摘要：为解决天然壳聚糖 (CTS) 作为CO₂开关型乳化剂时响应破乳不完全的问题, 对CTS进行磁性Fe₃O₄纳米粒子的接枝改性;采用红外光谱和扫描电子显微镜对接枝改性产物进行表征, 并测试其CO₂响应性、乳化性能及破乳效果。结果表明:磁性Fe₃O₄纳米粒子成功接入CTS, 并在水中形成CTS包覆磁性Fe₃O₄纳米粒子的聚集体颗粒;Fe₃O₄纳米粒子的接入并不会影响壳聚糖的CO₂响应性和乳化性能;磁化改性CTS制备的乳液在CO₂作用下, 不能完全破乳的情况可在磁性协同作用下发生改善, 达到完全的破乳分层。

关键词：磁性 Fe₃O₄ 纳米粒子；改性；壳聚糖；CO₂ 开关型乳化剂；磁性协同破乳

Abstract：The emulsion stabilized by natural chitosan can not be demulsified completely by the effect of CO₂ when chitosan is used as a CO₂-switchable emulsifier. In order to resolve this problem, the magnetic Fe₃O₄ nanoparticles have been grafted in chitosan.The FT-IR and SEM tests confirm that the magnetic Fe₃O₄ nanoparticles are grafted in the chitosan structure successfully, and the product aggregate in water with a shape of chitosan coat magnetic Fe₃O₄ nanoparticles. The conductivity experiments confirm that the grafting of Fe₃O₄ nanoparticles does not affect the CO₂-responsive capability of chitosan, while the emulsification experiments confirm that the grafting does not affect the emulsification capability of chitosan. The CO₂-magnetic experiments illustrate that the emulsion stabilize by the Fe₃O₄ nanoparticles-graft chitosan can be demulsified completely in the synergistic reaction of CO₂ and magnetic.

Keywords：magnetic Fe₃O₄ nanoparticles；modification；chitosan；CO₂-switchable emulsifier；magnetic synergistic demulsification