Molecular mobility in comb-like copolymethacrylates with chalcone-containing side-chains
| Autor: | Alexander V. Yakimansky, Ricardo Díaz-Calleja, N. A. Nikonorova |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Chalcone
Chromophore group Materials science Molar fractions Polymers and Plastics Polymers Local motions Nonlinear optical chromophore Polymer films Dielectric relaxation Ester groups Methacrylate Mole fraction Molecular mobility Second-order nonlinear optical chemistry.chemical_compound Chalcones Non-centrosymmetric Glassy state Comb-like copolymethacrylates Polymer chemistry Chromophore group mobility Materials Chemistry Side chain Segmental mobility Nonlinear optical chromophores chemistry.chemical_classification Side-chains Comonomer Organic Chemistry Cooperative motion Polymer Chromophore Chromophores chemistry MAQUINAS Y MOTORES TERMICOS Co-monomer Comb-like Glass Film preparation Optimal temperature Glass transition Rubbery state |
| Zdroj: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia instname |
| ISSN: | 0959-8103 |
| DOI: | 10.1002/pi.3065 |
| Popis: | [EN] The molecular mobility of comb-like copolymers of amyl methacrylate with N-methacryloyl-(4-amino-4'-bromochalcone) with various concentrations (20, 30, 40, 50 and 60 mol%) of chalcone-containing comonomer was studied using dielectric spectroscopy. It was found that chalcone chromophores participate in two forms of molecular mobility: cooperative motion in the rubbery state (delta-relaxation) and local motion in the glassy state (beta-relaxation). In addition, alpha-, beta(1)- and gamma-processes, being related to cooperative segmental mobility, to local motion of ester groups adjacent to the backbone and to local motion of terminal side-groups, respectively, were evident. The molecular mobility of the beta(1)-, beta-and gamma-processes changed slightly with the concentration of chromophore groups. For the delta- and alpha-processes, the glass transition temperatures, T(delta) and T(g), increased with the molar fraction of chalcone groups, the difference between them remaining nearly constant (ca 55 degrees C). The Td values obtained should be considered as optimal temperatures for the corona-poling of the chromophore-containing polymers for the preparation of second-order nonlinear optical polymer films with non-centrosymmetric arrangement of chromophore groups. (C) 2011 Society of Chemical Industry This research was supported by a grant of the Polytechnic University of Valencia (resolution of UPV from 13.05.08) and a grant of CICYT (MAt2008-06725-C03-03). |
| Databáze: | OpenAIRE |
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