Preparation and characterization of magnetic composite microspheres using a free radical polymerization system consisting of DPE
Preparation and characterization of magnetic composite microspheres using a free radical polymerization system consisting of DPE
复制标题
DOI：
10.1016/j.polymer.2009.02.023
复制
发表时间：
2009-04
期刊：
影响因子：
4.6
通讯作者：
Feige Guo;Qiuyu Zhang;Baoliang Zhang;Hepeng Zhang;L. Zhang
中科院分区：
文献类型：
--
作者：
Feige Guo;Qiuyu Zhang;Baoliang Zhang;Hepeng Zhang;L. Zhang
本文采用自由基聚合法制备了磁性复合微球。以丙烯酸、甲基丙烯酸甲酯和苯乙烯为单体，在Fe 3 O 4纳米粒子存在下，以二苯乙烯（DPE）为自由基控制剂，通过共聚反应合成了Fe 3 O 4/P（AA-MMA-St）核壳型磁性复合微球。采用FTIR、1H NMR、SEC-MALLS、TEM、TGA、VSM等仪器对磁性复合微球的结构和性能进行了分析，并根据这些结果推测了复合微球的形成机理。结果表明，Fe_3O_4/P（AA-MMA-St）微球为纳米级，粒径分布相对均匀，球形形貌完整，具有超顺磁性，饱和磁化强度为18.430emu/g，磁含量高达40%。甲基丙烯酸甲酯生成并吸附在Fe 3 O 4纳米粒子表面。接触角分析表明，含DPE的共聚物通过化学吸附提高了Fe 3 O 4纳米粒子的疏水性。在第二步聚合中，一定量的苯乙烯单体和残余的甲基丙烯酸酯单体在Fe_3O_4纳米粒子表面引发聚合，形成Fe_3O_4/P（AA-MMA-St）复合微球。
In this paper, a free radical polymerization system consisting of DPE was used to prepare magnetic composite microspheres. Fe3O4/P(AA–MMA–St) core-shell magnetic composite microspheres have been synthesized by copolymerization of acrylic acid, methyl methacrylate and styrene using DPE as radical control agent in the presence of Fe3O4nanoparticles. The structure and properties of the magnetic composite microspheres were analyzed by FTIR,1H NMR, SEC-MALLS, TEM, TGA, VSM and other instruments, and the formation mechanism of composite microspheres was supposed by those results. It was found that the Fe3O4/P(AA–MMA–St) microspheres were nano-size with relatively homogeneous particle size distribution, perfect sphere-shaped morphologies, superparamagnetism with a saturation magnetization of 18.430emu/g, and high magnetic content with a value of 40%.1H NMR and TEM analysis indicated that at the first stage of polymerization, a DPE-containing copolymer of acrylic acid, methyl methacrylate formed and was then absorbed on the surface of Fe3O4nanoparticles. Contact angle analysis indicated that the DPE-containing copolymer improved hydrophobicity of Fe3O4nanoparticles through chemical absorption. In the second step polymerization, certain amount of monomers of styrene and residue methacrylate were initiated by the DPE-containing copolymer on the Fe3O4nanoparticles' surface and resulted in the formation of Fe3O4/P(AA–MMA–St) composite microspheres.