首先通过乳化法得到磁性明胶微球,然后在高速搅拌条件下向乳液中直接加入正硅酸乙酯(TEOS),制备出多孔磁性明胶微球.用SEM,TEM观察了微球的微观形貌,发现微球呈疏松多孔状结构.用FT-IR,TGA,VSM等测试手段对微球的结构和性能进行表征.结果表明,二氧化硅掺杂于磁性明胶微球中.TEOS在反应中作为明胶微球的交联固化剂,推测其固化机理是物理交联固化.实验证实二氧化硅改性后,磁性明胶微球内部磁性颗粒氧化速度有所降低.所得到的多孔磁性明胶微球表现出铁磁性.
The porous magnetic gelatin microspheres were prepared as follows: firstly, the magnetic gelatin microspheres were obtained by an emulsion method and then tetraethyl orthosilicate (TEOS) was directly added into the emulsion system under vigorous stirring. The morphologies of the microspheres were observed by SEM and TEM. The structure and properties of the microspheres were characterized by FT-IR, TGA and VSM. The results showed that the silica was intermingled into the magnetic gelatin microspheres. The TEOS acted as a cross-linking hardening agent in the system. The results illustrated that the oxidation speed of the magnetic nanoparticles in the porous magnetic gelatin microspheres was slower than that in the magnetic gelatin microspheres. The porous magnetic gelatin microspheres displayed ferromagnetism properties.