The Preparation And Characterization Of PAMAM Dendrimers Composite Magnetic Particle

Nanometere Fe₃O₄ were prepared by chemical co-precipitation method using FeCl₂·4H₂O and FeCl₃·6H₂O as raw materials, as well as NH₃·H₂O used as precipitator to control the pH value. A series of experiments were conducted to review the influence factors for the performance of the obtained Fe₃O₄, such as the dosage of NH₃·H₂O, the ratio of Fe²⁺: Fe³⁺, whether to use dispersant or not, the stabilization time. The resultants were characterized by XRD, TEM and SQUID. The results showed that the Fe304 owned the shape of sphericity and the superp aramagnetic with the grain diameter of 10 nm, which could meet the needs of magnetic core used in magnetic macromolecule particles.With the nanometere Fe₃O₄ as magnetic core, with the NaOH to control the pH value during the experiments, PSt-acrylamide magnetic particles were synthesized by emulsion polymerization method, using styrene, acrylamide as raw materials, BPO asinitiator, SDS as emulsifier and DVB as divinylsulfone. A variety of experiments were conducted to reviewed the impact factors for the performance of PSt-acrylamide magnetic particles, including the dosage of Fe₃O₄ magnetic cores and acrylamide, whether to use divinylbenzene or not. The resultants were tested by XRD, TEM, FTIR, element analysiser and SQUID. The experiments indicated that the obtained magnetic particles were round, with HN2 active group on the surface, diameter of 100～300 nm, superparamagnetic, better suspensibility and magnetic responsiveness.4.0 G PAMAM dendrimer was obtained by divergent procedures, using diaminoethane, methyl acrylate as raw materials and methanol as solvent. The dosage of monomer, reaction temperature, reaction time were tested to review the product efficiency of PAMAM. It was also characterized by FTIR. The results showed that the PAMAM was rich in HN2 active group on the surface, which could meet the needs of enhancing the HN2 active group on the surface of magnetic particles.PSt-acrylamide magnetic particles were composited by using glutaraldehyde as active agent, 4.0 G PAMAM as stuff, and reviewed the influence factors whether to use active agent to enhance the effect of magnetic particles. It was characterized by FTIR, element analysiser and SQUID. The results showed that the mass percent of N in magnetic particle enhanced by PAMAM was increased obviously. It proved that PAMAM was coupled with magnetic particle, which provided more NH₂ active group for magnetic particle.