A theoretical and experimental study of filler effect on stress-deformation-segmental orientation relations for poly(dimethylsiloxane) networks
A theoretical and experimental study of filler effect on stress-deformation-segmental orientation relations for poly(dimethylsiloxane) networks
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DOI：
10.1021/ma000261t
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发表时间：
2000-11-14
期刊：
影响因子：
5.5
通讯作者：
Erman, B
中科院分区：
文献类型：
--
作者：
Bokobza, L;Erman, B
二氧化硅填充的聚（二甲基硅氧烷）网络的应力-应变，红外二向色性，和双折射实验的结果表明，随着变形的增加，而段取向应变关系保持线性在相同的变形范围内的应力强烈上升。由于这种差异，应力光学系数表现出不寻常的依赖于变形。从Mooney-Rivlin曲线的上升可以推断，应力的上升是由于链的有限延展性造成的。为了从分子的角度解释这些观察结果，我们的特点是不同长度的聚（二甲基硅氧烷）链的端到端分布的Monte Carlo异构态计算和导出的应力-变形-取向关系，这些链的网络，采用三链网络模型。分子模型的结果，在平行的实验观察，应力和取向行为之间表现出强烈的差异。
Results of stress-strain, infrared dichroism, and birefringence experiments on silica-filled poly(dimethylsiloxane) networks show strong upturns of the stress with increasing deformation while segmental-orientation-strain relations remain linear over the same deformation range. As a result of this difference, the stress-optical coefficient exhibits an unusual dependence on deformation. The upturn in the stress results from the limited extensibility of the chains, inferred from the upturns in the Mooney-Rivlin plots presented. To explain these observations from a molecular perspective, we characterized the end-to-end distributions of different length poly(dimethylsiloxane) chains by Monte Carlo isomeric state calculations and derived stress-deformation-orientation relations for networks made of these chains by employing the three-chain network model. The results of the molecular model, in parallel with experimental observation, show strong differences between stress and orientation behavior.