Viscoelastic and Dielectric Relaxation of Reptating Type-A Chains Affected by Reversible Head-to-Head Association and Dissociation
Viscoelastic and Dielectric Relaxation of Reptating Type-A Chains Affected by Reversible Head-to-Head Association and Dissociation
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DOI：
10.1021/acs.macromol.8b00691
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发表时间：
2018-08
期刊：
影响因子：
5.5
通讯作者：
H. Watanabe;Yumi Matsumiya;Y. Kwon
中科院分区：
文献类型：
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作者：
H. Watanabe;Yumi Matsumiya;Y. Kwon
对于发生头对头缔合和解离反应的A型偶极子纠缠线型聚合物，基于重复动力学结合反应动力学，对其粘弹性和介电行为进行了理论分析。具体来说，对于解离的一元聚体和相关的二聚体（分别以j = 1和2为索引），通过取向各向异性和取向记忆的特征函数展开解析计算了归一化复模量gj*(ω)和归一化复介电常数ej*(ω)，取向记忆由纠缠段的键向量u定义。该反应激活了一元和二聚体之间的相互构象转移。由于这种转移，一元和二聚体的各向异性衰减模式发生多重耦合，一元和二聚体的粘弹性g1*和g2*与纯重复情况相比，分别表现出明显的延迟和加速弛豫。相比之下，记忆衰退不…
For entangled linear polymer having type A dipoles and undergoing head-to-head association and dissociation reaction, viscoelastic and dielectric behavior is theoretically analyzed on the basis of the reptation dynamics combined with the reaction kinetics. Specifically, for the dissociated unimer and associated dimer (indexed with j = 1 and 2, respectively), the normalized complex modulus gj*(ω) and the normalized complex dielectric permittivity ej*(ω) are analytically calculated via eigenfunction expansion of the orientational anisotropy and orientational memory defined in terms of the bond vectors u of entanglement segments. The reaction activates mutual conformational transfer between the unimer and dimer. Multiple coupling occurs for the anisotropy decay modes of the unimer and dimer due to this transfer, and the viscoelastic g1* and g2* of the unimer and dimer, respectively, exhibit considerably retarded and accelerated relaxation compared to the pure reptation case. In contrast, the memory decay mo...