成图像、用AFM和SEM对形成的图像进行了表征.  相似文献   

3.
超细羟基磷灰石颗粒的反相微乳液合成   总被引:17,自引:0,他引:17  
采用AOT/异辛烷/Ca(H2PO4)2*H2O水溶液体系的微乳液与AOT/异辛烷/Ca(OH)2饱和溶液体系的微乳液反应,制备出了平均颗粒尺寸107nm,呈单分散的球形HAP超细颗粒.通过制备过程优化和AOT/异辛烷/Ca(H2PO4)2*H2O水溶液三元相图,确定了基本制备条件为AOT浓度0.1mol/dm3,正辛醇浓度0.1mol/dm3,增溶水量为w=9.采用该体系可改变HAP超细颗粒的生长习性,从而实现对HAP颗粒形貌的控制.  相似文献   

4.
选用大小粒径分别为200nm和21nm的TiO2颗粒,采用刮涂法制备了几种不同条件的TiO2薄膜电极,研究了大小颗粒TiO2的复合方式和质量比对其所组装染料敏化太阳能电池光电性能的影响。应用红外吸收光谱仪和扫描电子显微镜对TiO2薄膜电极进行了表征,在100mW/cm2(AM 1.5G)光照下,测试了电池的光电性能。结果表明:将大颗粒TiO2作为光散射层,且大颗粒TiO2和小颗粒TiO2质量比为1∶3时,所制薄膜不但可以保持纳米粉体高比表面积的优点,同时可以提高对太阳光的散射率,用其组装的电池光电性能最好,转换效率达到2.46%。  相似文献   

5.
TiO_2薄膜光催化氧化I~-的研究   总被引:1,自引:0,他引:1  
采用溶胶 凝胶法 ,在玻璃珠表面涂覆均匀透明的TiO2 薄膜并制成光催化反应器 ,对水溶液中I- 的光催化氧化进行了研究 .比较了光催化剂的活性 ,讨论了I- 的起始浓度、试液的酸度、光照时间与I2 产率的关系 .实验结果表明 :采用锐钛型TiO2 作光催化剂 ( 3L碘化钾溶液所用催化剂量为 4 0 g) ,当 [I- ]=0 .3mol/L ,[H+ ] =3.0mol/L ,光照 8h时 ,I2 的产率达到 4 1 2 6% .  相似文献   

6.
采用全纳米颗粒自组装的方法,在棉、锦纶和涤纶织物上制备了TiO_2/SiO_2薄膜,再经十六烷基三甲基硅烷修饰,得到了兼具抗紫外及超疏水功能的多种织物。自组装过程中分别以SiO_2和Ti_2溶胶为原料,逐层于聚电解质表面处理的织物上组装了TiO_2/SiO_2多层薄膜。经扫描电子显微镜(SEM)测试表明,膜层均匀沉积在织物纤维表面。接触角测试表明,疏水处理后表面水的接触角可达172°。紫外可见分光光度计测试表明,经TiO_2/SiO_2修饰后,织物在紫外光区的吸光度成倍提高。用耐老化、耐摩擦、耐水流喷射等耐久性试验评价了织物在使用过程中可能遇到的各种破坏,证明自组装再经疏水剂处理的织物具有良好的耐久性。  相似文献   

7.
孙萌萌  浦敏锋  曹灿  刘梅堂 《广州化工》2010,38(12):100-101,122
以精制钠基蒙脱石(Na-MMT)、有机化蒙脱石(OMMT)和聚乙烯醇(PVA)为原料,通过水溶液插层-流延成膜法制备纳米复合薄膜。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和热重分析(TGA)对复合材料的结构和性能进行表征,重点探讨蒙脱石有机化对PVA/MMT复合薄膜性能的影响。结果表明Na-MMT和OMMT纳米颗粒在PVA基体中均得到了良好分散;有机改性剂的存在促使PVA/MMT复合薄膜的MMT片层间距扩撑更大,但由于其与PVA相容性较差,导致有效插入MMT片层间的PVA分子较少,PVA/MMT复合薄膜的热稳定性改善效果不明显。  相似文献   

8.
与均相催化剂相比,负载型催化剂能够有效控制产物形态和聚合活性。以2,7-叔丁基芴基胺基二甲基钛[t-BuNSiMe_2(2,7-di-t-BuFlu)TiMe_2]为催化剂、改性甲基铝氧烷/二氧化硅(MMAO/SiO_2)为负载、乙烯和10-十一烯-1-醇为单体,制备了一系列超高分子质量乙烯/十一烯醇共聚物。研究结果表明:控制聚合活性在1000~2000 kg/(mol·h)时,可得到形态均一、稳定的超高分子质量聚乙烯共聚物颗粒,共单体插入率最高达5.3%;同时,共聚物有着不错的结晶度。  相似文献   

9.
采用硼氢化钠还原金盐溶液,制备了晶粒尺寸为5 nm的金溶胶,以静电吸附的方法将Au纳米晶均匀地沉积在FTO玻璃基全纳米颗粒组装的SnO2/TiO2薄膜内,用SEM、EDS、TEM、光电流密度等方法对金修饰的全纳米颗粒组装SnO2/TiO2薄膜(Au-SnO2/TiO2)进行了表征.金纳米晶修饰后,光电流密度较相同厚度的SnO2/TiO2薄膜提高了128.3%,更加有利于光生电子的迁移.将Au-SnO2/TiO2薄膜用作染料敏化太阳能电池(Dye-sensitized solarcells,DSSCs)的阻挡层后,发现复合薄膜有效地阻止了导电玻璃基底上光生电子与电解液中I3-的复合,提高了DSSCs的光电转换效率.不同厚度的Au-SnO2/TiO2阻挡层复合薄膜中,含6层Au-SnO2/TiO2复合薄膜阻挡层的DSSCs最终效率为7.12%,较常用的TiCl4稀溶液预处理FTO玻璃的工艺(6.06%)提高了17.5%.  相似文献   

10.
采用低温液相薄膜制备工艺--连续离子层吸附反应(SILAR)法,在玻璃衬底上制备了纳米Cu2O薄膜,考察了工艺参数对薄膜质量和薄膜表面形貌的影响,对薄膜的生长速率与反应溶液浓度、反应温度以及循环次数的关系进行了研究和分析。结果表明,采用连续离子层吸附反应(SILAR)法有利于制备高质量的纳米Cu2O薄膜,连续离子层吸附反应(SILAR)法可以有效去掉疏松的离子,每次循环吸附反应都能使紧密吸附的离子转化成致密的纳米Cu2O薄膜,这样既有利于纳米Cu2O颗粒的生成,同时减少了污染和降低了成本。试验表明,制备纳米Cu2O薄膜的最佳反应温度为70℃,最佳反应溶液浓度均为1 mol/L,纳米Cu2O薄膜的膜厚随着循环次数的增加而增加,循环40次可制得厚度为0.38μm的薄膜。经XRD和SEM测试,所制备的薄膜纯度高,表面平整且致密,Cu2O颗粒大小约为100 nm。  相似文献   

11.
丙烯酸改性聚氨酯的合成与性能的研究   总被引:4,自引:0,他引:4  
采用聚丙烯酸酯与聚氨酯共混、以水性聚氯酯为种子乳液进行丙烯酸种子乳液聚合以及水性聚氨酯与丙烯酸接枝共聚3种方法分别得到丙烯酸改性水性聚氯酯,通过激光散射粒径仪测定乳胶粒的粒径、乳胶膜的透明性、傅里叶变换红外光谱(FTIR)结构分析以及扫描电镜(SEM)对乳胶膜结构和表面形貌进行分析。结果表明:采用种子乳液聚合反应和接枝反应所得到的丙烯酸改性水性聚氯酯乳液乳胶粒粒径比水性聚氨酯的粒径显增大,表现出良好的相容性;由种子乳液聚合和接枝聚合制备的丙烯酸改性水性聚氯酯胶膜中颗粒与颗粒之间结合紧密,表面光亮、透明。  相似文献   

12.
BACKGROUND: To create a hydrophobic surface, a commonly used two‐step process is the formation of a rough surface and its subsequent modification with materials of low surface energy. Here, a new method for making a hydrophobic surface is proposed using emulsion copolymerization with a low‐surface‐energy fluoropolymer in the presence of a high percentage of silica particles creating a well‐spread roughness. RESULTS: Irregular core–shell structural composite particles such as of snowman shape and sandwich shape were obtained and characterized. The hydrophobicity and chemical structure of the hybrid film were investigated. It was found that strong inter‐ and intramolecular chemical bonding in the composite film may improve the properties of the hybrid film. Enrichment of fluorine on the film surface and well‐distributed roughness due to the silica particles covered by the fluoropolymer contribute to the increased hydrophobicity of the film. The water contact angle on the film increased from 106 ± 2° to 135 ± 2°. CONCLUSION: The stable core–shell hybrid latex synthesized in this work will be of use in preparing high‐performance hydrophobic aqueous coatings. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
PDMS乳液/硅溶胶杂化水分散体系及其复合膜的制备与表征   总被引:1,自引:1,他引:0  
以聚硅氧烷(PDMS)乳液/硅溶胶杂化水分散液为成膜基质,硅烷偶联剂KH 550为固化剂,制备了双组分水基有机硅涂料;将其固化后得到PDMS/硅溶胶复合膜。通过水分散液的粒径分布及红外光谱分析,研究了水分散液的脱水成膜过程;采用扫描电镜(SEM)和原子力显微镜(AFM)对复合膜的断面和表面形态进行了表征。结果表明:PDMS乳液加入硅溶胶后,粒径分布变宽,粒径略有增加;成膜后,硅溶胶粒子与PDMS长链发生了相互作用,并作为分散相被包埋在PDMS中;复合膜表面形成簇状结构,表面粗糙度随着硅溶胶含量的增加而增加。当硅溶胶与PDMS乳液的固体质量比由10%增加到30%时,复合膜的拉伸强度由0.76MPa升高到3.10MPa,而拉断伸长率从680%下降到470%。  相似文献   

14.
Anionic aqueous polyurethane dispersion was synthesized through self‐emulsifing method from cycloaliphatic isophorone diisocyanate (IPDI) and dimethylolpropionic acid (DMPA). The carboxyl acid group in DMPA was used to make the polyurethane dispersible. The polyurethane/polyacrylate (PU/PA) composite particles were also prepared by seeded surfactant‐free emulsion polymerization; the cycloaliphatic polyurethane aqueous dispersion was used as seed particles. The structures and properties of the composite emulsion as well as the physical mixture of polyurethane dispersion and polyacrylate emulsion were characterized by FTIR, DSC, dynamic light scattering, TEM, X‐ray photoelectron spectroscopy (ESCA), and electronic tensile machine. The results showed that the synthesized PU/PA composite emulsion was found to form inverted core‐shell structure with polyacrylate as the core and with polyurethane as the shell, and its diameter of particles is in the range of nanograde, the crosslinking reaction was existed in composite emulsion. The intimate molecular mixing of crosslinking polymers are also claims to result in a superior balance of properties compared to physical blends of polyurethane dispersion and acrylate emulsion. The crosslinking mechanism of PU/PA composite emulsion was also discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

15.
纳米TiO_2/硅丙复合乳液的光催化抗菌性能研究   总被引:4,自引:1,他引:4  
采用原位聚合法制备纳米TiO2 /硅丙复合乳液。由透射电子显微镜观察到纳米TiO2 /硅丙复合乳液胶膜中纳米颗粒呈单分散状态,达到了纳米尺寸。通过分光光度分析方法,测得该膜在 200 ~400nm紫外光光波范围吸收强度大于 2 0,在可见光光波范围有明显的光吸收。杀菌实验测试结果为:该乳液对枯草杆菌黑色变种芽孢、大肠杆菌和金黄色葡萄球菌的杀灭率达到 98%以上;该乳液胶膜对乙肝表面抗原 (HbsAg)作用 8h以后,HbsAg由阳性转变为阴性。研究表明,纳米TiO2 /硅丙复合乳液及其乳液胶膜具有显著的光催化效应,能将其吸收的光能转化为杀菌、抗病毒的化学能。  相似文献   

16.
乙烯基三乙氧基硅烷/丙烯酸酯共聚乳液的研究   总被引:4,自引:2,他引:4  
以聚丙烯酸丁酯为种子乳液,将乙烯基三乙氧基硅烷(VTES)与丙烯酸酯进行乳液共聚,制成了聚合稳定性良好,性能稳定的有机硅/丙烯酸酯共聚乳液,详细讨论了VTES用量对聚合过程稳定性和乳液粒径大小及分布的影响,采用动态光散射法跟踪了聚合过程的粒径大小及分布,采用TEM表征了粒子形态;同时研究了乳液的粘度及乳胶膜的耐水性能,结果表明:乳胶粒的平均粒径随聚合时间的延长逐渐增大,乳胶粒呈球形,具有核壳结构,随着VTES用量的增加,乳液聚合的稳定性变差,乳胶粒的平均粒均增大,乳液的粘度增加,乳胶膜的吸水率减小。  相似文献   

17.
研究了采用反相微乳液法制备TiO2/ ZrO2复合微乳液,并以其作为前体制得TiO2/ ZrO2复合膜。通过对复合微乳液的透射电镜测试,结果表明TiO2/ ZrO2复合微粒在油相包裹的“水池”中生成。由扫描电子显微镜观察到TiO2/ ZrO2复合膜表面微粒以棒状形式分布,而且复合膜对大肠杆菌的灭菌率达98 %~99 %。  相似文献   

18.
In this study, ultrasonic irradiation and in situ emulsion polymerization were combined to prepare stable poly(methyl methacrylate‐con‐butyl acrylate) (P(MMA‐BA))/carbon nanotubes (CNTs) composite emulsion, which solves the dispersion problem of CNTs in the latex. Two stages were adopted. In Stage I, ultrasonically initiated in situ emulsion polymerization was conducted to disperse CNTs and prepare the seed emulsion containing polymer coated CNTs. In Stage II, conventional in situ emulsion polymerization was conducted to further enhance the monomer conversion and solid content. The dispersion behavior of MWCNTs in aqueous solution under ultrasonic irradiation was investigated by spectrophotometry. The effects of CNTs content on the emulsion stability and mechanical properties of composite film were studied. The results suggest that in the composite emulsion the long CNTs with a diameter of 20–40 nm are separated and dispersed by the formed polymer latex nanoparticles with a size of 20–40 nm. The spherical polymer latex nanoparticles adhere to the wall of CNTs to form a structure like “grapes on the twig.” The smooth, uniform, and flexible polymer/CNTs composite films were prepared from the composite emulsion. The CNTs can be individually dispersed in P(MMA‐BA)/CNTs composite film. Tensile tests suggest that with the increase in the CNTs content, the Young's modulus and the yield strength of the film increase. Only at 1 wt % CNTs, the Young's modulus increases from 124 to 289 MPa, and the yield strength is improved about ~14%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3123–3130, 2006  相似文献   

19.
《分离科学与技术》2012,47(4):937-953
Abstract

The Mg-silicate microballoons containing CYANEX923 were prepared by W/O/W emulsion. The diameter of obtained micro-sphere particles was ~10 µm and shell thickness was 2 µm. The adsorption of Co(II) and Ni(II) from aqueous solutions using prepared micro-sphere particles was investigated. Experiments were carried out as a function of solute concentration and temperature (25–60°C). Several kinetic models were used to test the experimental rate data and to examine the controlling mechanism of the adsorption process. Equilibrium adsorption data were analyzed using Langmuir isotherm model. The results indicated that prepared micro-sphere particles can be used as an efficient adsorbent for the removal of Ni(II) and Co(II) from aqueous solution.  相似文献   

20.
张倩 《精细化工》2021,38(1):192-199,211
根据色粉纸表面固砂的性能要求,以丙烯酸丁酯(BA)、甲基丙烯酸异辛酯(EHMA)为软单体、丙烯酸甲酯(MA)、甲基丙烯酸甲酯(MMA)为硬单体,丙烯酸羟丙酯(HPA)为交联单体,甲基丙烯酸(MAA)、甲基丙烯酸缩水甘油酯(GMA)作为功能单体,采用半连续种子乳液聚合法,制备了具有核壳结构的水性丙烯酸酯树脂乳液(WSAE-G),进一步将其作为色粉纸表面固砂用黏合剂和成膜剂.讨论了GMA用量对乳液粒径、稳定性和黏度等的影响.利用DLS和TEM对乳液乳胶粒子的大小及形貌进行了表征,使用TG、DSC以及万能材料试验机对胶膜的性能进行了测试.对固砂产品表面进行SEM测试.结果表明:GMA用量为1%(以混合单体总质量为基准,下同)时,乳液粒径为142.4 nm,PDI为0.063,乳液分散稳定指数(TSI)为0.162287.TEM显示,乳液具有清晰的核壳结构.胶膜拉伸强度达9.057 MPa.制得的色粉纸层间结合力为244.9 J/m2,所形成的固砂层均匀、磨砂性较好且不易掉砂.  相似文献   

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