Gas permeability of carborane-containing polyamides

The gas permeation properties of two novel polyamides comprising m-carborane groups in the backbone have been first studied. The polymers have been synthesized by the polycondensation of m-carboranedicarboxylic acids and two diamines. It has been found that the synthesized polyamides exhibit unexpectedly low glass transition temperatures (140 and 173°C). For a number of light gases, permeability (P) and diffusion (D) coefficients have been measured and solubility coefficients as the S = P/D ratio have been determined. The parameters found have been compared with the P, D, and S values of other aromatic polyamides. It has been shown that according to these transport parameters, the novel polyamides are similar to many of the previously studied aromatic polyamides.