Influence of the plasticizer on rice bran-based eco-friendly bioplastics obtained by injection moulding

The manufacture of eco-friendly bioplastic materials from renewable resources to replace petroleum-based plastics has attracted increasing attention. For many years, proteins, lipids and polysaccharides have been proposed as natural biopolymers sources to obtain biodegradable plastic materials. As b...

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Detalles Bibliográficos
Autores: Alonso González, María, Félix Ángel, Manuel, Romero García, Alberto
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/131298
Acceso en línea:https://hdl.handle.net/11441/131298
https://doi.org/10.1016/j.indcrop.2022.114767
Access Level:acceso abierto
Palabra clave:Bioplastics
Rice bran
Sustainability
Plasticizer
Injection moulding
Descripción
Sumario:The manufacture of eco-friendly bioplastic materials from renewable resources to replace petroleum-based plastics has attracted increasing attention. For many years, proteins, lipids and polysaccharides have been proposed as natural biopolymers sources to obtain biodegradable plastic materials. As by-product from the rice industry, rice bran, is an available and non-expensive resource of both proteins and starches, food groups that, properly processed, can be employed in the development of bioplastics. Plasticizers are essential for the manufacture of bioplastics and, when carbohydrate/protein mixtures are used, an adequate selection of plasticizers must be addressed. By these means, a material suitable for thermo-mechanical processing methods is obtained if starches are subjected to shear forces under high temperatures and water excess (gelatinisation). Moreover, additional polyol-based plasticizers, such as glycerol and sorbitol, allow obtaining reinforced products with improved elasticity when protein-based bioplastics are processed. The aim of the present study was to analyse the plasticizing effect of water combined with different proportions of glycerol or sorbitol, as well as their influence on the final bioplastic properties. Results indicate that higher water ratios produce stiffer bioplastics with improved viscoelastic moduli, maximum stress and Young´s modulus, while increasing the glycerol and sorbitol content leads to higher elasticities and water uptake capacities in general. Moreover, sorbitol seems to provide more suitable bioplastics with better tensile (up to 500% in Young´s modulus) and functional properties compared to glycerol.