Water-Transport Properties in Polyetherimide Blends with a Liquid Crystal Polymer

摘要

The effect of the addition of a liquid crystal polymer (Rodrun) on the sorption and transport properties of water through films of a polyetherimide (PEI, Ultem 1000) was investigated. A Cahn electrobalance was empolyed for measuring the water uptatk by the polymer samples. Sorption measurements were made with films of PEI, Rodrun, and heterogeneous PEI-Rodrun blends at different water activities at 30 deg C. In all cases, diffusion ans sorption coefficients when the amount of Rodrun increased. Values of water-sorption isotherms were adjusted to different models. Permeabilities for the different samples were indirectly obtained using experimental values of the solubility and diffusion coefficients described above. Furthermore, permeabilities of the binary composite material were calculated on the basis of those of the pure components and some theoretical assumptions concerning blend morphology. Results were consistent with a Rodrun structure in the composite intermediate between a fibrillar and a laminar morpholigy.