Synthesis of C60 Fullerene-Silica Hybrid Nano Structures

We have recently demonstrated a procedure for the synthesis of silica nanometer and micrometer particles under modest conditions. Here we report the synthesis of C₆₀ fullerene-silica hybrid nanometer sized materials via sol-gel processing at neutral pH and under ambient conditions. The C₆₀ fullerene, when functionalized, was water-soluble and also able to facilitate the formation of silica structures from an aqueous silica precursor. This C₆₀ fullerene had similar functionality to the cationically charged polymers, which have been reported earlier to act as catalysts/templates for silicification. The resulting organic-inorganic hybrid was studied using SEM, EDS and UV/Vis spectroscopy. These hybrid materials may have applications in areas such as optical devices, semiconductors, chemical sensors, catalysis and in the medical field. The results presented in this study may be useful in developing a process for the synthesis of novel organic-inorganic nanometer sized materials and for the biomimetic synthesis of silica.     

疏水性聚倍半硅氧烷纳米杂化材料的合成及性能

以甲基三乙氧基硅烷（MTES）和十二烷基三甲氧基硅烷（DTMS）为前驱体,以NaOH为催化剂,在乙醇-水体系中进行水解-缩合反应,制得了一种疏水性聚十二烷基/甲基倍半硅氧烷纳米杂化材料（PDMSQ NPs）。通过FTIR和XPS对PDMSQ NPs的化学结构进行了表征;用DLS、FE-SEM及 TGA等对PDMSQ NPs的平均粒径、微观形貌和耐热稳定性进行了考察,对其合成工艺条件进行了优化。结果表明,PDMSQ NPs表面C元素含量高达41.73 %,电子结合能103.04 eV处归属为聚倍半硅氧烷中Si 2p的特征峰,PDMSQ NPs为表面含十二烷基和甲基且以Si—O键为骨架的纳米球结构。PDMSQ NPs失重5 %时温度为351 ℃,表明PDMSQ NPs热稳定性优良。FE-SEM分析可知,当反应温度为60℃,n(MTES)∶n(DTMS)=10∶1.0~10∶1.4时,制得的PDMSQ NPs表面光滑、呈单分散性规整球形,水静态接触角最高达168°。提出了PDMSQ NPs的形成机理。     

Template-Based Synthesis of Nano/Micro Structures on a Semiconducting Substrate

In recent years, nano/micro wires have attracted considerable attention because of their extraordinary physical properties and enormous potential for applications in numerous fields of research and technology. Among the methods widely used to create nanowires, electrochemical deposition in the pores of ion-track polymer membranes have turned out to be very suitable. This method may also be used to synthesize nano/micro structures on the substrate itself to prevent post-synthesis manipulations. For this, the polycarbonate layer is spin coated on the semiconducting substrate and then irradiated with heavy ions. Chemical etching of these latent tracks leads to the formation of nano-/micro-size pores. After depositing metal in these pores, the polycarbonate templates are removed by dissolving them in dichloromethane, leading to the formation of nanowires standing on the substrate itself. Using this technique, we have studied VI characteristics of metallic nano/micro wires grown on the silicon substrate. These nano/micro structures show Schottky behavior when forward biased and ohmic behavior when reversed biased.     

Synthesis of Trinitrophenyl C60 Derivative

Trinitrophenyl C₆₀ derivative was synthesized by allowing C₆₀ to react with trinitrochlorobenzene and sodium azide. This fullerene derivative would first provide a brillant prospect in the energetic materials. The product structure was identified by FD-MS, UV-VIS, IR and ¹³C-NMR.     

纳米SiO_2杂化氟硅丙烯酸树脂的合成及应用

以过氧化苯甲酰(BPO)为引发剂,将甲基丙烯酸十二氟庚酯(G04)与丙烯酸正丁酯(BA)、丙烯酸羟乙酯(HEA)、乙烯基三乙氧基硅烷(VTES)、苯乙烯(ST)进行溶液聚合,采用逐步滴加法合成了氟硅丙烯酸预聚体(FB-VI),再用正硅酸乙酯对其杂化得到纳米SiO_2杂化氟硅丙烯酸树脂(FB-VINA)。用红外光谱仪对产物FB-VI-NA的化学结构进行了表征;并以FB-VI-NA为基料制备涂层,测试了其疏水性、硬度等性能。结果表明:正硅酸乙酯质量分数为6%,溶液p H=4,固化温度为130℃时,涂层的外观、耐冲击性、附着力、疏水性较好;与传统改性丙酸树脂相比,涂膜的硬度明显提高。     

Structures and field emission properties of heat-treated C60 fullerene nanowhiskers

The structures and field electron emission properties of C₆₀ fullerene nanowhiskers were investigated. The single crystalline C₆₀ fullerene nanowhiskers were straight, surrounded by facets, and had a uniform submicrometer diameter along the long axis. Heat treatment of the nanowhiskers drastically transformed the inner structure from C₆₀ crystal to glassy carbon, while the outer structure kept its original morphology despite heat treatment. Field electron microscopy images of the heat-treated nanowhiskers showed striped patterns, characteristic of an agglomerate of crumpled graphitic layers.     

硫酸体系中快速反应制备聚苯胺纳米结构的研究

聚苯胺纳米结构同时具有导电高分子材料和纳米材料的优点,具有广阔的应用前景.本文在硫酸体系中,通过快速混合氧化反应制备得到了质量较好的聚苯胺纳米纤维.利用扫描电镜(SEM)、红外光谱(FTIR)和紫外可见光谱(UV-Vis)对产物进行了表征,探讨了反应物配比对产物形貌的影响和不同反应条件对产率的影响.结果表明过硫酸铵用量对产物形貌和产率影响最为显著;当苯胺与过硫酸铵配比为0.8时,所得纳米纤维形貌最好,直径约为60～100 nm,长度约为500 nm到几个微米,并且以掺杂态形式存在.同时考虑产物形貌和产率的最佳合成条件为:硫酸浓度1 mol·L-1,苯胺与过硫酸铵配比为0.8,反应时间为16 h.     

紫外光固化纳米复合树脂的制备

采用正交实验设计,以N-乙烯基吡咯烷酮、丙烯酸丁酯为活性单体,环氧丙烯酸酯树脂为预聚物,纳米氮化硅粉体为无机填料制备出性能较好的紫外光固化纳米复合树脂。该纳米复合树脂与基体树脂相比较,体积收缩率降低38%,拉伸强度提高31%。透射电镜测试表明:在纳米复合材料中,纳米S i3N4粉体均匀分散在基体中;红外光谱表征表明,纳米S i3N4和基体树脂之间存在相互作用力。     

Synthesis and photoconducting properties of C60‐bonded polystyrene initiated with C60Cln

C₆₀‐bonded polystyrene was produced with a novel initiator system, C₆₀Cl_n/CuCl/2,2′‐bipyridine (where the average value of n is 20). The molar ratio of styrene/C₆₀Cl_n/CuCl/bpy was 100:1/20:1:2, and the polymerization temperature was 130°C. Gel permeation chromatography detected with an ultraviolet detector demonstrated that C₆₀ was chemically bonded to polystyrene. The linear increase in the number‐average molecular weight (by gel permeation chromatography) with the conversion indicated that this novel initiator system had some characteristics of living polymerization. A possible polymerization mechanism was examined. The photoconducting properties of C₆₀‐bonded polystyrene were better than those of polystyrene initiated with CCl₄. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3001–3004, 2002     

Synthesis and Evaluation of Hybrid Structures Composed of Two Glucosylceramide Synthase Inhibitors

Glucosylceramide metabolism and the enzymes involved have attracted significant interest in medicinal chemistry, because aberrations in the levels of glycolipids that are derived from glucosylceramide are causative in a range of human diseases including lysosomal storage disorders, type 2 diabetes, and neurodegenerative diseases. Selective modulation of one of the glycoprocessing enzymes involved in glucosylceramide metabolism—glucosylceramide synthase (GCS), acid glucosylceramidase (GBA1), or neutral glucosylceramidase (GBA2)—is therefore an attractive research objective. In this study we took two established GCS inhibitors, one based on deoxynojirimycin and the other a ceramide analogue, and merged characteristic features to obtain hybrid compounds. The resulting 39‐compound library does not contain new GCS inhibitors; however, a potent (200 nm ) GBA1 inhibitor was identified that has little activity toward GBA2 and might therefore serve as a lead for further biomedical development as a selective GBA1 modulator.     

纳米ZSM-5的合成

纳米ZSM-5的合成方法以水热体系和清液体系合成为主。文章总结了纳米ZSM-5合成的影响因素以及有关特殊结构的合成。低温老化,较高的碱度以及较高的模板剂用量,晶种的添加,适宜的硅铝源等都有助ZSM-5晶粒尺寸的降低。通过改变合成条件,添加表面活性剂以及矿化剂,合成出具有纳米片层以及纳米纤维等特殊形貌的纳米ZSM-5。     

纳米复合水性仿幕墙外墙涂料

介绍了纳米复合水性仿幕墙外墙涂料的原料选择及配方设计，探讨了主要原材料对产品性能的影响以及关键制备工艺；研制出了一种具有高性能、高装饰性的纳米复合水性仿幕墙外墙涂料。     

Synthesis of polyurethane elastomers hypercross-linked by partially hydrated polyhydroxylated C60

Utilization of polyhydroxylated C₆₀ (fullerenols) in a condensation reaction with diisocyanated oligo(tetramethylene oxide) led to the successful fabrication of elastomeric poly (urethane-ether) networks. These polymer networks exhibit interesting thermal behavior at low temperatures, improved tensile strength and elongation at ambient temperatures, and enhanced thermal mechanical stability at high temperatures, as compared with those of the parent linear polyurethane analogues; or with the conventional oligo (tetramethylene oxide)-derived polyurethane elastomers cross-linked by trihydroxylated reagents (1,I,1-trismethylol propane) or tetrahydroxylated reagents (pentaerythritol). The presence of a limited quantity of water molecules in the condensation reaction of fullerenols with diisocyanated prepolymers modified the physical properties of the resulting elastomeric products with a notable increase in tensile strength, modulus, and Ts over those of elasotmers prepared under anhydrous conditions. These water molecules contributed effectively to the increase of the number of cross-linking centers during the reaction.     

Synthesis of C60 end-capped poly(4-diphenylaminostyrene): Addition of poly(4-diphenylaminostyryl)lithium to C60

The covalent modification of fullerene-C₆₀ (C₆₀) with poly(4-diphenylaminostyrene) (PDAS) was examined to explore the possibility of preparing new materials for effective photovoltaic cells. The high nucleophilicity and small steric hindrance of the PDAS carbanion is a very important factor in the addition of poly(4-diphenylaminostyryl)lithium (PDASLi) to C₆₀. C₆₀ end-capped PDAS (C₆₀-PDAS), consisting of one PDAS molecule bonded to one C₆₀ molecule at the polymer chain-end, was successfully prepared from the PDASLi/N,N,N’,N’-tetramethylethylenediamine system and C₆₀. UV/vis and photoluminescence spectra suggest that C₆₀-PDAS has considerable potential for the preparation of effective photovoltaic cells.     

有机-无机纳米复合涂料的制备、结构和性能

近年来,有机-无机(O/I)纳米复合涂料发展迅速,已成为涂料领域最活跃的研究方向之一,其制备方法可以分成三类:纳米粒子填充法、溶胶-凝胶法和自组装法。本文系统讨论了上述三种路线的制备方法以及结构和性能的影响因素,同时给出了一些评价和建议。     

纳米光触媒的合成工艺及其应用研究

以硫酸氧钛为原料通过常温水解沉淀及水热处理制备了纳米光触媒乳液.考察了水解pH值、稳定剂、氧化剂、热处理温度及热处理时间等条件对该乳液的光催化性能的影响.XRD和TEM检测结果表明:光触媒乳液中纳米TiO2颗粒晶体结构为锐钛型,平均粒径为10 nm.光催化活性评价表明:当水解溶液的pH值=8,以柠檬酸为稳定剂,在100 ℃下水热处理6 h后获得的纳米光触媒乳液具有最佳光催化活性.     

水热法制备纳米二氧化钒粉体

以五氧化二钒和无水亚硫酸钠为原料,采用水热法制备纳米VO2粉体。系统地探讨了p H、填充度、反应温度、无水亚硫酸钠用量对VO2产品制备工艺的影响,采用化学法、X射线衍射仪(XRD)、扫瞄电子显微镜(SEM)和差示热扫描仪(DSC)对产品的价态、物相、形貌进行了分析。结果表明,在p H=3、填充度为0.7、物质的量比为n(V2O5)∶n(Na2SO3)=1∶1.2、温度250℃下水热反应24 h,所得到的初产品经氢氧化钠溶液纯化1 h后,质量分数达到98.5%,总产率为85.4%。产品为纯度高的B相VO2,经800℃热处理2 h后由B相转变为M相,热处理后产品的相变点为69.0℃。     

纳米二硫化钼的合成与性能研究

以钼酸钠（Na2MoO4）、水合肼（N2H2·H2O）、硫代乙酰胺（CH3CSNH2）和盐酸（HCl）为原材料。利用气泡液膜法合成工艺制备纳米级的二硫化钼。采用XPS、SEM、激光粒度分析仪对合成产物的组成、包覆效果、形貌和粒径进行了表征。测定了合成产物的表面能。结果表明采用气泡液膜法合成工艺制备得到油酸包覆、分散均匀、无团聚、平均粒径为70nm的纳米级的二硫化钼,且合成产物粒子表面能大大降低,仅为5．286mN／m。     

聚合物复合材料中的纳米杂化串晶研究

聚合物纳米复合材料界面结晶处常形成纳米杂化串晶(NHSK)。文章综述了近年来纳米杂化串晶结构的研究进展,介绍了NHSK形成的方法和影响NHSK形成和生长的因素,并对NHSK的形成机理进行了深入探究。最后,介绍了NHSK的应用,并对其发展趋势做了展望。     

Synthesis of telechelic C60 end‐capped polymers under microwave irradiation

Bromo‐Double‐Terminated polystyrene (Br‐PSt‐Br) and poly(methyl methacrylate) (Br‐PMMA‐Br) with predesigned molecular weight and narrow polydispersity were prepared by atom transfer radical polymerization (ATRP) using the initiating system aa′‐dibromo‐p‐xylene(DBX) / CuBr/2,2′‐bipyridine(bipy). The precursor bromo‐terminated polymers were subsequently functionalized with fullerene C₆₀ using CuBr/bipy as the catalyst system under microwave irradiation (MI). The telechelic C₆₀ end‐capped products were characterized by gel permeation chromatography (GPC), UV‐vis, FT‐IR, TGA, DSC, ¹H NMR, and ¹³C NMR. The results showed that microwave irradiation could significantly increase the rate of fullerenation reaction, and the physical properties and structure of the C₆₀ end‐capped polymers are not modified by the use of the microwave. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 828–834, 2006