Phase separation and morphology of polymer-polymer-solvent systems in an electric field.

摘要

Polymer blends with unique anisotropic morphologies have been produced by the application of electric fields, in the range 0.5 to 15 kV/cm, to polymer-polymer-solvent systems during solvent casting. Blends made in electric fields also showed larger minor phase dimensions than those made outside the field. Two blends were studied in detail; these were PEO-PS and PMMA-PS. Other systems that were observed included, PVAc-PS, PVAc-PMMA, POT-B-PS, PVC-PS and PB-PS. In the PB-PS system, no electric field induced morphology changes were found.;The pearl-chain morphology was usually observed in blends containing small phases (typically ;Partial phase diagrams were constructed for the PMMA-PS-toluene system by experimental determination of tie-lines and by theoretical simulation of spinodal curves. Dielectric constants, viscosities and interfacial tensions (using the pendant drop technique) were measured for coexisting phases that were represented by one of the tie-lines. Interfacial tensions were also calculated by using the shapes of deformed drops in electric fields and the theory of Garton and Krasucki (Proc. R. Soc. London A, 280A, 221, 1964). These values were very low (10