Structure and dynamics of polymer rings by neutron scattering: breakdown of the Rouse model
Structure and dynamics of polymer rings by neutron scattering: breakdown of the Rouse model
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DOI：
10.1039/c1sm06257c
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发表时间：
2011-01-01
期刊：
影响因子：
3.4
通讯作者：
Richter, Dieter
中科院分区：
文献类型：
--
作者：
Bras, Ana R.;Pasquino, Rossana;Richter, Dieter
我们提出了一个静态和准弹性中子散射研究的结构和动力学的环状聚合物在一个环和线性聚合物熔体，分别。在第一种情况下，与具有相同分子量的直链相比，环结构被证明是显著更紧凑的。小角中子散射（SANS）证实，在混合物中，环分子膨胀，根据理论和模拟工作。这两个系统的动力学行为，这是第一次已经探索了中子自旋回波光谱（NSE），显示出令人惊讶的快速中心的质量扩散相比，线性聚合物。这些结果同意定性与原子分子动力学模拟。快速扩散被证明是对劳斯模型的明显违反。
We present a static and quasi-elastic neutron scattering study on both the structure and dynamics of a ring polymer in a ring and linear polymer melt, respectively. In the first case, the ring structure proved to be significantly more compact compared to the linear chain with the same molecular weight. In the mixture, the ring molecules swell as was confirmed by small angle neutron scattering ( SANS) in accordance with both theory and simulation work. The dynamical behavior of both systems, which for the first time has been explored by neutron spin echo spectroscopy (NSE), shows a surprisingly fast center of mass diffusion as compared to the linear polymer. These results agree qualitatively with the presented atomistic MD simulations. The fast diffusion turned out to be an explicit violation of the Rouse model.