Formation of BN from BCNO and the development of ordered BN structure: I. Synthesis of BCNO with various chemistries and degrees of crystallinity and reaction mechanism on BN formation

We synthesized BCNO compounds and investigated how the synthesis conditions impact i) BCNO formation, their chemistry and degree of crystallinity, and ii) BN formation from BCNO and its structural ordering. Heating boric acid (H₃BO₃) and melamine (C₃H₆N₆) mixture yields intermediate amorphous BCNO compound. Increasing the synthesis temperature, and H₃BO₃ to C₃H₆N₆ ratio promote BN formation and its structural ordering. We propose a possible reaction mechanism for BN formation from H₃BO₃ and C₃H₆N₆ mixture and we explain the observations based on thermodynamic and kinetic considerations. An increase in synthesis temperature promotes BN formation since the reactions are endothermic. An increase in H₃BO₃ to C₃H₆N₆ ratio promotes BN formation since theoretical BN formation temperature decreases with the above ratio. Furthermore, it enhances material transfer and mobility of the BN layer by forming B₂O₃ phase. We also propose a processing-structure correlation map that can help determining experimental conditions for single-phase amorphous BCNO synthesis.     

Synthesis and application of new fullerene derivative

A novel fullerene–maleic anhydride copolymer is synthesized via radical polymerization. It is soluble in polar solvents such as water, dimethyl sulfoxide, tetrahydrofuran, and so forth. The product is characterized by FTIR, UV–visible, and GPC. Transmission electron microscope analysis shows that it presents an ideal spherical shape in water with an average particle diameter of about 36 nm. Four‐ball tests show that the addition of a certain concentration of the fullerene copolymer to the base stock (2 wt % triethanolamine and 0.5 wt % Alkylpolyoxyalkylene Phosphate Zinc (OPZ) aqueous solution) can effectively raise the load‐carrying capacity (P_B value) and raise the antiwear ability. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2182–2185, 2005     

催化反应精馏技术连续制备乙酸乙酯

在直径３０ｍｍ的催化反应精馏塔中进行合成乙酸乙酯的研究，考察了酸醇比、进料流量、回流比、进料位置等因素对过程的影响，在本实验最优条件下，塔顶可获得酯含量大于９４％的产品。     

A selective reaction of polyhydroxy fullerene with cycloaliphatic epoxy resin in designing ether connected epoxy star utilizing fullerene as a molecular core

A novel ether connected epoxy star like polymer was synthesized by selective reaction of water soluble polyhydroxy fullerene (fullerenol) with a commercial grade cycloaliphatic epoxy resin (CY-230, Ciba Geigy) in heterogeneous medium at ambient alkaline condition using tetrabutylammonium hydroxide as phase transfer catalyst. The reaction went well in such conditions and the hydroxy groups of fullerenol underwent selective nucleophilic addition reaction with polar carbonyl groups of the epoxy resin with the formation of a hemiketal. The progress of the reaction was monitored by FTIR analysis of the product formed. The disappearance of characteristic FTIR bands of fullerenol (at 1593.2, 1381.2, and 1068 cm⁻¹) and the typical carbonyl peak (at 1725 cm⁻¹) of parent epoxy resin and also changes of broad hydroxy peak (at 3431 cm⁻¹) of fullerenol into a sharp peak (at 3396.6 cm⁻¹, indicating reduced hydrophilicity) in the reaction product clearly demonstrated the chemical attachment of the epoxy units to the fullerene core. Multiple epoxy units (about 8-10) were attached to fullerene core. Non-reactivity of fullerenol towards DGEBA epoxy resin (LY 556 Ciba Geigy) in similar conditions further supports our result. The thermal properties of the product were influenced by the presence of fullerenol and exhibits higher thermal stability compared to parent epoxy. A probable reaction mechanism for the reaction has also been discussed.     

两种富勒烯二加成受体材料的合成

合成了两种聚合物光伏电池的电子受体材料,并进行了结构和性能表征。提高了其LUMO能级,用于聚合物光伏电池有望提升器件的开路电压。     

丙二酸亚异丙酯的单取代Mannich反应

研究了丙二酸亚异丙酯与脂肪族胺的单取代曼尼希反应，通过对曼尼希碱的IR、UV、^HNMR及元素分析表征了其结构，发现其生成的曼尼希碱主要以内盐式存，改进丙二酸亚异丙酯的合成条件，使产率达到82.8%.     

Effect of elastic deformations on direct polymorphic transformations in BN under pressure

This paper gives an investigation of the effect of shear deformation on direct transitions in BN under pressure. The transition of a hexagonal (graphite-like) phase h-BN into a cubic (“sphalerite”) c-BN through the intermediate rhombohedral phase r-BN, at a pressure P = 3.0 GPa, is shown. With shear deformation applied, the mechanism of h-BN transformation into the hexagonal (wurtzite) phase w-BN changes, and the following planes are parallel in the phases: for P = 5.0 GPa and deformation ε = 0° (001)_h|| (001)_w; and for P = 5.0 GPa and deformation ε ? 7.2 (001)_h|| (100)_w. The shear deformation at 6–17 GPa leads to the reverse transition of w-BN to h-BN and the observed orientation relationship is different from the one occurring at the thermal transformation of w-BN to h-BN (T ? 1600 K) at a pressure P = 0.1 MPa.     

高效聚烯烃阻燃剂BN 451的合成新工艺

报道了一种四步法合成高效聚烯烃阻燃剂BN 451的新工艺,讨论了合成工艺务件对产率的影响情况,确定了最佳的合成条件,并对产品进行表征.红外谱图分析表明:存在2994、2957、2880、1438、1394、1338 cm-1以及1761、1722 cm-1等处目标产物的特征吸收峰;元素分析表明其实测值与理论值基本一致,进一步证明实验终产物即为目标产物.     

酸性青莲S4BN的合成

以乙基苄基苯胺为主要原料,经磺化,缩合后,氧化成醇体与Ｎ、Ｎ－二乙基苯胺等缩合,再氧化生成目标产物。     

Grignard试剂偶联法合成辅酶Q类化合物

以Grignard试剂偶联反应为构建C—C键的关键反应,由2,3,4,5-四甲氧基甲苯(1)出发,经过溴化、Grignard试剂制备、偶联、氧化等4步反应,成功地合成了辅酶Q2(6a)、Q4(6b)以及Q9(6c),反应总收率分别为66.1%、62.1%和65.1%,为辅酶Q类化合物的工业化合成提供了实验依据。     

氮化硼纤维先驱体聚合物的合成及其表征

以三氯化硼与氯化铵为基础原料合成了三氯环硼氮烷（TCB）,然后将TCB和三氯化硼分别与甲胺反应制得TCB的衍生物（CH3NH）3N3B3H3和B（NHCH3）3单体,将这些衍生物混合后在一定条件下进行缩合反应得到氮化硼先驱体。从合成方法、反应机理及其产物的结构性能表征等方面研究了氮化硼陶瓷纤维的先驱体,并且用IR、NMR、EA．XRD及DSC等表征方法对先驱体的结构、成分及性能进行了分析。结果表明：先驱体中含有B、C、N、H元素,存在CH3、B-N、N—H、G—H、BN六元环等结构单元。最后,对此先驱体进行了试纺丝,并用扫描电镜观察了所得纤维的形态。     

前驱体法制备氮化硼纤维的研究进展

综述了由前驱体法制备氮化硼纤维的合成方法，主要介绍了由有机前驱体制备氮化硼纤维的合成工艺路线及技术关键，并介绍了各类方法制得的纤维的性能。     

Synthesis of monoclinic Celsian from Coal Fly Ash by using a one-step solid-state reaction process

Monoclinic (Celsian) and hexagonal (Hexacelsian) Ba_1?xSr_xAl₂Si₂O₈ solid solutions, where x = 0, 0.25, 0.375, 0.5, 0.75 or 1, were synthesized by using Coal Fly Ash (CFA) as main raw material, employing a simple one-step solid-state reaction process involving thermal treatment for 5 h at 850–1300 °C. Fully monoclinic Celsian was obtained at 1200 °C/5 h, for SrO contents of 0.25 ≤ x ≤ 0.75. However, an optimum SrO level of 0.25 ≤ x ≤ 0.375 was recommended for the stabilization of Celsian. These synthesis conditions represent a significant improvement over the higher temperatures, longer times and/or multi-step processes needed to obtain fully monoclinic Celsian, when other raw materials are used for this purpose, according to previous literature. These results were attributed to the role of the chemical and phase constitution of CFA as well as to a likely mineralizing effect of CaO and TiO₂ present in it, which enhanced the Hexacelsian to Celsian conversion.     

Synthesis of attractants for oriental fruit flyDacus dorsalis Hendel using a catalytic organocopper coupling reaction

A general synthetic approach to various catechol derivatives was developed using a copper-catalyzed cross-coupling reaction of 1,2-dimethoxy-4-brornomethyl, 1-ethoxy-2-methoxy-4-bromomethyl- and 2-ethoxy-1-methoxy-4-bromomethylbenzenes with Grignard reagents. Dilithium tetrachlorocuprate was an acceptable catalyst in the dimethoxy series, whereas copper(I) iodide in THF-HMPA was a superior catalyst in all cases due to decreased side reactions, i.e., reduction and reductive coupling. Methyl-substituted analogs of methyl eugenol, a potent attractant of Oriental fruit fly,Dacus dorsalis Hendel, were synthesized by this method and evaluated for attractancy in field tests.On leave from the Institute of Organic Chemistry of the Armenian Academy of Sciences, Yerevan, Armenia; author to whom correspondence should be addressed.Presented at the 204th ACS National Meeting, Washington, D.C., 1992. This paper reports the results of research only. Mention of a proprietory product does not constitute an endorsement of this product by the USDA.     

Synthesis of a water‐soluble fullerene derivative nanoball and its biological activity

A novel fullerene–acrylamide copolymer was synthesized via radical polymerization. It is soluble in polar solvents such as water and dimethyl sulfoxide. The product was characterized by FTIR, UV–vis, and GPC. TEM analysis showed that the average particle diameter was about 46 nm. The in vitro antitumor activity of the fullerene–acrylamide derivatives was tested, and the results showed that the novel fullerene–acrylamide derivatives exhibited better antitumor activity in vitro against bone tumor cells. The cytotoxicity against the tumor cell mechanism of the fullerene copolymer nanoball was studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Synthesis of functional polymers containing distyrylthiophene moiety using the heck reaction

Summary Polymers containing a trans, trans-2,5-thienylenevinylene-1,4-phenylenevinylene moiety were prepared by palladium-catalyzed polycondensation. Couples of 2,5-divinylthiophene derivatives 1 with p-dihalobenzenes 2 successfully produced the expected polymers 5, whereas couples of 2,5-dihalothiophene derivatives 3 with p-divinylbenzene 4 gave only oligomers due to the homo-coupling reaction of 3. Synthesis of a thermotropic liquid crystalline polymer having trans, trans-2,5-distyrylthiophene skeletons as mesogen was also investigated by use of the polyconcensation between 1 and bis(p-iodophenyl) compounds 6 that concurrently have flexible segments.     

Synthesis of biodiesel fuel from safflower oil using various reaction parameters

Biodiesel fuel is gaining more and more importance because of the depletion and uncontrollable prices of fossil fuel resources. The use of vegetable oil and their derivatives as alternatives for diesel fuel is the best answer and as old as Diesel Engine. Chemically biodiesel fuel is the mono alkyl esters of fatty acids derived from renewable feed stocks like vegetable oils and animal fats. Safflower oil contains 75-80% of linoleic acid; the presence of this unsaturated fatty acid is useful in alleviating low temperature properties like pour point, cloud point and cold filter plugging point. In this paper we studied the effect of various parameters such as temperature, molar ratio (oil to alcohol), and concentration of catalyst on synthesis of biodiesel fuel from safflower oil. The better suitable conditions of 1:6 molar ratio (oil to alcohol), 60 degrees C temperature and catalyst concentration of 2% (by wt. of oil) were determined. The finally obtained biodiesel fuel was analyzed for fatty acid composition by GLC and some other properties such as flash point, specific gravity and acid value were also determined. From the results it was clear that the produced biodiesel fuel was with in the recommended standards of biodiesel fuel with 96.8% yield.