Transient Behavior of Liquid Crystalline Solutions of Poly(benzylglutamate)
Transient Behavior of Liquid Crystalline Solutions of Poly(benzylglutamate)
复制标题
聚谷氨酸苄酯液晶溶液的瞬态行为
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
J. Mewis
中科院分区：
文献类型：
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作者：
P. Moldenaers;J. Mewis
研究了聚-γ-苄基-L-谷氨酸盐（PBLG）在间甲酚中的溶液。在稳态剪切流和振荡流的粘弹性特性。证实了稳定的负第一法向应力差的存在。动态牛顿粘度比相应的稳态剪切值小得多。利用动态测量详细研究了停止流动后的瞬态行为。流动停止后，动态模量在一个时间尺度上的变化是远远大于应力松弛。分析了频率、温度和前剪切速率的影响。对数据的结构解释进行了讨论。聚合物液晶的可用模型必须进一步开发之前，与目前的结果进行比较成为可能。
A solution of poly‐γ‐benzyl‐L‐glutamate (PBLG) in m‐cresol has been investigated. Viscoelastic properties during steady state shear flow and in oscillatory flow are presented. The existence of a stable negative first normal stress difference is confirmed. The dynamic Newtonian viscosity is considerably smaller than the corresponding steady state shear value. The transient behavior after cessation of flow is studied in detail using dynamic measurements. After cessation of flow, the dynamic moduli change over a time scale which is much larger than that for stress relaxation. Effects of frequency, temperature and previous shear rate are analyzed. The structural interpretation of the data is discussed. Available models for polymeric liquid crystals have to be developed further before a comparison with the present results becomes possible.