the present disclosure relates to the field of shape memory materials , it discloses a betaine - based shape memory polymer and the preparation method thereof . the polymer is formed through free radical polymerization of an unsaturated betaine monomer , an acrylic monomer , and an ethylene glycol divinyl ether monomer with the addition of an initiator . the betaine - based shape memory polymer has thermosensitive shape memory property and wet sensitive shape memory property , and it has good biocompatibility and an excellent shape memory property , antibacterial property . it is of great potential for use in engineering , construction , daily life and medical service .