Waterborne Poly(urethane-urea)s Nanocomposites Reinforced with Clay, Reduced Graphene Oxide and Respective Hybrids: Synthesis, Stability and Structural Characterization

Nanocomposites based on waterborne poly(urethane-urea)s (NWPUU) containing hydrophilic montmorillonite (MMT) clay, reduced graphene oxide (rGO) or MMT/rGO hybrids were produced by a green synthesis method. Polymer matrices were based on poly(ethylene glycol- block -propylene glycol) (PEG- b -PPG) (with different contents of PEG-based segments), poly(propylene glycol) (PPG), isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA) and hydrazine. Aqueous dispersions were characterized in terms of particle hydrodynamic diameter (D H ) and rheological parameters and respective cast films were investigated by X-ray diffraction (XRD), low-field nuclear magnetic resonance (NMR) relaxometry and Fourier-transform infrared spectrometry (FTIR). Pseudoplastic dispersions with D H