초록 |
Recently, the melt-blending of thermotropic liquid crystalline polymers (TLCPs) with thermoplastics has attracted great attention because of the improvement in the strength and modulus of polymer composites. TLCPs exhibited a relatively low melt viscosity, and could be oriented to form fibrils under elongational flow during the melt processing. The fibrillation of TLCP in the melt blends has been influenced by various factors such as thermal behavior of the component polymers and their compatibility, composition ratio of blends, viscosity of the component polymers and their viscosity ratio, processing temperature, and shear rate. TLCP/PEN and TLCP/PET binary blends were prepared by melt blending in Haake Rheometer equipped with twin screw, in order to investigate effect of viscosity ratio and viscosities of the component polymers on the properties of binary blend systems. The predetermined compositions of binary blends were 5/95, 90/10, and 85/15 in weight ratio, respectively. The properties of TLCP/PEN and TLCP/PET binary blends were analyzed by DSC, SEM, tensile testing, capillary rheometer, and image analysis. When the viscosity ratio of binary blends was close to unity, the size of dispersed TLCP was smaller, and low viscosity ratio could favoured the fibrillation in binary blend systems. |