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首页> 外文期刊>Journal of Applied Polymer Science >Molecular dynamics in semifluorinated-side-chain polysulfone studied by broadband dielectric spectroscopy
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Molecular dynamics in semifluorinated-side-chain polysulfone studied by broadband dielectric spectroscopy

机译：宽带介电谱研究半氟化侧链聚砜的分子动力学

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摘要

The molecular dynamics of a set of polysulfone polymers have been studied with broadband dielectric spectroscopy. The materials comprise main-chain polysulfones attached to semifluorinated (SF) oxydecylperfluorodecyl side chains. Through the analysis of the dielectric data together with information from differential scanning calorimetry and small-angle X-ray scattering, it can be shown that the oxydecylperfluorodecyl side chains are microphase-separated and form nanodomains with an independent dynamic glass-transition (delta(SF)) relaxation. In addition to the a process (which is the glass transition of the main chain), other relaxation processes can be detected with Arrhenius-type activation energies of 38-90 +/- 2 kJ/mol. A gamma(SF) process, observed only in polysulfone with SF side chains, can be assigned to librational fluctuations of the perpendicular component of the fluoroalkyl group. A gamma beta relaxation reflects fluctuations of the dipole moments (O=S=O and C=O) of the polymer, whereas a process, with high activation energies (>70 +/- 2 kJ/mol), is assigned to packaging defects in the material. A detailed description of the processes is provided together with a proposed relaxation scheme. (C) 2007 Wiley Periodicals, Inc.
机译：用宽带介电谱研究了一组聚砜聚合物的分子动力学。该材料包括连接至半氟化（SF）氧癸基全氟癸基侧链的主链聚砜。通过对介电数据以及差示扫描量热法和小角度X射线散射的信息进行分析，可以证明氧癸基全氟癸基侧链是微相分离的，并形成具有独立动态玻璃化转变（delta（SF ）） 松弛。除了a过程（这是主链的玻璃化转变）以外，还可以使用38-90 +/- 2 kJ / mol的阿伦尼乌斯型活化能检测到其他弛豫过程。仅在带有SF侧链的聚砜中观察到的γ（SF）过程可以归因于氟代烷基垂直成分的自由波动。 γβ弛豫反映了聚合物的偶极矩（O = S = O和C = O）的波动，而具有高活化能（> 70 +/- 2 kJ / mol）的过程被指定为包装缺陷在材料上。提供了过程的详细说明以及建议的松弛方案。 （C）2007 Wiley期刊公司

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