TY - JOUR
T1 - Effect of crosslinker geometry on equilibrium thermal and mechanical properties of nematic elastomers
AU - Clarke, S. M.
AU - Hotta, Atsushi
AU - Tajbakhsh, A. R.
AU - Terentjev, E. M.
PY - 2001/1/1
Y1 - 2001/1/1
N2 - We study three monodomain (single-crystal) nematic elastomer materials, all side-chain siloxane polymers with the same mesogenic groups but with different types of crosslinking: (i) short flexible siloxane linkage affine to the network backbone, (ii) short flexible aliphatic crosslinks miscible with mesogenic side chain groups, and (iii) long segments of main-chain nematic polymer. Equilibrium physical properties of these three systems are very different, especially the spontaneous thermal expansion and anisotropic stress-strain response along and perpendicular to the uniform nematic director. In the latter case, we examine the soft elastic plateau during the director reorientation. We compare the nematic order-parameter [formula presented] provided primarily by the side mesogenic groups and relatively constant between the samples, and the average backbone chain anisotropy [formula presented] which is strongly affected by the crosslinking geometry. The experimental data is compared quantitatively with theoretical models of nematic elastomers.
AB - We study three monodomain (single-crystal) nematic elastomer materials, all side-chain siloxane polymers with the same mesogenic groups but with different types of crosslinking: (i) short flexible siloxane linkage affine to the network backbone, (ii) short flexible aliphatic crosslinks miscible with mesogenic side chain groups, and (iii) long segments of main-chain nematic polymer. Equilibrium physical properties of these three systems are very different, especially the spontaneous thermal expansion and anisotropic stress-strain response along and perpendicular to the uniform nematic director. In the latter case, we examine the soft elastic plateau during the director reorientation. We compare the nematic order-parameter [formula presented] provided primarily by the side mesogenic groups and relatively constant between the samples, and the average backbone chain anisotropy [formula presented] which is strongly affected by the crosslinking geometry. The experimental data is compared quantitatively with theoretical models of nematic elastomers.
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U2 - 10.1103/PhysRevE.64.061702
DO - 10.1103/PhysRevE.64.061702
M3 - Article
AN - SCOPUS:85035257788
VL - 64
JO - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
JF - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
SN - 1063-651X
IS - 6
ER -