Chain retraction potential in a fixed entanglement network.
Chain retraction potential in a fixed entanglement network.
复制标题
固定纠缠网络中的链收缩潜力。
DOI：
10.1103/physrevlett.94.076001
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发表时间：
2005
影响因子：
8.6
通讯作者：
R. Larson
中科院分区：
文献类型：
--
作者：
S. Shanbhag;R. Larson
当一端系着的链条浸入固定的缠结网络时，链条的移动端会遇到熵势势垒，这种势垒会抑制使链条末端接近系结点所需的深度波动。Doi和Kuzuu [J]。变异较大。科学。,变异较大。列托人。Ed. 18, 775(1980)]估计这种势对于描述支化聚合物在固定网络和熔体中的流变性至关重要，它具有前因子nu = 1.5的二次形式。后来基于规则格的计算表明势是非二次型的，其陡度取决于格配位数。在这篇论文中，我们分析了用键波动模型得到的具有高达12.5个缠结的链的原始路径。我们的模拟证实了势能的二次型，其前因子接近于Doi-Kuzuu值，nu约为1.5。
When a chain, tethered at one end, is immersed in a fixed entanglement network, the mobile tip of the chain encounters an entropic potential barrier that penalizes deep fluctuations needed to bring the tip close to the tethering point. Using the tube model, Doi and Kuzuu [J. Polym. Sci., Polym. Lett. Ed. 18, 775 (1980)] estimated that this potential, which is crucial to describe the rheology of branched polymers in fixed networks and melts, has a quadratic form with a prefactor nu = 1.5. Later calculations based on regular lattices indicated that the potential is nonquadratic, and its steepness depends on the lattice coordination number. In this Letter, we analyze the primitive paths obtained using the bond-fluctuation model for chains with up to 12.5 entanglements. Our simulations confirm a quadratic form for the potential with a prefactor close to the Doi-Kuzuu value, nu approximately 1.5.