Smart composites based on magnetic nanoparticles and responsive polymers

A comparative study of the properties of smart composites obtained by the combination of Fe 3 O 4 nanoparticles with biocompatible responsive polymers is reported. Two types of magnetic composites with different morphology were obtained: ( i ) as core-shell nanostructures consisting of Fe 3 O 4 functionalized by serine and covered with biocompatible polymer shell poly(caprolactone); ( ii ) as smart ferrogels, by the encapsulation of Fe 3 O 4 nanoparticles into chemically cross linked polymer like poly (N-isopropylacril amide). The composites formation and their characteristics as structure, chemical composition, magnetic behaviour were investigated by XRD, FTIR, XPS and magnetic measurements. The magnetic properties of the smart composites tailor as a function of magnetite content. Both types of magnetic composites show superparamagnetic behaviour. Higher magnetization values were obtained for the composites with the functionalized magnetite core covered by poly(caprolactone) as compared with the ferrogels.