表面含羧基的磁性高分子微球的制备和表征

Preparation and Characterization of Magnetic Polymer Microspheres with Surface Carboxyl Groups

以共沉淀法制备的Fe3O4为磁性来源,选用丙烯酰胺、N,N′-亚甲基双(丙烯酰胺)和丙烯酸分别作为聚合单体、交联剂和功能基单体,通过反相乳液聚合,包裹制备携带羧基的磁性高分子微球。考察了Fe3O4投入量、功能基单体量、交联剂量、聚合时间和介质的变化对磁性高分子微球的形态、磁性质及表面羧基含量的影响。采用SEMI、R、721E分光光度计和化学滴定法进行表征,制备出粒径在500 nm^10μm,表面羧基携带量为1.0 mmol/g的磁性高分子微球。

A method for producing polymer-coated magnetic microspheres with surface carboxyl groups by inverse emulsion polymerization is described. Experiments were performed with acrylamide monomer, ammonium persulfate initiator, F2O4 magnetic particles, acrylic acid functional group monomer and N, N＇-methylene bisacrylamide crosslinking agent. Five factors which influence the morphology, magnetic properties and amount of surface carboxyl groups of the magnetic polymer microspheres were taken into account： amount of F3O4, amount of acrylamide-acrylic acid, amount of N, N＇-methylene bisacrylamide, reaction time and medium. The properties of the magnetic polymer microspheres were charactered by SEM, IR spectroscopy, 721E spectrophotometer and chemical titration. Spherical magnetic polymer particles with 1.0 mmol/g carboxyl groups and the size from 500 nm to 10 μm were obtained.