Mechanical properties of trays based on starch of native plant species and fiber of agroindustrial wastes

Abstract

ResumenEl objetivo de este trabajo fue evaluar el efecto de las fibras naturales obtenidas de residuos agroindustriales en la densidad, el gramaje y las propiedades mecánicas de las espumas termoprensadas elaboradas de almidón de especies nativas, como lo son el camote, la oca y la arracacha. El proceso de termoformado se llevó a cabo a una temperatura de 145 °C y una presión de 60 bar. El tiempo de horneado fue de 10-15 min dependiendo del contenido de agua en la mezcla. Las bandejas fueron caracterizadas por su densidad, gramaje, ensayo de impacto, ensayos de deflexión, colorimetría y sus valores de dureza y fracturabilidad. Las bandejas elaboradas por termopresión a base de almidón de camote-fibra de bagazo de caña de azúcar al 15%, y de almidón de arracacha-fibra peladilla de espárrago al 30% presentaron mayores valores en resistencia a la flexión frente a las elaboradas con otros tipos de almidones y fibras, incluyendo a pruebas en blanco. De manera general, la dureza de las bandejas se ve favorecida con el incremento de fibra, sin embargo, la fracturabilidad decrece o no mejora la integridad de la matriz polimérica. Los resultados mostrados en esta investigación permitirán la elaboración de bandejas biodegradables para distintas aplicaciones industriales.Palabras clave: biodegradable; espumas termoprensadas; almidón de camote, oca y arracacha; fibra de bagazo y peladilla; propiedades mecánicas. AbstractThe aim of this study was to evaluate the effect of natural fibers derived from agro-industrial waste in density, weight and mechanical properties of the termoprensadas foams made of starch native species, such as sweet potatoes, oca and arracacha. The thermoforming process was carried out at a temperature of 145 ° C and a pressure of 60 bar. The baking time was 10-15 min depending on water content in the mixture. The trays were characterized by their density, weight, impact test, deflection tests, colorimetry, hardness, and fracturability values. The trays prepared by thermopressure based on sweet potato starch-bagasse fiber from sugar cane at 15%, and arracacha starch -peladilla asparagus fiber at 30% had higher values in flexural strength versus those made with other types of starches and fibers, including blank tests. Generally, the hardness of the trays is favored with increasing fiber, however fracturability decreases or does not improve the integrity of the polymeric matrix. The results shown in this study allow the preparation of biodegradable trays for various industrial applications.

Pineapple shell fiber as reinforcement in cassava starch foam trays

“…One of the most used is expanded polystyrene (EPS), commercially known in Peru as tecnopor , with which many food packaging products are manufactured, because it is a good thermal insulator, moisture resistant, lightweight, moldable, and inexpensive. 1 However, EPS generates environmental problems related to deterioration of landscapes, air pollution when burned or persistence in the environment due to their resistance to biodegradation. 2…”

“…Starch obtained mainly from cassava, potato, and corn are being used in the production of biodegradable foams. 1,3,4 However, starch-based foams have some weaknesses compared to petroleum-based packaging, related to their poor mechanical properties and hydrophilicity, which hinders its application, and, therefore, it is necessary to study the incorporation of new additives to improve their microstructural, physicochemical, and mechanical properties. 3,4 Additives, such as chitosan, proteins and lignocellulosic fibers, have been used as reinforcing materials to reduce the rigidity and water absorption capacity, improves elongation, and increases the biodegradability of the composites.…”

“…Agro-industrial wastes are emerging as promising substitutes for conventional plastics. 1 Several studies have shown that the use of natural fibers improves the physical and mechanical properties of starch-based packaging, for example, malt bagasse fiber, 1 asparagus peel fiber, 6 sugarcane bagasse fiber, 7 -9 corn fiber, 10,11 and kraft fiber, 12 among others.…”

The addition of sugarcane bagasse and asparagus peel enhances the properties of sweet potato starch foams

“…The third additional event occurred between 360°C and 600°C, with a greater maximum peak almost at 478°C for the composite trays as compared with control tray (408°C), which indicates that the addition of SB or AP fibers increased the thermal stability of the sweet potato starch‐based foam tray. This stage is ascribed to the partially decomposed starch underwent oxidation, to generate solid residues such as ashes and inorganic materials (around 20% of the initial mass) and also may be ascribed to the degradation of lignin, which is present in the SB and PA fibers …”

“…This stage is ascribed to the partially decomposed starch underwent oxidation, to generate solid residues such as ashes and inorganic materials (around 20% of the initial mass) and also may be ascribed to the degradation of lignin, which is present in the SB and PA fibers. 42,47,48 4 | CONCLUSIONS…”