Compatibilization of poly(ether imide)/Rodrun blends by means of a polyarylate

A compatibilization method for improving the mechanical properties of thermoplastic/liquid-crystalline polymer (LCP) blends has been tested in blends of poly(ether imide), PEI, with a thermotropic copolyester (Rodrun). It is based on the addition to the blend of a third component, both miscible with the matrix and also able to interact with the LCP. Given the miscibility of a polyarylate (PAr) with PEI up to 20% PAr content, and its probable interactions with Rodrun, a constant 20% PAr was added to the PEI matrix to test its possible compatibilizer activity in PEI/Rodrun blends. The observed decrease in the interfacial tension between the matrix and the dispersed phase induced by the PAr gave rise to a smaller size and to fibrillation of the dispersed phase. Fibrillation also gave rise to improved modulus of elasticity and tensile strength, thus proving the compatibilization activity of PAr. (C) 2000 Elsevier Science Ltd. All rights reserved.