Synthesis and properties of a monolithic gradient polymer material based on polyurethane structures and 1,4-butanediol as a chain extender

Conditions of preparing monolithic gradient polymeric materials based on aliphatic polyether Laprol 5003 (Voranol 4711), 2,4-tolylene diisocyanate, and 1,4-butanediol as a chain extender have been studied. The materials have been synthesized on a semiautomatic lab molding machine that makes it possible to control the feed rate of precursors; therefore, the chemical structure of the material may be changed in the desired direction. As a consequence, the elastic modulus of the material changes along the sample length from 19 to 410 MPa; that is, the gradual transition from a low-modulus plastic to a rigid rubber occurs. The introduction of 1,4-butanediol improves the viability of precursors and thus hampers the occurrence of premature gelation and creates wide possibilities for obtaining both monolithic and composite reinforced gradient polymeric materials.