MECHANICAL BEHAVIOR OF IN-SITU COMPOSITE POLYMERS

Abstract Tensile and bending properties of blends of two thermotropic liquid crystalline polymers with a polycaroonate and a polyethersulfone have beer. investigated,respectively.The injection molded test bars of these blends exhibite great stiffness due to in-situ formed. fibers of the disperse TLCP phase in matrix duriIg the melt blending and mold filling,ar.d the moduli of the TLCP fibers in the matrix which in the experiment were obtained are substantially higher than those presently known from polymer literature. The processing conditions such as melt temperature and injection speed have a striking influence upon the mechanical properties.Because of immiscibility between TLCP's and matrix polymers,measured by FTIR,there is only weak adhesion between these components,so that the strengths of the blends was found to be similar to that of the unblended matrixes,and a reinforcement was not always observed.The injection molded bars show also great hardness in the cross section,but there is a non-uniform distribution.