Fe3O4磁性纳米颗粒的RAFT试剂化研究

通过反相微乳液法制备四氧化三铁纳米颗粒(Fe₃O₄ NPs),并用硅烷偶联剂KH570对其改性,以期在Fe₃O₄ NPs表面引入C==C双键,再利用引入的C==C双键与三硫代十二烷酸-2-氰基异丙酯(RAFT试剂)进行反应,得到RAFT试剂化的Fe₃O₄ NPs(Fe₃O₄-g-KH570-RAFT NPs),并对不同阶段的Fe₃O₄ NPs产物的结构与形貌等进行表征.研究中以RAFT试剂接枝率(Gr_RAFT)为指标,考察了反应时间等工艺条件对Gr_RAFT的影响.结果表明:制备的Fe₃O₄-g-KH570-RAFT NPs的平均粒径为10.4 nm,当反应时间为14 h,反应温度为65 ℃,n_KH570/n_RAFT为1/2时,接枝率Gr_RAFT最高达到79.34%.

Functionalization of Fe3O4 magnetic nanoparticles using RAFT reagent

Ferric oxide nanoparticles (Fe₃O₄ NPs) were prepared in this study by reverse microemulsion method, and modified by silane coupling agent KH570 so as to introduce cellulc double bond on the surface of Fe₃O₄ NPs, and then react with 2-cyanopropan-2-propanyl dodecyl trithiocarbonate to obtain RAFT reacted Fe₃O₄ NPs (Fe₃O₄-g-KH570-RAFT NPs)). The structure and morphology of Fe₃O₄ NPs products at different stages were also characterized. Effects of reaction time and other process conditions on Gr_RAFT were investigated quantitatively in the study by taking the grafting rate of RAFT reagent (Gr_RAFT) as an index. The results show that the average particle size of the prepared Fe₃O₄-g-KH570-RAFT NPs is about 10.4 nm. When the reaction time takes 14 h, the reaction temperature is 65 ℃, and n_KH570/n_RAFT becomes 1/2, the highest grafting rate Gr_RAFT may reach up to 79.34%.