Effects of Surface Conditions on Rheological Properties and Phase Orientation of Sheared LCP Melts in Nanochannels by MD Studies

Abstract:

The rheological properties and phase orientation of liquid crystalline polymer (LCP) melts flowing in a nanochannel with different surface roughness are investigated by molecular dynamics (MD) simulations. Simulation results show the surface roughness has great impact on the rheological properties and phase orientation of LCP melts in the nanochannel (cross section is 12nm). As the amplitude of serrations increases, the shear viscosity increases nonlinearly and the value of orientational order parameter decreases. When the serration amplitude is larger than 1.1nm, a phase transition (from nematic to isotropic phase) of LCP melt happens, which makes flowing in nanochannels more difficult. On the other hand, the influence of serration period on the shear viscosity and orientational order parameter are found not so obvious. Findings in this study will be helpful for injection molding plastic products with nanofeatures.

• Periodical: Materials Science Forum (Volumes 532-533)
• Pages: 624-627
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.532-533.624
• Online since: December 2006
• Authors: Lan He, Kai Leung Yung, Yun Wen Shen, Yan Xu
• Keywords: GB-Spring-Bead Model, Liquid Crystal Polymer (LCP), Molecular Dynamic Simulation, Shear Viscosity, The Orientational Order Parameter

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