Modification of polymer surfaces based on polyurethanes with photochromic compounds.

The possibility of covalent fixing of hydroxyl-containing photochromic compounds on the surface of polyurethane films containing excess isocyanate groups was studied. By comparing the spectral-kinetic characteristics of polyurethane films treated with solutions and films with chromene or spirooxazine derivatives introduced into the bulk polymer, it was concluded that in the first case the polymer swells and the photochromic compound becomes distributed predominantly in the bulk polymer rather than on the surface. [ABSTRACT FROM AUTHOR]