Linear Viscoelastic Behavior of an Azobenzene Nematic Block Copolymer

被引：4
作者：
Andreozzi, Laura [1 ,2 ]
Autiero, Ciro [1 ,2 ]
Faetti, Massimo [1 ,2 ]
Giordano, Marco [1 ,2 ]
Zulli, Fabio [1 ,2 ]
Galli, Giancarlo [3 ,4 ]
Menghetti, Sara [3 ,4 ]
机构：
[1] Univ Pisa, Dipartimento Fis E Fermi, Pisa, Italy
[2] PolyLab IPCF CNR, Pisa, Italy
[3] Univ Pisa, Dipartimento Chim & Chim Ind, Pisa, Italy
[4] INSTM, Pisa, Italy
来源：
MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 2011年 / 549卷
关键词：
azobenzene; block copolymer; liquid crystal; rheology; shear viscosity; RHEOLOGICAL BEHAVIOR; DYNAMICS; HETEROGENEITIES; FRAGILITY; POLYMERS; PROBE;
D O I：
10.1080/15421406.2011.581524
中图分类号：
O6 [化学];
学科分类号：
0703 ;
摘要：
We report on the rheological investigation of a nematic block copolymer of an azobenzene methacrylate (MA4) and methyl methacrylate (MMA). Relaxation processes are discussed in terms of chain architecture and viscoelastic response of the polymer. In contrast to analogous random copolymers of MMA and MA4, the present block copolymer did not show validity of the time-temperature superposition (TTS) principle for all material functions. TTS was found to work only for the storage modulus. Rheological steady-state and oscillatory measurements were thus compared in order to obtain further insight into such a peculiar phenomenon.
引用
收藏
页码：133 / 139
页数：7
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