富勒烯-衣康酸共聚物的合成及其润滑性能

通过自由基聚合，合成了一种新型纳米级富勒烯－衣康酸共聚物，其易溶于水，甲醇、丙酮、四氢呋喃等溶剂。采用FTIR、UV－240、GPC等进行结构表征，TEM分析表明其在水溶液中形貌为理想的球形，平均粒径约为48nm，四球机试验测试结果表明，一定浓度的富勒烯共聚物可有效提高水基液的承载能力，增强抗磨能力，对其磨斑表面采用扫描电子显微镜分析，结果表明，磨痕变浅，磨斑减小，有效降低了磨损。     

纳米C60/C70-丙烯酸(酯) 共聚物的合成及性能

将纳米C60／C70与丙烯酸(酯)单体在引发剂作用下共聚，合成得到C60／C70-丙烯酸(酯)共聚物。对该共聚物的结构进行了红外光谱和荧光光谱分析，探讨了有富勒烯参与的聚合反应机理和共聚物结构。将该共聚物用有机胺中和成盐，使其水性化，制得水溶性纳米C60／C70-丙烯酸(酯)高分子成膜材料，对其成膜性能进行了分析测试。发现C60／C70对丙烯酸(酯)聚合物具有独特的成膜改性功能。     

富勒烯-甘氨酸衍生物的制备

通过有机化学的方法合成了一种新型纳米级富勒烯-甘氨酸衍生物,该衍生物极易溶于水、DMSO、四氢呋喃等极性溶剂。通过红外光谱、核磁共振、TEM等分析手段对衍生物的组成和结构进行了表征。TEM分析表明,它在水溶液中形貌为理想的球形,平均粒径约为18nm。体外抗癌活性测试结果表明,该衍生物对人体的骨癌等癌细胞均具有很好的抑制能力,其抑制能力与衍生物的浓度和光照强度有关。研究了该衍生物的抗癌机理。     

3-甲基吗啉-2,5-二酮与ε-己内酯共聚物的制备与表征

以辛酸亚锡为催化剂,合成了3-甲基吗啉-2,5-二酮(MMD)与ε-已内酯(ε-CL)的共聚物,并用FT-IR、1HNMR、DSC、粘度测定等分析方法对共聚物进行了表征.结果表明,MMD能很好地与ε-己内酯进行共聚,且共聚物的性能可以根据投料比例的不同在很大范围内进行调节.     

苯乙烯-马来酸交替共聚物的合成及水溶液性质

以过氧化苯甲酰为引发剂,采用沉淀聚合法合成了苯乙烯-马来酸酐交替共聚物,用核磁共振（13C-NMR）,红外光谱（IR）和凝胶渗透色谱（GPC）对共聚物进行了表征。利用苯乙烯-马来酸酐交替共聚物的水解反应制备了苯乙烯-马来酸交替共聚物,并对其水溶液性质进行了研究。结果表明,苯乙烯-马来酸交替共聚物为二元羧酸,且随着共聚物...     

富勒烯-赖氨酸衍生物的合成及其体外抗癌活性研究

合成了一种新型纳米级富勒烯-赖氨酸衍生物,通过红外光谱、核磁共振、TEM等分析手段对衍生物的组成和结构进行了表征,TEM分析表明其在水溶液中的形貌为理想的球形,平均粒径约为30nm;研究了该衍生物的抗癌机理,体外抗癌活性测试结果表明,该衍生物对人体的骨癌等癌细胞均具有很好的抑制能力,其抑制能力与衍生物的浓度和光照强度有关.     

聚6-氨基己酸-β-丙氨酸的合成及降解行为研究

采用熔融缩聚法制备了一种新型可降解的6-氨基己酸(6N)和β-丙氨酸(βA)的二元共聚物(PAA),并研究了该共聚物的性能。采用红外光谱分析(FT-IR)、X射线衍射分析(XRD)、差示扫描量热分析(DSC)、热重分析(TGA)等手段对其结构进行了表征,结果表明,所合成的材料是2种单体的聚酰胺共聚物;随β-丙氨酸含量的增加,共聚物的结晶度、熔融温度呈先减小后增大的趋势,而分解温度呈依次减小的趋势,当共聚物中2种单体摩尔比为1∶1时,其为无定形共聚物。共聚物在去离子水中的降解实验结果表明,材料具有良好的降解性能;不同单体比例合成的共聚物中,共聚物的降解速率与共聚物的结晶度成反比,当聚合物中2种单体摩尔比为1∶1时,聚合物的降解速度最快,2周后几乎完全降解;整个降解过程中,降解液的pH值都维持在相对稳定的水平。在环保方面,该材料可望有良好的应用前景。     

1-丁烯共聚弹性体的微观结构表征

采用红外光谱仪、差示量热扫描仪、偏光显微镜等对负载钛催化体系合成的1-丁烯/1-己烯共聚物进行了微观结构表征.结果表明,共聚样的组成由投料比决定且随反应时间变化不大,1-己烯结构单元的引入可以有效的打破聚合物中1-丁烯单元链节的结晶性,其结晶度随着1-己烯含量的增加逐渐降低.偏光显微镜照片显示随1己烯含量增加,共聚物的球晶逐渐变小,且最终消失.     

8-羟基喹哪啶-丙烯酸-镓(Ⅲ)与苯乙烯共聚物的合成和性能

将8-羟基喹哪啶-丙烯酸-镓(Ⅲ)的三元配合物单体与苯乙烯共聚后得到一种含镓(Ⅲ)的共聚物。通过红外光谱、元素分析、紫外光谱、广角X射线衍射等方法对三元配合物和共聚物的组成进行了表征。测试共聚物的荧光光谱，发现共聚物的氯仿溶液在493nm处能发出较强的荧光，共聚物膜在473nm处能光致发光。DSC分析表明共聚物具有良好的耐热性。广角X射线衍射结果表明共聚物为非晶结构。     

丙烯酸-丁烯醛共聚物的合成

采用水溶液共聚法合成了丙烯酸-丁烯醛共聚物,使用IR、^13C-NMR及DSC表征了共聚物的结构.用称量法测定共聚合反应的转化率和反应速率,乌氏黏度计测定共聚物的特性黏数[η],并用其相对表征共聚物分子量大小.重点研究了共聚合条件对共聚合反应的转化率、反应速率及所得共聚物分子量的影响.实验结果表明,引发剂用量、单体浓度及聚合温度对共聚合反应和共聚物的分子量均有很大影响;丁烯醛对共聚合反应有抑制作用。     

Improved wear properties of magnesium matrix composite with the addition of fullerene using semi powder metallurgy

The present study aims to fabricate fullerene (C60) reinforced magnesium matrix composite via semi powder metallurgy in hot press system under high purity argon atmosphere. Improvement of wear resistance of pure magnesium with the addition of fullerene is also aimed with this study. Hardness and wear tests at room temperature were performed to investigate the mechanical effect of fullerene nanoparticles. Microstructures of fabricated composites were characterized using Scanning Electron Microscope (SEM). Results clearly show that hardness performance was improved up to 0.5 wt. % fullerene addition directly. A uniform distribution was also achieved according to the mapping and line EDX analysis for the lower content of fullerene. Agglomeration of fullerene was observed for 1 wt. % reinforced composite. Wear performances of pure magnesium were also improved when harder fullerene reinforcements incorporated into the matrix. Abrasion and oxidation were main wear mechanism for unreinforced and fullerene reinforced composites. Enhancement of hardness and wear performances might be attributed to the high specific surface area of fullerene and achievement of uniform distribution of reinforcement in magnesium matrix.     

Synthesis of a fullerene/expanded graphite composite and its lubricating properties

A fullerene/expanded graphite composite, in which fullerene crystals were incorporated into the expanded graphite interspaces, was prepared by chemical and thermal treatments and its lubricating properties in commercial grease were investigated. Expanded graphite, which was synthesized from graphite by oxidizing by KMnO₄ in 98% H₂SO₄ containing NaNO₃ and by heating at 400 °C for 3 min, and fullerene were placed in a stainless steel tube, and were heated in a furnace under vacuum at 600 °C for 2 weeks. The fullerene/expanded graphite composite obtained was characterized by X-ray diffraction analysis (XRD), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM). XRD and FT-IR analyses showed that crystalline fullerene was present in the material and SEM images confirmed that it existed in the expanded graphite interspaces. The composite was blended with a commercial grease, and its lubricating properties were investigated using a four-ball lubricant tester. These properties were evaluated by measuring the wear scar diameter and wear volume loss of the test ball. The combination of composite and grease provided a better lubricating performance than that of pure graphite and grease.     

INFLUENCE OF DESIGN AND OPERATIONAL PARAMETERS ON YIELD OF FULLERENES

Fullerene production by arc-discharge method using graphite electrodes has been studied with respect to influence of different design and operational parameters on fullerene yield in a constant arc fullerene reactor. The design parameters like reactor length, diameter, heat transfer area and operational parameters like voltage, current, pressure, coolant flow rate, graphite evaporation rate and electrode diameter etc. have been experimentally studied in detail to establish a relationship between these parameters and fullerene yield. All the parameters affecting the yield have been correlated by dimensional analysis and an equation to calculate the fullerene yield is derived. It was observed experimentally as well as by dimensional analysis that many favorable parameters for getting good yield are linked with other parameters which also get changed if the favorable parameters are changed and thus it is difficult to make a substantial change in the yield of fullerenes.  The relationship established between the yield and parameters is however useful in optimising fullerene yield in a reactor and also helpful in designing a futuristic fullerene reactor of improved yield and productivity. The fullerene yield from different designs of reactors is obtained in the range of 4% to 20%.     

INFLUENCE OF DESIGN AND OPERATIONAL PARAMETERS ON YIELD OF FULLERENES

ABSTRACT

Fullerene production by arc-discharge method using graphite electrodes has been studied with respect to influence of different design and operational parameters on fullerene yield in a constant arc fullerene reactor. The design parameters like reactor length, diameter, heat transfer area and operational parameters like voltage, current, pressure, coolant flow rate, graphite evaporation rate and electrode diameter etc. have been experimentally studied in detail to establish a relationship between these parameters and fullerene yield. All the parameters affecting the yield have been correlated by dimensional analysis and an equation to calculate the fullerene yield is derived. It was observed experimentally as well as by dimensional analysis that many favorable parameters for getting good yield are linked with other parameters which also get changed if the favorable parameters are changed and thus it is difficult to make a substantial change in the yield of fullerenes. The relationship established between the yield and parameters is however useful in optimising fullerene yield in a reactor and also helpful in designing a futuristic fullerene reactor of improved yield and productivity. The fullerene yield from different designs of reactors is obtained in the range of 4% to 20%.     

Optical and electronic properties of fluorene/thiophene/benzothiadiazole pseudorandom copolymers for photovoltaic applications

A new family of 9,9-bisalkylfluorene (F)/thiophene (T)/benzothiadiazole (B) π-conjugated copolymers for organic solar cells is reported. The structure of the reported copolymers is pseudorandom: in turn each F, T, B monomer unit is alternated to the other randomly distributed two units. Voltammetric, UV–visible, and photoluminescence measurements have been carried out to assess the optical and electronic properties of the synthesized materials. The occurring of photoinduced charge transfer towards a fullerene electron acceptor was investigated by photoluminescence quenching and light-induced electron spin resonance experiments. The copolymer having alternating thiophene monomer units and randomly distributed fluorene and benzothiadiazole units exhibits the most promising characteristics; the photophysic study shows that such polymer/fullerene blend could represent a novel and cheaper material to be used as convenient donor–acceptor system for polymer solar cells.     

表面活性剂对纳米氧化锌减摩抗磨性能的影响

为提高纳米氧化锌在润滑油中的摩擦磨损性能和成膜性能,采用均匀沉淀法在合成过程中加入表面活性剂(十六烷基三甲基溴化铵(CTAB))制备了平均粒径约为20~30 nm的纳米氧化锌,并利用SEM、TEM、XRD等方法对制备材料的组织和相组成进行了表征。同时,利用四球摩擦磨损试验机考察纳米氧化锌对润滑油摩擦磨损性能的影响。结果表明:在载荷392 N时,最佳添加量(质量分数)为0.5%,平均摩擦系数降低了35%,磨斑直径下降了11%;利用CTAB修饰后平均摩擦系数降低了70%,磨斑直径下降了40%。在不同载荷下平均摩擦系数出现先增高后下降的趋势。钢球摩擦表面的形貌分析表明,添加CTAB后的纳米氧化锌润滑油,钢球磨损表面犂沟深度最浅,宽度最小。利用CTAB合成的纳米氧化锌具有良好的减摩抗磨性能,可以大大降低机械零件的摩擦力。     

Hierarchical nanomorphologies promote exciton dissociation in polymer/fullerene bulk heterojunction solar cells

PTB7 semiconducting copolymer comprising thieno[3,4-b]thiophene and benzodithiophene alternating repeat units set a historic record of solar energy conversion efficiency (7.4%) in polymer/fullerene bulk heterojunction solar cells. To further improve solar cell performance, a thorough understanding of structure-property relationships associated with PTB7/fullerene and related organic photovoltaic (OPV) devices is crucial. Traditionally, OPV active layers are viewed as an interpenetrating network of pure polymers and fullerenes with discrete interfaces. Here we show that the active layer of PTB7/fullerene OPV devices in fact involves hierarchical nanomorphologies ranging from several nanometers of crystallites to tens of nanometers of nanocrystallite aggregates in PTB7-rich and fullerene-rich domains, themselves hundreds of nanometers in size. These hierarchical nanomorphologies are coupled to significantly enhanced exciton dissociation, which consequently contribute to photocurrent, indicating that the nanostructural characteristics at multiple length scales is one of the key factors determining the performance of PTB7 copolymer, and likely most polymer/fullerene systems, in OPV devices.     

Radical-scavenging Ability of Hydrophilic Carbon Nanoparticles: From Fullerene to Its Soot

We have recently developed a facile synthetic method for highly water-soluble fullerene, so-called fullerenol, for the treatment of fullerene with hydrogen peroxide. This method was applied to fullerene soot to yield the corresponding new hydrophilic carbon materials, and the obtained products were subjected to infrared spectroscopy and elemental analysis. The DLS particle size analysis demonstrated the relatively high dispersion of hydrophilic fullerene soot with a diameter of ?70 nm in water, while the hydrophilic activated carbon obtained by the same treatment showed the larger aggregation with diameters of 200 and 970 nm. The surface analysis using FE-SEM showed the difference in morphology between fullerene soot and activated carbon as well as between before and after hydrophilic treatment of the soot with hydrogen peroxide. Moreover, this hydrophilic fullerene soot exhibited high antioxidant activity (%AOA) up to 87% compared with fullerenol C₆₀(OH)₃₆ (54%) and C₆₀ (50%) evaluated by β-carotene bleaching method.     

Thermosensitive Y-shaped micelles of poly(oleic acid-Y-N-isopropylacrylamide) for drug delivery

A novel thermosensitive amphiphilic copolymer comprised of two hydrophobic poly(oleic acid) (POA) segments and one hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) segment was designed and synthesized. The structure of the copolymer was confirmed as Y-shaped by FTIR, 1H NMR, and SEC-MALLS analysis. A cytotoxicity study shows that the P(OA-Y-NIPAAm) copolymer exhibits good biocompatibility. The copolymer may self-assemble into micelles in water, with the hydrophobic POA segments at the cores of micelles and the hydrophilic PNIPAAm segments as the outer shells. The resulting micelles demonstrate temperature sensitivity with a lower critical solution temperature (LCST) of 31.5 degrees C and a critical micelle concentration (CMC) of 12.6 mg L(-1). Transmission electron microscopy (TEM) shows that the micelles exhibit a nanospheric morphology within a narrow size range of approximately 10-30 nm. A study of controlled release reveals that the self-assembled micelles have great potential as drug carriers.