A new theory of entanglements and dynamics in dense polymer systems
A new theory of entanglements and dynamics in dense polymer systems
复制标题
致密聚合物体系中纠缠和动力学的新理论
DOI：
10.1021/ma00187a037
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发表时间：
1988
期刊：
影响因子：
5.5
通讯作者：
J. Noolandi
中科院分区：
文献类型：
--
作者：
T. A. Kavassalis;J. Noolandi
纠缠的概念，这是中央的爬行理论，已被重新制定。由de Gennes和Doi和Edwards引入的唯象参数2Ve已被一个新的参数N所取代，称为配位数，它可以从熔融或浓溶液中许多链的构象统计中计算出来。有人认为，通过适当选择N，可以根据一个简单的关系将该量与平均纠缠间距联系起来。N，这是一个预先平均的拓扑参数，也提供了一个标准的存在的纠缠和描述的程度的纠缠的链参数和聚合物密度。的平均纠缠间距示出依赖于在该区域的过渡的聚合度。从纠缠到非纠缠的行为，这是几何起源的过渡，遵循这个理论做几个完善的缩放定律熔体和浓溶液。一个广义的劳斯模型（GRM），修改纳入纠缠效应，已被用来与该理论来描述聚合物在纠缠和非纠缠熔体的动力学。在渐近长链极限下恢复了蠕动理论的结果。
The entanglementconcept, which is central to the reptation theory, has been reformulated. The phenomenological parameter, 2Ve, introduced by de Gennes andDoi and Edwards, has been replaced by a new parameter, N, called the coordination number, which can be computed from the conformational statistics of many chains, in a melt or concentrated solution. It is argued that, with the appropriate choice of N, one can relate thisquantity to the mean entanglement spacing according to a simple relation. N, which is a preaveraged topological parameter, also provides a criterion for the presence of entanglements and describes the degree of entanglement in terms of the chain parameters and polymer density. The mean entanglement spacing is shown to depend on the degree of polymerization in the region of the transition. The transition from entangled to unentangled behavior, which is geometrical in origin, follows from this theory as do several well-established scaling laws for melts and concentrated solutions. A generalized Rouse model (GRM), modified to incorporate entanglement effects, has been used with this theoryto describe polymer dynamics in entangled and unentangled melts. The reptation theory results are recovered in the asymptotic long-chain limit.