In this work, sugarcane bagasse fiber, a waste product of agroindustry, was added to mortar mixes at different proportions looking to seal porosities so as to improve the resistance of concrete to carbonation and to improve its mechanical properties. To evaluate the behavior of bagasse fibers in the alkaline media typical of mortars, bagasse fibers were subjected to solutions with alkaline pH values, and their chemical structure and morphological behavior was evaluated using FTIR (Fourier transform infrared spectroscopy) and SEM (Scanning Electron Microscopy). Using mortar cylinders in an accelerated carbonation chamber to obtain results in short lapses, the compressive strength and the carbonation were evaluated. The FTIR analysis results indicate that pH values of 11 and 12 causes a delignification, while at pH 9 and 10, a swelling of the molecule occurs because of the addition of hydroxyl ions, behavior that is confirmed with SEM images. A clear effect of the fiber addition on the performance of concrete was observed as the carbonation front of 35 mm for the sample without fibers was reduced to 2 mm for the sample with 2% fiber addition, resulting in an increase of 5 MPa in compressive strength. These results indicate that in the range of mortar pH, chemical changes occured over the sugarcane surface that could cause the growth of fibers and could partially seal the porosity in the mortars, thus enhancing its performance.

This work shows the performance of cathodic protection systems formed by an API (American Petroleum Institute) X52 steel exposed to seawater and coupled with galvanic anodes of Mg, Mg-1Cr, and Mg-1Nb fabricate by sintering technique at a temperature of 500 °C. Potential monitoring indicates that X52 steel of the three systems remained in the protection zone. Mg-Nb/X52 system showed the more stable potentials since the first day; the recorded values remained between −1.0 and −1.1 V vs. SCE (saturated calomel electrode) during the seven days of exposure time. Current density records show that Mg/X52 system had the most stable values, while the other two systems (Mg-Cr/X52 Mg-Nb/X52,) had current fluctuations. The Mg-X52 system recorded the most negative potential values, which can be attributed to a greater magnitude and a better distribution of the cathodic protection current. However, the Mg-Nb/X52 system had a better result because the current drained by the system was constant throughout the experiment.

The development of biodegradable materials arises as an alternative to reduce the pollution caused by plastic waste to the environment, with this premise this study was proposed to develop plastic biopolymers from bioactive compounds with different matrices modified cassava starch (5 – 12 %), fish scale collagen (10 – 40 %), lemon essential oil (0,5 - 1,5 %) and gelatinization temperature (70 – 80 °C); A Box Behnken response surface experimental design was used; with the determination of their mechanical properties (maximum stress, Young's modulus, shear strength, stress at break and percentage elongation at break). According to the results found, it was determined that the modified cassava starch had the greatest influence on the mechanical properties, taking into account its importance to create more resistant materials, but it evidences plasticizing difficulties, where the fish scale collagen has a significant influence. In addition, it is evidenced that lemon essential oil had a great influence on Young's modulus (46,28 ± 2,31 MPa) and the percentage of elongation (69,69 ± 2,16 %); while the gelatinization temperature of 80 °C is not recommended for this type of starch-protein matrices due to damage of the structure; determining a better mechanical resistance and a great increase of Young's modulus. In conclusion, the characteristics and performance of the film based on cassava starch, collagen flakes and lemon essential oil have a positive impact on the maximum level of mechanical efficiency of the biodegradable films, achieving a better performance in their mechanical properties. La elaboración de materiales biodegradables surge como alternativa para disminuir la contaminación causada por los desechos plásticos al medio ambiente, con esta premisa, se propuso este estudio comprendido en el desarrollo de biopolímeros plásticos, a partir de compuestos bioactivos con diferentes matrices de almidón modificado de yuca (5 – 12 %), colágeno de escamas de pescado (10 – 40 %), aceite esencial de limón (0,5 - 1,5 %) y temperatura de gelatinización (70 – 80 °C). Se utilizó un diseño experimental de superficie de respuesta Box Behnken; con la determinación de sus propiedades mecánicas (esfuerzo máximo, módulo de Young, fuerza de corte, esfuerzo a la ruptura y porcentaje de elongación de ruptura). Según los resultados encontrados, se determinó que el almidón modificado de yuca fue el de mayor influencia en las propiedades mecánicas, teniendo en cuenta su importancia para crear materiales más resistentes, pero evidencia dificultades plastificantes, donde el colágeno de escamas de pescado incide significativamente. Además, se evidencia que el aceite esencial de limón presentó gran influencia en el módulo de Young (46,28 ± 2,31 MPa), y en el porcentaje de elongación (69,69 ± 2,16 %); mientras que la temperatura de gelatinización de 80 °C no es recomendada para este tipo de matrices almidón - proteína por daños de la estructura; determinando una mejor resistencia mecánica y un gran aumento del módulo de Young. En conclusión, las características y el rendimiento de la película a base de almidón de yuca, colágeno de escamas, y aceite esencial de limón; tienen un impacto al considerar el nivel máximo de eficacia mecánica de películas biodegradables y alcanzar un mejor comportamiento en sus propiedades mecánicas.