分散聚合法制备液相芯片聚苯乙烯磁性复合微球的研究

本文将丙烯酸基磁流体均匀分散到苯乙烯单体中,采用分散聚合法制备出了适于构建液相芯片微球载体的单分散性微米级磁性微球.考察了丙烯酸基磁流体预处理时间、加料顺序和单体量对微球形貌和粒径分布的影响及其条件优化.扫描电镜(SEM)显示磁性微球平均粒径为7.77 μm,具有良好的单分散性(多分散指数PDI为1.03),并且表面光滑致密；用超导量子干涉磁强计测量了Fe3O4纳米粒子的磁化曲线；用红外光谱(FT-IR)和热失重(TG)方法表征了磁性微球的化学结构及Fe3O4含量.

Preparation of polystyrene magnetic microspheres for liquid chips by dispersion polymerization

We present an approach of synthesizing magnetic polystyrene complex microspheres by a facile dispersion polymerization.Monodisperse magnetic polystyrene microspheres,appropriate to construct liquid chip carriers,were prepared via dispersion polymerization by dispersing pre-treated acrylic acid-based magnetic fluid in styrene.The effects of synthetic conditions such as pretreatment time of acrylic acid-based magnetic fluid,feeding sequence and amount of styrene monomer on particles’conformation and their size distribution have been investigated,and parameters were further optimized accordingly.SEM results indicate that the magnetic microspheres have an average diameter of 7.77 μm with excellent monodispersity(PDI 1.03) and smooth and compact surfaces.Magnetization curve of Fe 3 O 4 nanoparticles was obtained using superconducting quantum magnetometer.Chemical structures and content of magnetic Fe 3 O 4 of the microspheres were characterized and analyzed using FT-IR and TGA methods.