Modeling of butyric acid recognition by molecular imprinted polyimide.

The constitutional repeating unit structures of poly(pyromellitic dianhydride-co-4,4'-oxydianiline) or polyamiс acid, butyric acid and complexes between butyric acid and one, two or three units of polyamiс acid were calculated using the density functional theory method (DFT B3LYP) on a 6-31G(d,p) basis with the basis set superposition error (BSSE) correction in the program Gaussian 09. The optimised structures of the template and polyamiс acid allowed to establish intermolecular non-covalent interactions during imprinting and, based on the results, develop a method of polyimide-based molecularly imprinted polymer preparation using butyric acid as template. It was shown that the optimum molar ratio of reagents used for the synthesis of molecularly imprinted polymer is 1:1 (interaction energy ∆E = 43.