Preparation and characterization of thermoplastic starch at pilot plant scale

M.P. GUARÁS; L.N. LUDUEÑA; V.A. ALVAREZ

Santa Fé, Argentina

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

In this work, a formulation of thermoplastic starch (starch, plasticizer and additives) optimized in previous studies, was selected. It was used, a ratio of 69.5/30/0.5% by weight of corn starch/glycerol/stearic acid. The materials will be blended in a twin-screw extruder D=18 mm and L/D = 25D with speed and temperature of 50rpm and 160°C, respectively. Native starch was introduced into the main hopper and the plasticizer was incorporated (with the stearic acid predissolved therein) via a peristaltic pump to maintain the correct dosage of fluid during continuous extrusion. After the extrusion process, the material was pelletized and films were prepared by compression molding for further characterization. The thermal properties (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)), mechanical properties (universal testing machine) and rheological properties (oscillatory rheometry with parallel plates configuration) of the obtained films were characterized.