Linear <scp>PEI</scp>-based responsive hydrogels: Synthesis and characterization

Resumen

Abstract Two responsive PEI hydrogels (P1.5E and P2E) were synthesized through a click reaction using linear PEI polymers with different cross-linker contents (ethylene glycol diglycidyl ether-EGDE) and avoiding organic solvents. Through 13 C HRMAS NMR and DSC studies the presence of residual epoxy groups and different protonation states of the linear PEI segments in the hydrogel were detected. The swelling and rheological behavior was dependent on the cross-linking degree. The hydrogel with the lower cross-linking degree (P1.5E) presented higher swelling values, but it was less resistant to the deformation. Besides, the swelling capacity and the resistance to deformation were found to be dependent on the interchain repulsions and charge of the amine groups, which endowed the hydrogels with stimuli-responsive behavior to pH or ionic strength changes. For both hydrogels, the swelling capacity and rheological properties were inversely proportional and directly proportional to the pH increase, respectively. Both materials presented adsorption capacity for the azo dye methyl orange (MO) and Cu 2+ ions. The interaction of the materials with the pollutants was also dependent on the cross-linking degree, being P1.5E the one that presented higher sorption capacities. Furthermore, the hydrogels did not release toxic molecules, as assessed by lettuce seeds germination experiments.

Luis Araque

Investigador en formación

Mis investigaciones son sobre materiales para aplicaciones de recuperación ambiental.

Jonás J. Pérez Bravo

Posdoct-CONICET

He participado en el desarrollo de biomateriales aplicados a la agroindustria, compósitos nanoestructurados para fotodegradación y/o adsorción de contaminantes.

Guillermo Copello

Investigador

Dedicado a la síntesis y caracterización de nanocompuestos a base de polímeros naturales para el desarrollo de materiales inteligentes funcionales

Juan Manuel Lázaro Martínez

Investigador

Dedicado a la síntesis y caracterización de nanocompuestos a base de polímeros naturales para el desarrollo de materiales inteligentes funcionales