Magneto-sensitive hybrid nanocomposites of water-soluble sodium alginate cross-linked with calcium ions and maghemite

eXPRESS Polymer Letters

V. V. Spiridonov¹ 

关键词: polymer composites;    nanocomposites;    biodegradable polymers;    magnetic;    nanoparticles;   

DOI  :  10.3144/expresspolymlett.2018.38

学科分类：生物科学（综合）

来源: eXPRESS Polymer Letters

【 摘 要 】

A synthetic procedure is described for preparation of magneto-sensitive nanocomposites from maghemite nanoparticlesand a natural polysaccharide, sodium alginate cross-linked with calcium ions. With this procedure, a series of nanocompositeswas synthesized and characterized by spectrophotometry, transmission electron microscopy, X-ray diffraction, Mössbauerspectroscopy, Fourier transform IR-spectroscopy and magnetometry with the following main conclusions: (a) Thenanocomposites retain their solubility in water unless the iron content exceeds 18.1±0.2 wt%. (b) Only γ-Fe2O3 nanoparticlesare included in the nanocomposite. (c) Size of nanoparticles lies within a 4–20 nm range with a dominant diameter of 7±1 nm.(d) Maghemite nanoparticles bind to the alginate matrix via formation of electrostatic and coordination contacts betweenthe surface Fe3+ maghemite ions and functional alginate groups. (e) The nanocomposites exhibit properties which are characteristicfor soft magnetic materials since they have a low coercive force. (f) Magnetic characteristics of the nanocomposites,saturation magnetization and residual magnetization, are effectively controlled by the maghemite content. (g) An externalmagnetic field causes the nanocomposites to move in an aqueous dispersion.

【 授权许可】

CC BY