Method for preparing modified methylaluminoxane through multi-step hydrolysis by adopting microreactor combination

The invention discloses a method for preparing modified methylaluminoxane through multi-step hydrolysis by adopting a microreactor combination. The method comprises the following steps: dispersing water with an inert solvent, conveying the dispersed water to a micro-mixer M1 to be mixed with an aluminum alkyl AlR3 solution, and conveying a mixed stream into a micro-reactor R1 to react, so as to obtain an alkylaluminoxane product; and mixing the alkylaluminoxane product and an alkylaluminum AlR '3 solution in a micro-mixer M2, conveying the obtained mixed solution to a micro-mixer M3, dispersing and conveying water to the micro-mixer M3 through an inert solvent, and conveying the mixed material fully mixed by the micro-mixer M3 to a micro-reactor R2 for reaction to obtain the modified methylaluminoxane product. Effective micro-dispersion of water in the inert solvent can be achieved, then mixed hydrolysis of multiple alkylaluminoxane is achieved, the whole reaction process is efficient, safe and controllable,