Dynamic Interfacial Properties between a Flexible Isotropic Polymer and a TLCP Investigated by an Ellipsoidal Drop Retraction Method

R. Yu, W. Yu, C. Zhou and J. J. Feng

J. App. Polym. Sci. 94, 1404-1410 (2004)

Abstract - In this study, the dynamic interfacial properties between an isotropic polymer and a thermotropic liquid crystalline polymer (TLCP) are investigated by measuring the time dependent interfacial tension between them. The interfacial tension between TLCP and polymer in the melted state is measured by ellipsoidal drop retraction process of a TLCP drop in flexible polymer matrix. The ellipsoidal model of Maffettone and Minale, the model of Marrucci and Santo, and large deformation ellipsoidal model by Jackson-Tucker and Yu-Bousmina are utilized to calculate the interfacial tension. It is found that the retraction process of a TLCP ellipsoidal drop cannot be described by these models as well as in the Newtonian systems. The apparent interfacial tension obtained from these models evolves with time, which is ascribed to the slow relaxation mechanism in TLCP drop.