Compatibilization of immiscible polymer blends using graphene oxide sheets.

By taking the advantage of the unique amphiphilic structure of graphene oxide sheets (GOSs), we develop here a new and effective strategy for compatibilizing immiscible polymer blends. With the incorporation of only 0.5 wt % GOSs into immiscible polyamide/polyphenylene oxide (PA/PPO, 90/10) blends, the droplet diameter of the dispersed minor phase (PPO) is dramatically reduced by more than 1 order of magnitude, indicating a largely improved compatibility in the GOS-filled polymer blends. As a result, the ductility of GOS-compatibilized polymer blends is notably elevated. The compatibilizing effect of GOSs should be due to the fact that GOSs can exhibit strong interactions with both PA and PPO phases, thus minimizing their interfacial tension. Moreover, unlike traditional copolymer compatibilizers, GOSs can also act as reinforcing fillers in polymer blends, thus remarkably enhancing their mechanical strength and thermal stability. Considering the inexpensive sources (graphite powders) and extraordinary properties of GOSs, this work may open up opportunities to produce new compatibilizers that are of great interest in the industrial field.