Effect of nano MMT and mesoporous MCM-41 on corrosion resistance of poly (propylene carbonate) - based waterborne polyurethane

Environmental friendly poly (propylene carbonate)-based waterborne polyurethane (PPC-based WPU) is prepared with PPC and isophorone diisocyanate (IPDI) as the soft segment and the hard segment, respectively. In this reaction system, 2,2-dimethylolbutyric acid (DMBA) is used as the hydrophilic donor and trimethylolpropane (TMP) as the crosslinking agent. The effect of co-doping of layered montmorillonite (MMT) and mesoporous material MCM-41 on corrosion resistance of PPC-based WPU resin was studied. The properties of the samples were characterized with N-2 physical adsorption, XRD, FT-IR, TG-DTA, DSC and water absorption testing. Potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and salt spray test were employed to investigate the corrosion performance of all the coatings. The results of XRD indicate that the MMT in the composite polyurethane resin is peeled off and MCM-41 maintains the hexagonal framework structure after grinding. Compared with the WPU coatings with MMT or MCM-41 single incorporation, those with MMT and MCM-41 co-incorporation show the best corrosion resistance, which is due to the different interface structure between filler and resin matrix.

Automated summary

The effect of co-doping of layered montmorillonite (MMT) and mesoporous material MCM-41 on the corrosion resistance of PPC-based WPU resin was studied. The results showed that the coatings with MMT and MCM-41 co-incorporation exhibited the best corrosion resistance, attributed to the different interface structure between filler and resin matrix.