Mechanical Modeling of the Strain‐Induced‐Crystallization in Polymers
Mechanical Modeling of the Strain‐Induced‐Crystallization in Polymers
复制标题
聚合物应变诱导结晶的机械建模
DOI：
10.1002/pamm.201710164
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Klinge
中科院分区：
文献类型：
--
作者：
Aygün;Klinge
应变诱导结晶(SIC)是一种由高变形或温度降低引起的天然增强现象。这是天然橡胶的典型特征，因为这种材料比其他聚合物含有更多规则取向的链。大多数关注聚合物模型的模型都以自由能的朗之万式为基础[1]。然而，目前的工作将受应变诱导结晶影响的聚合物视为由具有不同程度网络规则性的区域组成的非均质介质。这一概念允许描述晶区的成核和生长以及有效材料参数的变化，这取决于所施加的应变水平。提出的模型在热力学上是一致的。它是基于对自由亥姆霍兹能量和耗散势的假设。非弹性变形和网络规整化程度是内变量。根据耗散势的最小原理，导出了它们的演化方程。(2017Wiley-VCH Verlag GmbH&Co.KGaA，Weinheim)
The strain‐induced crystallization (SIC) in polymers is a phenomenon manifesting itself as the natural reinforcement caused by the high deformation or by the reduction of the temperature. It is typical for natural rubber, since this material contains more regularly oriented chains than the other polymers. Most of the models focusing on the modeling of polymers use the Langevin expression for the free energy as a basis [1]. The current work, however, treats a polymer affected by the strain induced crystallization as a heterogeneous medium consisting of regions with a different degree of network regularity. Such a concept allows the depiction of the nucleation and the growth of crystalline regions as well as the change of effective material parameters depending on the level of the strain applied. The model proposed is thermodynamically consistent. It is based on the assumptions for the free Helmholtz energy and dissipation potential. The inelastic deformations and degree of the network regularity are internal variables. Their evolution equations are derived according to the minimum principle of the dissipation potential. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)