ПІДВИЩЕННЯ ГІДРОЛІТИЧНОЇ СТІЙКОСТІ ПЛІВОК ПОЛІУРЕТАНОВИХ ІОНОМЕРІВ, ЩО ВИКОРИСТОВУЮТЬСЯ ДЛЯ ПІГМЕНТНИХ ЗАБАРВЛЕНЬ

Abstract

The paper reports the results of the study on the hydrolytic stability of films obtained from aqueous dispersions of polyurethane ionomers of sulfonate and carboxylate types, in particular the effect of the process duration of films in aqueous solutions of soda and surface-active substances on the bursting tension during stretching was investigated. This indicator is important when using dispersions as binders in pigment compositions for the printing of textile materials, because the indicators of the stability of colorings to wet treatments, in particular to washing, depend on the properties of dispersions. It was found that the investigated polyurethane ionomers do not provide the stability indicators, which would be expected from a polyurethane nature of the binder. An assumption was made that this results from an insufficient stability of some polyurethanes to hydrolysis. For increasing the polymer stability to hydrolysis and the stability of colorings to wet treatments, we tested the possibility of increasing the density of a three-dimensional structure of polyurethane. To this end, pre-condensates of thermosetting resins, which are widely used in finishing works, were used. An increase in the stability of both films of polyurethane ionomers and the coloring formed was stated when using the binders of the specified type in the presence of precondensates of thermosetting resins. The mechanism of the action of the pre-condensates of thermosetting resins was determined in the formation of polyurethane films. It was established that a high efficiency of additives of pre-condensates of thermosetting resins towards the polyurethane binder is ensured by the resin formation and the formation of a composite-type film with increased strength characteristics on the surface of a fabric. The formation of a polymer system of the specified type provides high coloring stability and improves performance characteristics of a textile material.