Shear flow induced transition from liquid-crystalline to polymer behavior in side-chain liquid crystal polymers

Laurence Noirez (1) , A. Lapp (1)

1 LLB - UMR 12 - Laboratoire Léon Brillouin

We determine the structure and conformation of side-chain liquid-crystalline polymers subjected to shear flow in the vicinity of the smectic phase by neutron scattering on the velocity gradient plane. Below the nematic-smectic transition we observe a typical liquid-crystal behavior; the smectic layers slide, leading to a main-chain elongation parallel to the velocity direction. In contrast, a shear applied above the transition induces a tilted main-chain conformation which is typical for polymer behavior.

Domaines: Matière Molle [cond-mat.soft]

Laurence Noirez, A. Lapp. Shear flow induced transition from liquid-crystalline to polymer behavior in side-chain liquid crystal polymers. Physical Review Letters, 1997, 78 (1), pp.70-73. ⟨10.1103/PhysRevLett.78.70⟩. ⟨hal-01361942⟩