Recent Advances in the Theory of Filler Networking in Elastomers
Recent Advances in the Theory of Filler Networking in Elastomers
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DOI：
10.1007/3-540-45362-8_1
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发表时间：
2002
影响因子：
--
通讯作者：
G. Heinrich;M. Klüppel
中科院分区：
文献类型：
--
作者：
G. Heinrich;M. Klüppel
本文综述了炭黑填充弹性体的粘弹性能，重点讨论了复合动态模量的应变依赖性（Payne效应）。在过去已经取得了相当大的进展，在低应变幅下的典型的动态行为，在不同大小的典型集群，包括无限的填料网络的物理填料-填料键的循环故障和再团聚。现象学的聚集/解聚克劳斯方法和最近的半微观网络方法（两个聚集VTG模型，链接节点斑点模型，动力学集群集群聚集）之间的共同特点进行了讨论。所有的半微观模型包含的假设的几何排列的子单元（聚集体），特别是填料网络结构，导致例如从渗滤或动力学簇-簇聚集。这些概念预测了佩恩效应的一些特征，这些特征独立于特定类型的填料。这些特征与实验研究结果吻合较好。例如，储能模量G′的形状指数m随变形的增加而下降，这取决于团簇网络的结构。另一个例子是预测作为填料体积分数的函数的弹性模量的特定幂律行为的比例关系。指数反映了分形填料簇和相应填料网络的特征结构。现有的概念的填料网络的故障和改造似乎是足够的描述填充橡胶的动态力学性能的变形依赖性。不同的方法表明，在一个共同的方式，有一个变化的填料结构，增加动态应变。然而，在所有情况下，附加的假设是关于伴随的能量耗散过程，赋予更高的滞后填充橡胶。这个过程可能是纠缠的滑动在结合橡胶层和移动的橡胶相之间的过渡层中，和/填充弹性体的理论理解已经提高到这样的程度，现在可以在较大长度尺度上的填料结构和聚合物的粘弹性之间建立联系。橡胶材料。
The viscoelastic properties of (mostly carbon black) filled elastomers are reviewed with emphasis on the strain-dependence of the complex dynamic modulus (Payne effect). Considerable progress has been made in the past in relating the typical dynamical behavior at low strain amplitudes to a cyclic breakdown and reagglomeration of physical filler-filler bonds in typical clusters of varying size, including the infinite filler network. Common features between the phenomenological agglomeration/deagglomeration Kraus approach and very recent semi-microscopical networking approaches (two aggregate VTG model, links-nodes-blobs model, kinetical cluster-cluster aggregation) are discussed. All semi-microscopical models contain the assumption of geometrical arrangements of sub-units (aggregates) in particular filler network structures, resulting for example from percolation or kinetical cluster-cluster aggregation. These concepts predict some features of the Payne effect that are independent of the specific types of filler. These features are in good agreement with experimental studies. For example, the shape exponentmof the storage modulus, G′, drop with increasing deformation is determined by the structure of the cluster network. Another example is a scaling relation predicting a specific power law behavior of the elastic modulus as a function of the filler volume fraction. The exponent reflects the characteristic structure of the fractal filler clusters and of the corresponding filler network. The existing concepts of the filler network breakdown and reformation appear to be adequate in describing the deformation-dependence of dynamic mechanical properties of filled rubbers. The different approaches suggest in a common manner that there is a change of filler structure with increasing dynamic strain. However, in all cases additional assumptions are made about the accompanying energy dissipation process, imparting higher hysteresis to the filled rubber. This process may be slippage of entanglements (slip-links) in the transition layer between bound rubber layer and mobile rubber phase, and/or partially release of elastically ‘dead’ immobilized rubber trapped within the filler network or agglomerates.The theoretical understanding of filled elastomers has been improved to the extent that now a connection can be made between the filler structures on larger length scales and the viscoelastic properties of rubbery materials.