The invention discloses a preparing method for thermosensitive
magnetic composite microspheres. Superparamagnetic microspheres are prepared through a hydrothermal method, subjected to
surface modification through a
silane coupling agent and then subjected to an
amidogen carboxyl association reaction with unsaturated olefine acid to introduce double bonds; on the other hand, N-isopropylacrylamide or a derivative of the N-isopropylacrylamide serves as a
monomer, sulfo ester serves as a
chain transfer agent, a
polymer with narrow molecular
weight distribution is synthesized through a reversible addition-fragmentation
chain transfer reaction under the action of an initiator, and then the prepared
polymer is subjected to a reduction reaction under the effect of a nucleophilic
reagent and a
reducing agent; lastly, the thermosensitive
magnetic composite microspheres are prepared through a
click chemistry reaction. The microspheres have magnetic responsiveness and thermosensitivity, magnetic responsiveness is high, the saturated
magnetic intensity ranges from 30 emu / g to 56.8 emu / g, and the particle size of the microspheres ranges from 290 nm to 590 nm. According to the preparing method, raw materials are easy to obtain, and the particle size of the prepared microspheres is controllable; the microspheres can be applied to the fields of
medicine controlled release, intelligent separation and the like.