(643g) Self Assembling Magnetic Nanostructures with Functional Polyolefin

Functional Polyolefin plastic additive, i.e., maleic anhydride grafted polypropylene (MAPP), has been used as polymeric surfactant for synthesizing magnetic nanostructures via a one-pot in-situ bottom up wet chemistry method. The MAPP was found to serve as stabilizer to stabilize and direct the self assembly patterns/morphology of these magnetic nanostructures. Here, one dimensional nanochains including iron, cobalt, and iron-cobalt alloy will be demonstrated. In addition, the macro-assembly patterns including one-, two-, and three dimensional morphologies will also be presented. The structure manipulation mechanism were studied and the results indicated that it is primarily controlled by the surfactant tail length, capping head density, surfactant-reactant mole ratio, surfactant molecular weight, and surfactant concentration. The force balance by magnetic attraction forces (from magnetic dipolar-dipolar forces) against the repulsive forces (from the steric hindrance of surfactant long chains) were also studied and discussed in detail. The crystalline structures of iron and cobalt nanostructures were also found to be controllable by MAPP with different reaction parameters. The magnetic properties of the synthesized nanostructures will be presented and the difference will also be discussed in detail.