四氧化三铁磁性纳米微粒表面的氨基化修饰

以3-氨丙基三乙氧基硅烷(APTES)作为氨基化试剂,通过硅烷化反应使其键合于Fe3O4纳米颗粒表面,制备了表面氨基化的磁性Fe3O4纳米复合颗粒;利用红外光谱分析了产物的化学键合特征,利用电位滴定测定了合成产物表面的-NH2含量,探讨了活化方式、反应溶剂、投料比、温度、时间等因素对氨基化修饰效果的影响.结果表明,APTES成功地包覆在磁性Fe3O4纳米微粒表面;在乙醇-水体系中,在Fe3O4与APTES投料比3∶8、温度60℃下反应12h,得到的Fe3O4纳米颗粒表面APTES修饰效果最佳,表面-NH2含量高达1 400±50μmol·g-1.

Amination surface-modification of ferriferous oxide magnetic nanoparticles

3-Aminopropyl triethoxysilane （APTES） was used as the amination agent and coated onto the surface of ferriferous oxide （Fe3O4） magnetite nanoparticles via silanization reaction. The chemical bonding feature of as-synthesized APTES-coated Fe3O4 nanoparticles was ana- lyzed by Fourier transform infrared spectrometry, and its surface -NH2 content was determined by potentiometric titration technology. Furthermore, the influences of activation method, sol- vent, feeding ratio, reaction temperature, and reaction time on the modification effect of Fe3O4 nanoparticles by -NH2 group were investigated. Results show that Fe3O4 nanoparticles have been successfully coated by APTES. The best surface-modification effect is reached after Fe3O4 nanoparticles are coated with APTES at a feeding ratio of 3 ： 8 and a temperature of 60℃ for 12 h in the presence of ethanol/water as the solvent. Resultant surface-modified Fe3O4 nanoparticles have a surface -NH2 content of about 1400 ±50 μmol .g-1.