Preparation and characterization of maltodextrin-based polyurethane

Maltodextrin (MD) based polyurethane (MDPU) was prepared by the reaction of MD and polyethyleneglicol (PEG) polyurethane prepolymer (PUP). The structure and properties of the MDPU were investigated by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (H-1 NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscope (SEM), Energy dispersive X-ray spectrometry (EDS), and tensile-testing machine in detail. Chemical structure of MDPU was confirmed by FTIR and H-1 NMR. MDPU with 66.7% of PUP (MDPU-0.5) was a thermoset plastic with good elasticity but the others (MDPU-1, MDPU-2, and MDPU-3) were thermoplastics. TGA analysis showed that the MDPUs exhibited three stages of the thermal degradation, mainly including urethane linkage (I, 197-268 degrees C), MD and PUP components (II, 268-380 degrees C) and the formed stable structures during thermal degradation (III, 400-505 degrees C), respectively. The various degrees of miscibility were presented. The mechanical properties of thermoplastic MDPUs exhibited relatively high elongation at break under the given relative humidity.