Relationship of hard segment concentration in polyurethane-urea elastomers with mechanical, thermal and drug release properties

The main aim of this research was to study the effects of size and concentration of the hard segments on thermal stability, solvent resistance, hardness and drug delivery applications in polyurethane-urea (PUU) elastomers. Four diamines having different aliphatic chains, were synthesized and used as chain extenders (CE) to synthesize PUU. NCO/OH ratio was changed from 2-2.5 to study the effect of concentration of hard segments. Structure, morphology, thermal stability, hardness, solvent resistance, drug delivery and mechanical properties of polyurethane-urea elastomers were examined by means of fourier transform infrared spectroscopy (FUR), wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), shore durometer, UV/Vis spectrophotometer and universal testing machine (UTM) respectively. (C) 2016 Elsevier B.V. All rights reserved.