Inorganic nanoparticles incorporated in polyacrylonitrile‐based mixed matrix membranes for hydrophilic, ultrafast, and fouling‐resistant ultrafiltration

ABSTRACT Mixed matrix membrane (MMM) structures and performances are greatly affected by the distribution of nanoparticles in the polymeric matrix. Until now, there has been little research on the effects of nanoparticle distribution states on polyacrylonitrile (PAN)‐based MMM structures and performances. In this paper, different intermolecular interactions between nanoparticles and PAN molecules were generated by in situ fabricated amino‐functionalized SiO 2 and TiO 2 nanoparticles to create absolutely different distribution states of nanoparticles in a PAN matrix. The results indicated that, due to the strong interactions between amino and cyano groups, SiO 2 is distributed in the PAN membranes homogeneously, while most of the TiO 2 migrates to the membrane's top surfaces or the walls of pores or even escape from the membranes during the nonsolvent index phase separation (NIPS) process. PAN‐TiO 2 MMMs have more hydrophilic top surfaces, higher porosity, larger mean pore size, and stronger antifouling performances than pure PAN and PAN‐SiO 2 membranes. The PAN‐TiO 2 MMMs have an ultrahigh water flux of 1204.6 L/(m 2 h), which is more than 44 times that of PAN membranes. And the good pore structures and hydrophilicity of the membranes derived from special interactions between in situ TiO 2 nanoparticles and PAN molecules can give high‐performance PAN‐based ultrafiltration membranes a bright future. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47902.