Herein

the conventional preparation methods of cationic polymer microsphere

highlighting the progress of (emulsifier-free) emulsion polymerization

dispersion polymerization

microemulsion polymerization

as well as the application in profile conformation

electrorheology fluid

biomedicine

are reviewed

and origin of cationic charges in the microsphere surface and cationic monomers used in world-wide published works are systematically summed up. Moreover

the specifications of various processes for preparation are elucidated. Recently

a number of new methods like clicking chemistry

atom transfer radical polymerization for this use have paved a way for the control of surface property of microsphere. Thus

the outline on the future directions and challenges come with the design and engineering of cationic polymer particles is concluded.