Effect of poly(sodium 4-styrenesulfonate) modified carbon black on the dispersion and properties of waterborne polyurethane nanocomposites

In this work, the poly(sodium 4-styrenesulfonate) modified highly hydrophilic carbon black (PCB) have been successfully prepared by one-step in situ ball milling method. The resulting PCB exhibited an excellent dispersion in water with an encapsulation of 14.9 wt%. The results of laser particle analyzer showed that the PCB exhibited the smallest particle size of 127 nm at the pH of 5 in water. The PCB was firstly used to prepare blend films with waterborne polyurethane (WPU) emulsion and the effect of PCB content on the structure and properties of the resultant films were discussed. The excellent dispersibility of PCB in WPU emulsion through electrostatic repulsion was observed, which played an important role in improving the homogeneous structure of blend films. Compared with the neat WPU films, the tensile strength of the WPU/PCB hybrid films increased from 39.8 to 54.2 MPa and the break elongation decreased from 1200 to 827%.