Waste plastic based hypercrosslinked polymer with adjustable pore size as well as preparation method and application thereof

The invention provides a preparation method of a waste plastic based hypercrosslinked polymer with an adjustable pore size. The preparation method comprises the following steps: mixing polystyrene foamed plastics with 1,2-dichloroethane and methylal, fully dissolving the mixture, adding anhydrous ferric chloride for catalysis for performing a single-step crosslinking reaction or performing secondcrosslinking after pre-crosslinking with acetic acid and methylal, and performing purification, so as to obtain the hypercrosslinked polymer with the adjustable pore size and high specific surface area. Compared with a molecular sieve, zeolites and various commercial activated carbons that are used in the market, the hypercrosslinked polymer obtained by the preparation method has the advantages ofbeing obvious in removing effect and being low in cost; the preparation method provided by the invention is mild in process, and the waste polystyrene foamed plastics are turned into wealth, so thatthe problem that the enviro