title: Thermo-mechanical and hydrophilic properties of polysaccharide/gluten-based bioplastics.
abstract: The influence of adding different polysaccharides (locust bean gum, LBG; methyl cellulose, MC; and carboxymethyl cellulose, CMC) to gluten-based biodegradable polymeric materials was assessed in this work. Gluten/polysaccharide/plasticiser bioplastics were prepared at different polysaccharide concentrations (0-4.5%) and pH values by mixing in a two-blade counter-rotating batch mixer (at 25 °C under adiabatic conditions) and thermomoulding at 9MPa and 130 °C. Bioplastic probes were evaluated through dynamic mechanical thermal analysis, tensile strength and water absorption capacity tests. Results pointed out that a moderate enhancement of the network structure may be achieved by adding polysaccharide at a pH close to the protein isoelectric point (pH 6), which also conferred a further thermosetting capacity to the system. Moreover, the addition of MC and CMC was found to significantly enhance material elongation properties. However, the presence of charges induced by pH leaded to a higher incompatibility between the polysaccharide and protein domains forming the composite. The pH value played a relevant role in the material water absorption, which significantly increased under acidic or basic conditions (particularly at pH 3).
authors.affiliation: Universidad Pedagógica y Tecnologica de Colombia UPTC, Facultad de Ingeniería, Escuela de Metalurgia, Avenida Central del Norte, Tunja, Colombia.
authors.forename: L S
authors.initials: LS
authors.lastname: Zárate-Ramírez
authors.affiliation: Departamento de Ingeniería Química, Universidad de Sevilla, Escuela Politécnica Superior, 41011 Sevilla, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Romero
authors.affiliation: Departamento de Ingeniería Química, Universidad de Sevilla, Escuela Politécnica Superior, 41011 Sevilla, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Bengoechea
authors.affiliation: Departamento de Ingeniería Química, Centro de Investigación en Tecnología de Productos y Procesos Químicos (Pro(2)TecS) - Campus de Excelencia Internacional Agroalimentario, ceiA3, Universidad de Huelva, Campus el Carmen, 21071 Huelva, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Partal
authors.affiliation: Departamento de Ingeniería Química, Universidad de Sevilla, Escuela Politécnica Superior, 41011 Sevilla, Spain. Electronic address: aguerrero@us.es.
authors.forename: A
authors.initials: A
authors.lastname: Guerrero
mesh_terms: D063566:Biodegradable Plastics / Q000737:chemistry*; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D005685:Galactans / Q000737:chemistry; D005983:Glutens / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008351:Mannans / Q000737:chemistry; D008747:Methylcellulose / Q000737:chemistry; D053149:Plant Gums / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D013718:Tensile Strength; D014867:Water / Q000737:chemistry
chemical_list: D063566:Biodegradable Plastics; D005685:Galactans; D008351:Mannans; D053149:Plant Gums; D011134:Polysaccharides; D014867:Water; D005983:Glutens; D008747:Methylcellulose; D002266:Carboxymethylcellulose Sodium; C017471:locust bean gum
keywords: Bioplastics; Dynamic mechanical thermal analysis; Polysaccharide; Tensile strength tests; Water absorption capacity; Wheat gluten