Structural relaxation of polymers at the glass transition: conformational memory in poly(n-alkylmethacrylates).
Structural relaxation of polymers at the glass transition: conformational memory in poly(n-alkylmethacrylates).
复制标题
聚合物在玻璃化转变时的结构松弛：聚（甲基丙烯酸正烷基酯）中的构象记忆。
DOI：
10.1103/physrevlett.91.155702
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发表时间：
2003
影响因子：
8.6
通讯作者：
H. Spiess
中科院分区：
文献类型：
--
作者：
M. Wind;R. Graf;A. Heuer;H. Spiess
构象记忆作为聚合物结构松弛的一个新方面被引入。在聚甲基丙烯酸正烷基酯中，通过先进的核磁共振技术将延伸的主链构象识别为参与结构松弛的分子单元。它们在限制轴向链运动的许多步骤中保留了构象记忆。构象的随机化和主链方向的各向同性发生在相同的时间尺度上，但比迄今为止发现的最慢的弛豫过程要慢得多。在这种新的链松弛过程中发现了易碎玻璃形成体的典型行为。
Conformational memory is introduced as a new aspect of structural relaxation of polymers. In poly(n-alkylmethacrylates) extended backbone chain conformations are identified by advanced NMR techniques as the molecular units involved in structural relaxation. They retain conformational memory over many steps of restricted axial chain motion. Randomization of conformation and isotropization of backbone orientation occur on the same time scale, yet much slower than the slowest relaxation process identified so far. Behavior typical of fragile glass formers is found for this new process of chain relaxation.