F. Diaz Camacho  R. Le Lagadec  Alexander D. Ryabov  L. Alexandrova 《Journal of polymer science. Part A, Polymer chemistry》2008,46(12):4193-4204

The cyclometalated complex [Ru^II(o‐C₆H₄‐py)(MeCN)₄]PF₆ ( 1 ) with a σ‐Ru? C bond and four substitutionally labile acetonitrile ligands mediates radical polymerization of different vinyl monomers, viz. n‐butyl acrylate, methyl methacrylate, and styrene, initiated by three alkyl bromides: ethyl 2‐bromoisobutyrate, methyl 2‐bromopropionate, and 1‐phenylethyl bromide. The polymerization requires the presence of Al(OiPr)₃ and occurs uncontrollably as a conventional radical process. The variation of the molar ratio of the components of the reaction mixture, such as initiator, Al(OiPr)₃ and catalyst, affected the polymerization rates and the molecular weights but did not improve the control. A certain level of control has been achieved by adding 0.5 eq of SnCl₂ as a reducing agent. Tin(II) chloride decreased the rate of polymerization and simultaneously the molecular weights became conversion‐dependent and the polydispersities were also narrowed. Remarkably, the level of control was radically improved in the presence of excess of the poorly soluble catalyst ( 1 ), when the added amount of ( 1 ) was not soluble any more, i.e., under heterogeneous conditions, the system became adjustable and the living polymerization of all three monomers was finally achieved. Possible mechanisms of the ( 1 )‐catalyzed polymerization are discussed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4193–4204, 2008  相似文献   

    

Natalia A. Nikonorova  Nikolai N. Smirnov  Ricardo Diaz‐Calleja  Alexander V. Yakimansky 《Journal of Polymer Science.Polymer Physics》2008,46(14):1488-1496

Local forms of molecular mobility of comb‐like random copolymethacrylates, containing side‐chain nonlinear optical chromophores and amyl‐ or octafluoroamyl‐groups, are studied. In the glassy state, two relaxation processes are found, which are due to reorientation of terminal polar groups (γ₂‐process) and rotation of chromophore groups about their long axes (β‐process). For octafluoroamyl‐containing copolymers, the γ₂‐process is superposition of the two molecular motions due to reorientation of terminal chromophore groups and ? CF₂H groups. The intensity and relaxation times in the range of the γ₂‐process depend on the chemical structure and concentration of chromophores in a copolymer. For the β‐process, the molecular mobility weakly depends on the chromophore structure, being mainly determined by the relative lengths of the rigid chromophore and flexible side chains. On the global spectrum of depolarization current it was observed the γ₁‐process due to reorientation of (CH₂)_n spacers between chromophore groups and copolymer backbone. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1488–1496, 2008  相似文献   

    

Mayoral A  Carey T  Anderson PA  Lubk A  Diaz I 《Angewandte Chemie (International ed. in English)》2011,50(47):11230-11233

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Carlo Lamberti  Carmelo Prestipino  Francesca Bonino  Luciana Capello  Silvia Bordiga  Giuseppe Spoto  Adriano Zecchina  Sofia Diaz Moreno  Barbara Cremaschi  Marco Garilli  Andrea Marsella  Diego Carmello  Sandro Vidotto  Giuseppe Leofanti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2002,114(13):2447-2450

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Mark A. Newton  Andrew J. Dent  Sofia Diaz‐Moreno  Steven G. Fiddy  John Evans 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2002,114(14):2699-2701

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R.G. Rubio  J.A.R. Renuncio  M.Diaz Peña 《Thermochimica Acta》1983,65(1):69-79

The vapor pressures for benzene + n-dodecane mixtures have been measured using a static apparatus. Values for the excess Gibbs energy have been calculated using a modified form of Barker's method and fitted to a Padé approximant equation. Selection of the most adequate approximant is made according to objective criteria. The results are compared with those corresponding to other benzene + n-alkane systems. The values for the activity coefficient of benzene at infinite dilution calculated from these data agrees very well with the values obtained by gas-liquid chromatography.  相似文献   

    

Bingfei Cao  Dr. Gabriel M. Veith  Dr. Rosa E. Diaz  Jue Liu  Dr. Eric A. Stach  Dr. Radoslav R. Adzic  Prof. Peter G. Khalifah 《Angewandte Chemie (International ed. in English)》2013,52(41):10753-10757

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Melvina Leolukman  Peerasak Paoprasert  Ian Mandel  Solimar J. Diaz  David J. Mcgee  Padma Gopalan 《Journal of polymer science. Part A, Polymer chemistry》2009,47(19):5017-5026

Linear‐dendritic block copolymer hosts were synthesized by end‐functionalizing poly(methylmethacrylate) with dendrons that acted as hydrogen‐bonding acceptors for nonlinear optical chromophores. Second harmonic generation experiments indicate that the d₃₃ coefficients and maximum chromophore loading are increased in linear‐dendritic block copolymer hosts over comparable homopolymer hosts. Transmission electron microscopy shows 5–10 nm chromophore domains, confirming the effective spatial dispersion of the chromophores. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5017–5026, 2009  相似文献   

    

Francisco Diaz Camacho  Salvador Lopez Morales  Ronan Le Lagadec  Larissa Alexandrova 《Macromolecular Symposia》2006,242(1):25-33

Polymerizations of n-butyl acrylate (BA), methyl methacrylate (MMA) and styrene (St) were promoted by the Ru(II) cyclometalated complex with labile MeCN ligand in the presence of Al(OiPr)₃. The polymerization proceeds via radical mechanism and requires the loss of MeCN ligand. The poor control over the polymerizations can be explained in terms of the traditional ATRP scheme. However, the controllability may be significantly improved by addition of reducing SnCl₂. Mechanism of the process is proposed.  相似文献   

Development and validation of an HPLC method for determination of amphotericin B in plasma and sputum involving solid phase extraction     

M. A. Campanero  A. M. Zamarreño  M. Diaz  M. C. Dios-Vieitez  J. R. Azanza 《Chromatographia》1997,46(11-12):641-646

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