Mixed matrix membranes for gas separation: Challenges and Perspective

The concept of mixed matrix membranes (MMMs) comprising rigid particles dispersed in a continuous polymeric matrix was proposed to improve the separation properties of polymeric membranes. In this approach, the good advantages of both polymeric matrix and inorganic fillers combined and a good permeable membrane with high selectivity, chemical stability, mechanical strength and processability can be prepared. In this article, factors affecting the performance of MMMs where reviewed. Also, the types of MMMs by structure, preparations methods were discussed. In addition, types of common inorganic fillers, gas transport mechanism in MMMs, stress and defects in polymer/inorganic interface and the most prevalent models which can predict the performance of MMMs were stated and discussed. Finally, the future directions of researches in this context and potential usages of MMMs where shown.