Abstract:In this paper, P(NIPAM-co-St) thermosensitive nanoparticles were prepared by emulsion polymerization. The structure and properties of P(NIPAM-co-St) thermosensitive nanoparticles were characterized by FT-IR, DLS, SEM. The effects of the amount of styrene,crosslinking agent and emulsifier on the lower critical solution temperature (LCST), particle size and swelling properties of P(NIPAM-co-St) nanoparticles were studied. The results show that the lower critical solution temperature (LCST) decreases with the increase of the content of St and crosslinking agent, and the swelling rate is decreased also. With the increase of the amount of emulsifier, LCST and the swelling rate are almost unchanged, the particle size decreases sharply with the amount of emulsifier between 0～3%, when the amount of emulsifier is more than 3%, the particle size does not change significantly.