笼型单乙烯基倍半硅氧烷的合成及表征

用环戊基三氯硅烷合成不完全缩合三羟基硅氧烷［(C₅H₉)₇Si₇O₉(OH)₃］,再以乙烯基三氯硅烷和不完全缩合三羟基硅氧烷为原料,以四氢呋喃和三乙胺为混合溶剂,通过“顶角-戴帽”反应合成了笼型单乙烯基倍半硅氧烷,即1,3,5,7,9,11,13-七环戊基-15-乙烯基笼型倍半硅氧烷(VinylPOSS)。利用FTIR、¹H NMR、²⁹Si NMR、¹³C NMR、元素分析、WAXD和TGA表征了VinylPOSS的结构及热稳定性。研究结果表明VinylPOSS的产率随着反应时间的增加而提高,当反应时间为10 h时,产率高达90%;其在弱极性溶剂中具有较好的溶解性,5%失重温度为283℃,800℃残留率为56%,具有较高的热稳定性。研究了VinylPOSS和高含氢硅油(HHSF)的反应性,结果表明VinylPOSS能与含氢硅油发生α、β加成反应, 且以β加成为主。     

端乙烯基含硼硅油的合成及性能表征

以二苯基二甲氧基硅烷和噻吩-3-硼酸为原料,四甲基二乙烯基二硅氧烷为封端剂,采用水解-缩聚法合成了一种新型的端乙烯基含硼(B)硅油,并探讨了水用量、反应温度、反应时间、B/Si量之比对聚合反应的影响。光谱分析证实B以B—O和B—O—Si的形式引入到有机硅分子主链中。较佳反应条件为:n_B∶n_(Si)为0. 20,水用量10. 8 g,反应时间4. 5 h,反应温度80℃,此条件制得的产物黏度为3 741 m Pa·s,产率达78. 23%,具有很好的耐热性。     

乙醇羰基化常压气-固相反应的动力学研究

本文对乙醇在微分反应器中用Ni-Pb/C催化剂, 反应温度250 ℃, 压力0.1 MPa, 原料配比为CO/C₂H₅OH/C₂H₅I=2/1/0.1, 接触时间(W/F)3.3 g·h/mmol 的条件下拨基化反应的动力学进行了研究, 生成丙酸乙醋的反应速度方程为:r_EtPr=kP_CO^1.4P_C2H5OH^1.7P_C2H5I^0.1 生成乙醚副反应的反应速度方程为: r_Eth=kP_CO^-0.1P_C2H5OH^1.1P_C2H5I^0.6 反应活化能E=28.9 kJ/mol     

新型层状粘土结构F-T合成催化剂的研制

用FeCl₃·6H₂O和Na₂SiO₃水玻璃共沉淀法制备蒙脱土结构的新型F-T合成催化剂。用XRD、SEM和N₂低温吸附-脱附等方法对催化剂的物相结构进行测定,确认催化剂具有层状结构并有较高的比表面积。催化剂经过预处理,F-T合成在浆态床反应器中进行,反应条件：270 ℃,0.5 MPa,气流量34.5 mL·min^-1,n(H₂)∶n（CO）=2∶1,反应时间6 h。产物分析得知,C₉～C₂₅烃类的选择性达到90%以上,使ASF分布规律发生正偏移。     

海藻酸钠-聚乙烯醇共固定化细胞脱除燃料油中的有机硫

从孤岛油田油浸土壤中筛选得到能降解二苯并噻吩(DBT)的红平红球菌DS-3, 对其进行了固定化研究.选取海藻酸钠(SA〖DK〗)-聚乙烯醇(PVA)为包埋固定化载体, 以1 mmol·L^-1二甲基亚砜培养菌体, 固定化最佳操作条件为4℃交联, 8%PVA和2%SA混合, 细胞在胶液中的浓度为0.1 g·ml^-1, 氯化钙含量为2%,此时固定化细胞不但具有良好的脱硫性能, 而且脱硫重复性好, 其寿命可以达到250 h以上.固定化细胞在3次循环后能使模拟柴油中的DBT含量从0.5 mmol·L^-1降至0.011 mmol·L^-1, 总脱硫率达到93％, 平均脱硫效率约为0.225 mg DBT· (g DCW)^-1·h^-1.同样条件下能将精制柴油的硫含量由340 mg·L^-1降到42 mg·L^-1, 总脱硫率为87.64%.DS-3能利用醇类、饱和的C₈～C₁₅脂肪烃, 但不能利用环烷烃、芳香烃、小于C₈或大于C₁₅的脂肪烃, DS-3优先利用碳源的顺序是乙醇、葡萄糖和烷烃.脱硫前后的精制柴油经GC-FID分析证实, 固定化细胞对C—S键具特异性, 不降低柴油的热值.     

正硅酸乙酯法乙烯基MQ硅树脂的结构及热性能研究

以正硅酸乙酯,六甲基二硅氧烷和乙烯基二甲基乙氧基硅烷为原料,通过水解缩聚反应制备了乙烯基MQ硅树脂,采用FT-IR、1H NMR、29Si NMR和热失重方法研究了产物结构,并利用Kissinger、Flynn-Wall-Ozawa和Coats-Redfern热分析方法求得了乙烯基MQ硅树脂在最大失重区的热分解动力学方程。     

非化学计量比尖晶石型锂离子电池正极材料的合成与表征

采用阴阳离子复合掺杂,以共沉淀法、超声共沉淀法、Pechini法和高温固相法合成掺杂锰酸锂前驱体,使用三段热处理方式,即650℃预烧、780℃烧结、550℃回火制备掺杂非化学计量尖晶石Li _1.05 Co _0.05 Ni _0.05 Mn _1.9 O _3.9 F _0.1 .通过化学容量分析测定Mn含量和平均价态,用粒度分布、电镜扫描（SEM）、X射线衍射（XRD）、电化学性能测试对产物进行表征.结果表明产物的Mn含量和平均价态与理论值吻合.比较各种合成方法,超声共沉淀法产物的粒径分布最窄、比表面积最小（0.96 m²•g^-1）、晶型完整、衍射强度最大、结晶性能最佳、晶格常数a为0.821 nm、晶粒尺寸L为57.78 nm.经装配电池电化学性能测定,超声共沉淀法产物的初始容量更高,循环性能更稳定,经30次循环后容量衰减仅9.3％.     

负载型二氧化钛光电催化降解苯酚废水的反应动力学

采用浸渍提拉法制备发泡镍载二氧化钛薄膜电极,并以其为工作电极,建立三电极光电催化体系,对该体系降解苯酚的动力学进行了研究.考察了反应液初始pH值、反应物初始浓度、催化剂用量、光辐照强度、外加直流偏压值对光电催化反应速率的影响,采用幂指数方程描述反应动力学,得到方程C=C₀exp(-0.5430 C ^-0.4241 ₀ E ^0.2968 Q ^0.5418 I ^0.5877 t).方程计算值与实验值吻合较好,误差基本在15％以内.     

负载型TiO2 制备及其对茜素红的降解研究

以钛酸四丁酯和正硅酸乙酯为前驱体、冰醋酸为水解抑制剂，用溶胶-凝胶法制备纳米TiO₂/SiO₂复合物。通过X-射线衍射、红外光谱和比表面积仪等测试手段进行了分析，结果表明，纳米TiO₂ /SiO₂粒子焙烧后主要以锐钛型存在，有Ti—O—Si键的产生，复合粒子的比表面积达到389 m²·g^－1。光催化结果表明，n(Ti)∶n(Si)=3和焙烧温度为700 ℃的TiO₂/SiO₂粒子对茜素红溶液的降解性能最好。利用气质联用仪对降解产物进行了分析。     

烯丙氧基聚乙氧基醚阻垢剂的合成与性能

以烯丙氧基聚乙氧基硫酸铵（APES）、马来酸酐（MA）、马来酸酐-丙烯酸共聚物（MA-AA）为原料,水为溶剂,使APES和MA、APES和MA-AA在水溶液中同时进行自由基共聚和接枝共聚,合成了APES接枝MA-AA的APES-MA聚醚型无磷的共聚物阻垢剂,用红外光谱和核磁共振氢谱对共聚物结构进行了表征。探讨了单体配比、温度和用量、黏均分子量对共聚物阻垢性能的影响,结果表明该阻垢剂既具有优异的阻Ca₃(PO₄)₂性能,又有良好的阻CaCO₃特性。温度80℃时,阻垢剂用量5 mg·L^-1,阻Ca₃(PO₄)₂率为98.89％;温度50℃时,用量5 mg·L^-1,阻Ca₃(PO₄)₂率为100.0％,用量25 mg·L^-1,阻CaCO₃率为97.97％。且CaCO₃形成易被清除的松垢,该阻垢剂适用于工业循环冷却水系统。     

Synthesis of vinyl substitute poly(silphenylene‐siloxane) via silyl hydride‐dialkoxysilane process

The synthesis of vinyl‐substituted silphenylene‐siloxane polymer through B(C₆F₅)₃ catalyzed polycondensation of 1,4‐bis(dimethylsilyl)benzene and vinylmethyldimethoxysilane is described. ¹H‐NMR, ²⁹Si‐NMR, and UV spectroscopy indicate that the vinyl groups remain undamaged during the polycondensation reaction. No hydrosilylation side reaction is observed under the reaction conditions. The microstructure of the polymer is not perfectly alternating with a randomization of 20%. The temperature for 5% mass loss is 430°C in inert atmosphere and 417°C in oxidative atmosphere with a residue of 56% at 700°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

溶胶-凝胶法制备镁掺杂的硅灰石化合物及其相形成机理与模型

以硝酸钙、硝酸镁、正硅酸乙酯为先驱体,利用溶胶 凝胶法合成镁掺杂的硅灰石（Mg/CaSiO₃）陶瓷粉体,研究了体系的溶胶 凝胶机理、物相和微观形貌随煅烧温度的变化规律,建立了晶相形成与晶粒长大模型。结果表明：溶胶系统通过正硅酸乙酯的水解与聚合形成凝胶网络,钙离子与镁离子没有参与凝胶网络的形成而是均匀镶嵌在凝胶网络内,固定干凝胶的煅烧时间为1 h,当煅烧温度低于800℃时,主要发生硅氧硅键的断裂,晶相形成少,当煅烧温度高于900℃时,晶相大量生成,颗粒呈球状并因高的比表面能而产生团聚,粉体粒径随着煅烧温度的升高经历了先变小后增大的过程。     

Effects of tris(pentafluorophenyl)borane on the activation of zerovalent-nickel complex in the addition polymerization of norbornene

The effects of B(C₆F₅)₃ on the activation of the Ni(0) and Ni(II) complexes were studied in the polymerization of norbornene. The Ni(0) complex, such as bis(1,5-cyclooctadiene)nickel (Ni(COD)₂ (1), biacetylbis(2,6-diisopropylphenylimmine)(1,3-butadiene)nickel (2), or tetrakis(triphenylphosphine)nickel (5), in combination with B(C₆F₅)₃, was determined to have high activity in the polymerization of norbornene. On the other hand, the Ni(II) complex with B(C₆F₅)₃ did not provide any activity at all under analogous conditions regardless of the structure of the Ni(II) complex. The use of other borane compounds, such as B(C₆H₅)₃, BEt₃, and BF₃ etherate, with Ni(COD)₂ (1) in place of B(C₆F₅)₃ clearly showed the main functions of B(C₆F₅)₃. The high Lewis acidity of B(C₆F₅)₃ enabled it to activate catalytic complexes, thus inducing polymerization. The study of the ¹H, ¹³C, and ¹⁹F NMR spectra of the polynorbornene produced with Ni(COD)₂ (1) and B(C₆F₅)₃, in the presence or absence of ethylene, showed that the initiation of addition polymerization occurred through the insertion of the exo face of the norbornene into the Ni-C bond of the C₆F₅ ligand. A new polymerization mechanism was proposed in norbornene polymerization, wherein the active complex formed from Ni(COD)₂ (1) and B(C₆F₅)₃ acts as a catalyst.     

环价连接性指数与饱和烃沸点的QSPR研究

In this paper, according to the peak numbers of the nuclear magnetic resonance and the Randic embranchment degree (δi) of carbon atom i, the carbon atom‘s environment valence gi is defined as. gi =(ti δi)/2. The gi reflect the characteristic of each carbon atom, and as well as the conjunction detail of the carbon atom with other carbon atoms. So, the gi could distinguish better the chemical environment of each carbon atom in the molecule than δi. A connectivity index of environment valence (^mS) and its athwart index (^mS‘) are proposed based on the adjacency matrix and the carbon atom‘s environment valence gi. Among them, the ^0S and ^0S‘ include the characteristic and the connectivity of each carbon atom, the ^1S and ^1S‘ reflect the second conjunction between carbon atoms. Based on ^0S‘ and N (the number of carbon atom), a new structural parameter symmetry degree (N∝), is defined as. N∝ =[ (^0S‘s^0Sc‘) N]^2/3, and the N∝ reflect the size of the molecule as well as the symmetry of the molecule.The N∝, ^0S and Rn (the biggest ring‘s edge numbers of cycloalkanes) of 474 saturated hydrocarbons (216 paraffins and 258 cycloalkanes) were calculated and correlated with their boiling points. The best regression equation was obtained as follow: In ( 1056 - Tb ) = 6. 9480 - 0. 1040N∝ - 0. 008689^0S -0. 009614Rn 0. 01998Rm^0.5, n=474, R=0. 9989, F=52627, S=5.63K. The model was checked up by the Jackknife‘s method. It should have overall steadiness and could be used for predicting the boiling point of saturated hydrocarbons.     

5-羟基乙酰丙酸的内酯化与缩聚反应

以乙酰丙酸(LA)为原料,通过改进的溴化、水解反应,合成5-羟基乙酰丙酸(5-HLA).基于5-HLA的羟基和羧基,将其作为单体,氯化亚锡为催化剂,经缩聚得到了一种新的脂肪族聚酯——聚5-羟基乙酰丙酸(PHLA).另以BF₃•OEt₂为催化剂,进行5-HLA的内酯化反应,得到了二聚体[BF]1,6,9,13-[BFQ]四氧双螺［4. 2. 4. 2］十四烷-2,10-二酮(又称阿尔泰内酯),它是中药九节菖蒲的化学成分之一.分别用气质联用、核磁、红外、元素分析和凝胶渗透色谱等方法对所得二聚体以及聚合物结构进行表征,讨论了有关的反应机理.     

金属卟啉制备及其电化学特性

引　言燃料电池作为环境友好的发电方式已经得到广泛的认同 ,另外 ,燃料电池也可作为氢化反应器实现化学品与电能共生[1,2 ] .燃料电池的核心是膜电极的制备[3,4 ] .如何降低燃料电池成本是研究者关注的焦点 ,开发新型的非贵金属电催化剂是降低成本的途径之一 .金属卟啉化合物具有高的共轭结构和化学稳定性 ,对分子氧表现出良好的电催化还原活性 ,近年来逐渐成为燃料电池氧还原电催化剂的研究热点 ,以期取代贵金属作为燃料电池和金属空气电池氧还原催化剂 .目前 ,四苯基卟啉 (TPP)、四甲氧基苯基卟啉 (TMPP)是研究较多的卟啉化合物 ,而与…     

Preparation of isotacticity‐rich poly(tert‐butyl vinyl ether) by the cationic polymerization of tert‐butyl vinyl ether with dimethyl[rac‐ethylenebis(indenyl)]zirconium and tri(pentafluorophenyl)borane

tert‐Butyl vinyl ether (tBVE) was polymerized with the catalyst dimethyl[rac‐ethylenebis(indenyl)] zirconium (ansa‐zirconocene) with tri(pentafluorophenyl) borane [B(C₆F₅)₃] as a cocatalyst. The effects of various polymerization conditions, such as the polymerization time, type of polymerization solvent, polymerization temperature, and catalyst concentration, on the conversion of tBVE into poly(tBVE), its molecular weight and molecular weight distribution, and its stereoregularity were investigated. The maximum conversion of tBVE into poly(tBVE) was over 90% at a polymerization temperature of ?30°C with an ansa‐zirconocene and B(C₆F₅)₃ concentration of 3.0 × 10^?7 mol/mol of tBVE, respectively. The number‐average molecular weights of poly(tBVE) ranged from approximately 14,000 to 20,000, with a lower polydispersity index (weight‐average molecular weight/number‐average molecular weight) ranging from 1.48 to 1.77, at all polymerization temperatures. The number‐average molecular weight of poly(tBVE) increased with decreases in the polymerization temperature and catalyst concentration. The mm triad sequence fraction of poly(tBVE) polymerized with ansa‐zirconocene/B(C₆F₅)₃ at ?30°C was much higher than that of poly(tBVE) polymerized with the B(C₆F₅)₃ catalyst at ?30°C, and this indicated that the ansa‐zirconocene/B(C₆F₅)₃ catalyst system affected the isospecific polymerization of tBVE. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

2,2′-联吡啶-1，1′-二氧化物与铜（Ⅱ）的气敏配合物合成及其应用

以无水CuCl₂和2,2′-联吡啶-1,1′-二氧化物为原料,在DMF溶剂中合成了一种气敏配合物［Cu₅(bipy O₂)₆ Cl₈］Cl₂,并经元素分析、紫外光谱、红外光谱和摩尔电导率表征.对该配合物的气敏特性研究表明,该配合物对氨气有一定的敏感性和选择性.工作电压为3 V时,在浓度为0.05～0.40 mmol•L^-1范围,传感器的输出电压产生突跃性变化,从66 mV 增加到1756 mV.当工作电压为2 V时,输出电压随氨气浓度增大产生两次突跃:第1次突跃范围是0.10～0.40 mmol•L^-1,突跃值约为450 mV;第2次突跃范围是0.40～0.60 mmol•L^-1,突跃值约为960 mV.用其制作的传感器在涉氨化工生产的自动控制和氨气泄漏报警方面有一定的应用前景.     

在多孔α-Al2O3陶瓷管上合成 ZSM-35型沸石膜

分别以吡咯烷和正丁胺为模板剂,在多孔α-Al₂O₃陶瓷管（3～5 μm）外表面上原位直接合成出ZSM-35型沸石膜,XRD、SEM对沸石膜进行表征和单组分气体H₂、N₂ 和C₃H₈的渗透性能测试表明：所合成出的沸石膜表面连续完整,晶粒之间互锁生长,沸石膜的厚度约为12～18 μm,具有典型的ZSM-35沸石结构,不同的模板剂对沸石膜的表面形态影响较大;经不同焙烧温度处理的沸石膜, 随着处理温度增高, 沸石膜表面晶粒的排列沿(h 0 0)取向性明显增强;所合成的沸石膜在室温下单组分气体H₂、N₂和C₃H₈渗透率达到10^-6数量级,H₂/N₂ 和H₂/C₃H₈理想分离因数均超过Knudsen扩散.     

Zwitterionic metallocenes via reactions of organozirconocenes with highly electrophilic perfluorophenyl substituted boranes

The highly electrophilic boranes HB(C₆F₅)₂ and B(C₆F₅)₃ are effective reagents for generating a variety of zwitterionic olefin polymerization catalysts. The former borane can be used to incorporate Lewis acid activators into ancillary ligand structures via hydroboration of pendant olefinic functions; alternatively, direct reaction with simple organozirconocenes can lead to a family of hydridoborate stabilized girdle-type zwitterions where charge separation is minimal. The ethylene polymerization activity of these compounds is, in general, poor by virtue of the tight intramolecular ion pairing. More active zwitterionic catalysts can be generated through reaction of B(C₆F₅)₃ with suitable organozirconium pre-catalysts. The solution and solid state structures of several of these compounds are discussed, highlighting the various mechanisms of stabilization found in the catalyst structures. This revised version was published online in June 2006 with corrections to the Cover Date.