Spherical Polyelectrolyte Brush as Robust Scaffold for Size-controlled Synthesis of Magnetic Nanoparticles
writer：Zhu, Yan; Chen, Kaimin; Li, Li; Guo, Xuhong
keywords：无
source：会议
specific source：Polymeric Materials: Science and Engineering, 2011, 104, 428-429
Issue time：2011年
Magnetic nanoparticles (MNP) with narrow size-distribution were successfully synthesized in a novel scaffold of spherical polyelectrolyte brush. The magnetic composite brush particles were very stable after the attachment of MNP. The NMP were tightly attached onto PAA chains through coordination between carboxyl groups in PAA and active iron atoms on the surface of MNP. Reverse feeding sequences have been introduced to offer different alkalinity for formation of MNP which resulted in different morphology, dispensability and size-distribution of prepared MNP. When the scaffold structure changed to crosslinked microgel, the nucleation and subsequent growth of MNP were changed. The magnetic properties of well-ordered nanoparticles in polymer matrix showed obvious transition from superparamagnetism to ferromagnetism resulted from dipole-dipole interactions between neighboring nanoparticles.