title: Influence of iron oxide nanoparticles on the rheological properties of hybrid chitosan ferrogels.
abstract: Magnetite nanoparticles have been successfully synthesized in the presence of chitosan using an in situ coprecipitation method in alkali media. This method allows obtaining chitosan ferrogels due to the simultaneous gelation of chitosan. The chitosan concentration has been varied and its effects on the particle synthesis investigated. It has been demonstrated that high chitosan concentrations prevents the formation of magnetite due to the slow diffusion of the alkali species through the viscous medium provided by chitosan, instead iron hydroxides are formed. The presence of magnetite nanoparticles increases the elastic modulus which results in a reinforcement of the chitosan ferrogels. This effect is counterbalanced by the disruption of hydrogen bonding responsible for the formation of chitosan hydrogels in alkali media.
authors.affiliation: Instituto de Ciencia y Tecnología de Polímeros, CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain. rhernandez@ictp.csic.es
authors.forename: Rebeca
authors.initials: R
authors.lastname: Hernández
authors.forename: Vanessa
authors.initials: V
authors.lastname: Zamora-Mora
authors.forename: María
authors.initials: M
authors.lastname: Sibaja-Ballestero
authors.forename: José
authors.initials: J
authors.lastname: Vega-Baudrit
authors.forename: Daniel
authors.initials: D
authors.lastname: López
authors.forename: Carmen
authors.initials: C
authors.lastname: Mijangos
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D055119:Elastic Modulus; D005290:Ferric Compounds / Q000737:chemistry; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D012212:Rheology
chemical_list: D005290:Ferric Compounds; D020100:Hydrogels; C000499:ferric oxide; D048271:Chitosan; D052203:Ferrosoferric Oxide