ADDITIVE EFFECTS ON THERMOTROPIC LIQUID-CRYSTAL POLYMER ALLOYS .2. EFFECTS OF 3RD COMPONENT OF THERMOTROPIC LIQUID-CRYSTAL POLYMER ON MECHANICAL-PROPERTIES OF VECTRA-A-REINFORCED POLY(BUTYLENE TEREPHTHALATE)

The effects of addition of the 3rd component of thermotropic liquid crystal polymer (TLCP) on the mechanical properties and structure of Vectra A-reinforced poly(butylene terephthalate) (PBT) were studied. The 3rd TLCP was the copolymer based on p-hydroxybenzoate (PHB) and ethylene terephthalate, known as X-7G. PBT, Vectra A, and the third TLCP were blended in the molten state, the extrudate of which was cut and injection-molded. The mechanical properties of the blends were improved by the combination of the two kinds of TLCP. The dynamic viscoelastic analysis indicated that the thermal endurance of the ternary blends were enhanced when Vectra A was used as a major TLCP reinforcement. SEM revealed that both the binary and ternary blends were phase-separated, and the introduction of the 3rd component of TLCP was profitable for TLCP to form finer fibrils at the skin part of the sample. X-Ray diffraction analysis showed that the orientation of Vectra A fibril in the blend was raised by the addition of the 3rd TLCP, resulting in the improvement of the mechanical properties of the ternary blends. The conclusions obtained in this paper agreed with those reported in our previous paper.