Epoxy-Amine Systems with Reactive Guanidine Derivatives

The modification of epoxy-amine systems with reactive monomeric derivatives based on guanidine has been attempted in order to create novel polymer coatings suppressing activity of pathogens. Preliminary chemical interaction of these compounds with the epoxy component allows their covalent incorporation into the epoxy-amine network to ensure prolonged action of the coating. The synthesized guanidine hydrosalicylate, hydro-4-aminosalicylate, hydro-5-sulfosalicylate, and dihydro-5-sulfosalicylate have been characterized by means of elemental and thermal analysis. The degree of hydrochloride substitution with the organic salt residue and temperature of onset of the thermal decomposition under argon as well as temperatures of the salts vitrification and melting have been determined. Solubility of the synthesized salts in a diane-epoxy oligomer has been estimated. It has been shown that the substitution of hydrochloride with the organic residue noticeably decreases the temperature of the onset of the reaction with the epoxy oligomer. Average functionality of the guanidine salts in the reaction with the epoxy oligomer has been determined; it has been revealed that most of the N-H groups of the modifiers are involved in the reaction, in certain cases these being the residues of the organic salts. Stoichiometry of the guanidine-epoxy oligomer binary mixtures as well as this of the adducts synthesized with the oligomeric amine curing agent Jeffamine D-230 are presented. The initial tests of the obtained films have revealed pronounced bacteriostatic activity towards the methicillin-resistant S. Epidermidis at the guanidine hydrosalicylate content as low 1 wt %, the parameter of the film forming suppression being 19.2%.