Abstract

GONZALEZ, Neudys et al. Study of the diffusion kinetics in hydrogels synthesized from acrylamide-co-acrylic acid with pet and starch by conventional heating and radiation microwaves. Rev. LatinAm. Metal. Mater. [online]. 2012, vol.32, n.1, pp.136-144. ISSN 0255-6952.

In this work of investigation polymers were synthesized hydrogels from acrylamide (AAm), acid acrylic (AAc), peat and starch, by means of conventional heating and low radiation microwaves. Hydrogels hydration (swelling) kinetic parameters were determined using different models (Schott, Fick). The results obtained reflected that AAm-co-AAc/starch (F2) hydrogels synthesized of conventional way presented majors values of water content (m∞) 94,34%, in comparison with synthesized in microwaves AAm-co-AAc/starch (F2M) that display values of m∞ 84,75%. On the other hand, the obtained results of the diffusion study reflected that hydrogels copolymers conventional showed a diffusion behaviour of the anomalous type. Whereas in the semi-IPN hydrogels, the presence of starch and peat transfer the n from 0,87 to n lower (between 0,4 and 0,5), controlled by a Fickian diffusion. Hydrogeles synthesized in the same conditions by microwaves, showed n smaller (between 0,3 and 0,4), because penetration rate is much below the polymer chain relaxation rate.

Keywords : hydrogels; polymers; microwaves; diffusion.