Methylaluminoxane (MAO) activates various transition metal catalysts for coordination polymerization reactions and exists as a counter anion that can interact with cationic metal species in a polymerization medium. The structural modifications to MAO would therefore provide a new direction for controlling the polymerization behavior. In this review, our recent work about the modification, the composition control, and a new preparation method of MAO is summarized. The application of modified MAO for the synthesis of stereoblock polydienes is also described.
