SPECIFIC FEATURES OF THE STRUCTURE OF CRO SS-LINKED POLYURETHANES BASED ON VARIOUS DIISOCYANATES CROSS-LINKED BY COPPER IONS AND THE COMPLEXES OF COPPER WITH CROWN-ETHERS

Cross-linked polyurethanes were synthesized from oligotetramethylene g lycol 1000, tolylene diisocyanate, diphenylmethane diisocyanate and we re then cross-linked by copper ions or their complexes with crown ethe rs (dibenzo-18-crown-6 or dibenzo-24-crown-8). The structure of polyme rs was studied by small-angle X-ray scattering and stress relaxation u nder constant strain. The structuration induced by chemical crosslinki ng with copper ions or their complexes with crown ethers was shown to occur concomitantly with the structuration associated with thermodynam ic incompatibility of the polymer segments whose hard blocks had diffe rent diisocyanate fragments.