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Novel cross‐linked polyphosphazenes with remendable capacity have been synthesized through the Diels‐Alder reactions. Their structure and properties were characterized by NMR, FT‐IR, GPC, DSC, TGA SEM, and polarizing microscope. The process of Diels‐Alder reaction (D‐A reaction) and retro‐Diels‐Alder reaction (retro‐D‐A reaction) have been investigated by FT‐IR, UV, and DSC. The cross‐linked polyphosphazenes exhibited remendable capability only need a thermal treatment when they were cut by blade, any other treatments such as additional monomer or catalyst, surface treatment or pressure were not needed. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   
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Detection and the simultaneous removal of mercury ions are of vital importance. In this study, fluorescent monomers, small molecular sensors, were first synthesized using 4‐bromo‐naphthalic anhydride as precursor. These double bond bearing sensors were then grafted to polystyrene (PS) microspheres through dispersion polymerization. The sensors still retained their detecting ability when they were anchored on the surfaces of PS microspheres. Upon the addition of Hg2+ ions to the PS microspheres, both the color and the fluorescence intensity changed, which could be employed to detect Hg2+ ions. The absorption capacity of the two kinds of PS microspheres reached 0.557 mg g?1 and 0.628 mg g?1 respectively. The PS microspheres still remain their fluorescence and absorption even used for five times. These polymeric highly sensitive chemosensors may see their applications in purification of polluted environments. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4592–4600  相似文献   
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It has been a challenge to synthesize high molecular weight and soluble conjugated hyperbranched poly(1,2,3‐triazole)s (hb‐PTAs). In this paper a series of soluble hyperbranched polytriazoles, whose number‐average molecular weight (Mn) and polydispersity index ranged in (1.2–3.3)×104 and 1.7–3.0, respectively, were synthesized with A2+B3 approach. In the polymerization process, diazides A1 – A4 and triyne B1 were used as A2 and B3 monomers; Cu(I)‐catalyst, THF and water were used as their reaction system. At room temperature the final molecular weight could be controlled through reaction time, so finally we obtained soluble conjugated hyperbranched poly(1,2,3‐triazole)s hb‐PTAs (1–4 ). The polymers were soluble in common organic solvents, and all emitted blue light; the films of polymers emitted yellow and blue light, due to the difference in the aggregation of their chromophoric units in the solid state. The thermal properties of the final copolymers were analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).  相似文献   
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以二甲基二氯硅烷和乙醇气嘧《相醇解反应制得单乙氧基二甲基氯硅烷,然后加入催化剂FeCl3回流反应制得中间体二氯四甲基二硅氧烷,进一步在无水乙醚中用CaH2还原中间体得到1,1,3,3-四甲基二硅氧烷,产率高达86%.同时对影响产率的因素进行了系统探讨,并通过元素分析、红外光谱、核磁共振氢谱确认了1,1,3,3-四甲基二硅氧烷的结构.与其他方法相比,该法原料易得,操作简便,价格低廉,易实现工业化.  相似文献   
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本文研究了介质对交流粉末电致发光器件的发光老化性的影响,用具有特殊性能的水溶性苯丙乳胶作为介质制备的交流粉末电致发光器件,其发光老化性能理到较大幅度提高;并分析了这种发光器件老化的主要原理和机制,提出防止发光老化应注意的问题。  相似文献   
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Chiral aminosulfonamides containing imidazolium group were used as ligands for the ruthenium(II)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in ionic liquid, affording good to excellent conversions and enantiomeric excesses. The catalytic system could be easily recovered and reused several times.   相似文献   
39.
A chemo‐sensor [Ru(bpy)2(bpy‐DPF)](PF6)2 ( 1 ) (bpy=2,2′‐bipyridine, bpy‐DPF=2,2′‐bipyridyl‐4,4′‐bis(N,N‐di(2‐picolyl))formylamide) for Cu2+ using di(2‐picolyl)amine (DPA) as the recognition group and a ruthenium(II) complex as the reporting group was synthesized and characterized successfully. It demonstrates a high selectivity and efficient signaling behavior only for Cu2+ with obvious red‐shifted MLCT (metal‐to‐ligand charge transfer transitions) absorptions and dramatic fluorescence quenching compared with Zn2+ and other metal ions.  相似文献   
40.
金属离子Bi(Ⅲ)络合物体系的极谱法研究   总被引:1,自引:0,他引:1  
在络合剂与金属离子浓度比固定条件下 ,改变溶液的pH值 ,用示差脉冲极谱技术研究金属离子Bi(Ⅲ ) 邻吡啶甲酸络合物体系 .根据实验得到的极谱峰电流和峰电位随溶液pH的变化 ,设计合适的金属络合物体系模型 .极谱实验络合物形成曲线 (ECFC)和理论络合物形成曲线 (TCFC)被用来检验金属络合物体系模型和优化络合物稳定常数 .含有极谱实验参数 (峰电位的移动和峰电流的变化 )的实验络合物形成曲线是特定金属络合物体系的特征函数 .理论络合物形成曲线的计算是基于金属络合物体系的质量平衡方程 .通过求解体系的质量平衡方程及拟合实验络合物形成曲线 ,用计算机分析程序CFC II优化得到金属络合物的稳定常数及金属离子的各种形态分布图 .计算机分析结果表明 ,在所研究的pH范围内 ,溶液中存在五种金属络合物 :MHL、ML、ML2 、ML3、ML3(OH) ,其稳定常数 (log β)分别为 7.5 2± 0 .15、7.48± 0 .0 6、13 .94± 0 .0 2、18.12± 0 .0 3、2 6.78± 0 .0 3 .  相似文献   
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