Structure–property relationships of polyurethane‐based materials (PUPA) for applications in biomedicine

Polyurethane poly(amido–amine) (PUPA) is a modified polyurethane whose chains are crosslinked with those of a tertiary aminic polymer [poly(amido–amine) (N 2 LL)] by the bifunctional agent hexamethylenediisocyanate (HMDI). PUPA is capable of complexing heparin; a behavior that is related to the presence of poly(amido‐amine). The effect of the chemical composition of the starting mixture and/or the reaction time on the morphology and physical properties was studied by using differential scanning calorimetry, dynamic mechanical experiments, x‐ray, scanning electron microscopy, and Fourier transform infrared attenuated total reflection analyses.