Anisotropic orientational behaviour of liquid crystalline polymer

Abstract

For describing anisotropic behaviour of the material, thermotropic and lyotropic liquid crystalline polymers were investigated by polariscope to take microstructural photos. Experimental investigation on the rheological and rheo-optical behaviour of the HPC was reported. The HPC was used in a extrusion test, a small contraction, nearly planar extrudate and resonance instability due to shear disturbance were observed when the lyotropic LC polymer HPC solution was extruded. A simple stability theory of orientational motion of director vector was developed for the LC polymer fluid that extended flow of thermotropic LC polymer melts is very effective in producing a high degree of macroscopic orientation.

Keywords

liquid crystalline polymer / microstructural state of LC polymer / contraction of extrudate of HPC solution / extrusion-extensional flow / orientational stability theory

References

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