聚（N-异丙基丙烯酰胺-co-丙烯酸）/Fe3O4复合微球的制备及表征

采用Fe3O4、N-异丙基丙烯酰胺(NIPAM)和丙烯酸(AA)制备了具有磁敏、温敏和pH敏感的多重敏性复合微球。先使用共沉淀法制备Fe3O4磁性纳米颗粒,并用油酸对其改性。继而采用种子聚合法制备P(NIPAM-co-AA)磁性微球。研究表明,在pH值为10的合成条件下,复合微球的分散性较好。采用疏水性引发剂可相对增加有机、无机相之间的亲和性。通过扫描电镜(SEM)、红外光谱(FT-IR)、动态光散射(DLS)和超导量子干涉磁强计(SQUID)等对微球进行了结构与形态表征,结果证明,复合微球形貌统一,各组分之间聚合良好。复合微球的粒径约为249 nm,对温度、pH可作出预期的响应,饱和磁化强度为40 emu/g。

Preparation and Characterization of P（NIPAM-co-AA）/Fe3O4 Composite Microspheres

Multi-sensitive composite microspheres were fabricated using Fe3O4,N-isopropylacrylamide(NIPAM) and acrylic acid(AA).The Fe3O4 nanoparticles were prepared by co-precipitation method and modified by oleic acid.Composite microspheres were then prepared by seed polymerization method.The results show that the microspheres have better dispersion ability when reaction pH value is 10.The compatibility between the organic phase and inorganic phase could be enhanced using the hydrophobic initiator in this system.The products were characterized by scanning electron microscope(SEM),Fourier Transform infrared spectroscopy(FT-IR),dynamic light scattering(DLS) and superconducting quantum interference device(SQUID).It is found to be that the microspheres are uniformly distributed and the average diameter of composite microspheres is about 249 nm.The products have expected sensitivity to the temperature and pH.The saturated magnetization of microspheres can reach 40 emu/g.