The synthesis of functional Janus nanosheets as compatibilizers for the immiscible polyamide 6 /polystyrene (PA6/PS): Formation of the nanosilica monolayer at the interface

The non-spherical Janus nanosheets (JNSs) have been large-scale synthesized by grafting polystyrene (PS) chains and epoxy group on the opposite sides of JNS, denoted as epoxy-silica-PS JNS. The functional JNSs are employed as compatibilizer in the immiscible polyamide 6 (PA6)/polystyrene (PS) blend. In the melt-blending process, the JNS with epoxy group can react with carboxyl (amino)-capped PA6 and in-situ form the PA6-silica-PS JNS. Owing to the amphiphilicity and Pickering effect, the JNSs can be exclusively located at the polymeric interface and assemble into the nanosilica monolayer at 0.5 wt% loading. With increasing the JNSs loading, the size of dispersed PS phase is decreased gradually and the JNSs still maintain the single layer structure at the interface. The dynamic moduli of the blends have been effectively improved for the JNSs at the interface. This report provides an extended application of Janus nanosheets to stabilize and functionalize the polymeric interface.