Desarrollo de hidrogeles como actuadores para el control de humedad en suelo

WOLFEL, ALEXIS; ROMERO MARCELO; C.I. ALVAREZ IGARZABAL

Santa Fe

Congreso; Congreso Internacional de Metalurgia y Materiales SAM-CONAMET/ IBEROMAT 2014; 2014

Chemical actuators are devices that use chemical energy from its environment to transform it into a mechanical response. Hydrogels can swell in response to chemical or physical changes in their surroundings therefore, they were used for the development of different actuator types such as valves, pumps and mixers. However, the hydrogel composition must be carefully selected and studied because only some materials have the ability to change its volume producing a lot of force and reversible swelling / deswelling cycles. Due to the ability of hydrogels to swell in contact with water, we have assessed its application as valves used to control soil moisture. Therefore, in this work were prepared hydrogels with optimal properties to move a mechanical system to monitor soil moisture. Hydrogels synthesized with acrylamide as the main monomer showed the best rheological properties, swelling between 200-500%, normal force greater than 40N (using a disc of 1cm2) and adequate reversibility. Furthermore, 50% of swelling was reached in 1.5 h and 95% in 5h. The hydrogels were tested in soil with different humidity and they reached a volume of equilibrium directly proportional to the amount of soil moisture. Subsequently, a valve using a small disc of hydrogel to control the flow of water was developed and the dynamics of the system was registered with an optical system associated to an analog to digital converter.