preparation of hydroxyl unsaturated polyester: maleic anhydride and diol were added to a 500ml four-mouth bottle equipped with a stirrer, thermometer, nitrogen protection and condensation dehydration device, and reacted at 130-160 ℃ for 2h and 190-210 ℃ for 4h, with a yield of 98.0%.
Preparation of polyurethane: in a 500ml four-mouth bottle equipped with a stirrer, a reflux condenser tube, a thermometer and a protective device, accurately measured hydroxyl unsaturated polyester, solvent and diisocyanate are added, reacted at 70 ℃ for 4h, then diamine or diol is added, and the temperature is raised to 80 ℃ for 3h, and the yield is 94%.
Preparation of polyurethane macroporous copolymer: In a three-mouth bottle, 5% sodium chloride aqueous solution is added, polyvinyl alcohol is used as a dispersant, and a polymerization phase composed of polyurethane, alkene monomer, porogen and initiator is added. The bead macroporous resin is obtained by suspension polymerization. After hot water washing, acetone extraction, air drying, vacuum drying, the yield is above 90%.