Polyolefin catalyst using spherical double-mesoporous composite material as carrier, polyolefin and preparation methods of polyolefin catalyst and polyolefin

The invention relates to the technical field of homogeneous catalysis olefin polymerization reactions, and discloses a method for preparing a polyolefin catalyst, the polyolefin catalyst prepared by the method, an olefin polymerization method and polyolefin prepared by the method. The method for preparing the polyolefin catalyst comprises: (a) preparing a two-dimensional hexagonal mesoporous material filter cake; (b) preparing a silica gel filter cake; (c) carrying out ball milling or sequentially carrying out mixing and ball milling on the mesoporous material filter cake and the silica gel filter cake, washing the ball-milled product by using a ceramic membrane filter, and carrying out spray drying to obtain a spherical double-mesoporous composite material carrier; and (d) loading a magnesium component and/or a titanium component on the carrier. According to the invention, the method is efficient, simple, energy-saving and environment-friendly, and the prepared polyolefin catalyst ishigh in activity, and can