title: Preparation of SiO2/(PMMA/Fe3O4) from monolayer linolenic acid modified Fe3O4 nanoparticles via miniemulsion polymerization.
abstract: SiO2/(PMMA/Fe3O4) composite particles were prepared from linolenic acid (LA) instead of oleic acid (OA) modified Fe3O4 nanoparticles by miniemulsion polymerization. LA has three unsaturated double bonds with which it can polymerizate more easily than OA. And coating Fe3O4 with polymethyl methacrylate (PMMA) polymer beforehand can prevent magnetic nanoparticles from the aggregation that usually comes from the increasing of ionic strength during the hydrolyzation of tetraethoxysilane (TEOS) by the steric hindrance. Finally, the resulting PMMA/Fe3O4 nanoparticles were coated with silica, forming SiO2/(PMMA/Fe3O4) core-shell structure particles. The sizes of nanoparticles with core-shell structure were in the range from 300 to 600 nm. The nanoparticles were spherical particles and had consistent size. The result of magnetic measurement showed that the composite particles had superparamagnetic property.
authors.affiliation: School of Public Health, Southeast University, Nanjing 210009, China.
authors.forename: Lei
authors.initials: L
authors.lastname: He
authors.forename: Zhiyang
authors.initials: Z
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Fu
authors.forename: Yan
authors.initials: Y
authors.lastname: Deng
authors.forename: Nongyue
authors.initials: N
authors.lastname: He
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Zhiyang
authors.initials: Z
authors.lastname: Shi
authors.forename: Zunliang
authors.initials: Z
authors.lastname: Wang
mesh_terms: D003460:Crystallization / Q000379:methods; D004655:Emulsions / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008280:Magnetics; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D017962:alpha-Linolenic Acid / Q000737:chemistry*
chemical_list: D004655:Emulsions; D005290:Ferric Compounds; D046911:Macromolecular Substances; D011108:Polymers; D017962:alpha-Linolenic Acid; C000499:ferric oxide; D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate