화학공학소재연구정보센터
Journal of Rheology, Vol.40, No.6, 1233-1237, 1996
Residual Normal Force After Cessation of Squeezing Flow of Liquid-Crystalline Polymers
Classical Liquid crystal theories are used to develop a model to compute the normal forces and shear torques for liquid crystalline polymers. The model is applied to the parallel disk geometry and the normal forces from three representative average molecular orientations are computed. It is found that a positive normal force lending to separate the parallel disks will always be present whenever the orientation is subjected to a twisting deformation. For typical parameter values and geometries, the model predicts that normal forces are six orders of magnitude larger than shear torques. The model predictions are validated with the experimental data presented by Langelaan and Gotsis (1996).