THURSDAY 15:00
CHARACTERIZATION AND SIZE CONTROL OF AGAROSE MAGNETIC MICROFIBERS
Rosita Ormaza
Escuela Politécnica de Chimborazo, Ecuador
ABSTRACT
An experimental study concerning the manufacture of polymeric microfibers with magnetic inclusions is described. We contemplate the control of length and diameter, analysis of the way nanoparticles (NPMs) of maghemite are incorporated in the polymer hydrogel, its spatial distribution and the type of confinement. For this, the emulsion is destabilized in the presence of magnetic fields, between two slide plates, separated by an O-ring that allows to control the dimensions of the fibers. Results were obtained with diameters between 35 and 55 nm, and lengths reaching a ratio of up to 88.55% with the thickness of the O-ring used; the measures showed a maximum deviation of 10%. Through the use of instrumental techniques (TEM, FTIR, SEM), the homogeneous dispersion of maghemite particles in the agarose gel was determined. The presence of covalent bonds was ruled out, but it is believed that the confinement of NPMs in the gel is due to the electrostatic interactions between carboxyl groups of the citrate and oxidryl groups of the agarose. In addition, the fibers presented a tip termination, which predicts high levels of threshold stress of the dispersions prepared based on these microfibers.