Processing optimization of starch-talc nanocomposites by injection moulding at laboratory scale

OTAOLA, FRANCO; LÓPEZ, OLIVIA; CASTILLO, LUCIANA E; GARCÍA, MARIA ALEJANDRA; VILLAR, MARCELO; BARBOSA, SILVIA ELENA

Buenos Aires

Conferencia; 6th International Conference on Science and Technology of Composite Materials (COMAT 2015); 2015

UBA

The aim of this work is to optimize formulations, as well as, processing conditions by injection moulding of composite materials based on thermoplastic starch and talc nanoparticles. An experimental design for mixtures of four components (native corn starch, glycerol, water and talc) was carried out. Mixtures were processed by injection moulding in a mini-mixer. Operational conditions (temperature, rotor speed and time) were optimized, being the most appropriated 150 ºC, 100 rpm and 30 min. All specimens resulted homogeneous without bubbles presence, showing a well talc particles distribution within the matrix and a good interfacial adhesion. Talc presence in composites was evidenced by FTIR through the occurrence of the typical absorption bands of this mineral. Rheological behaviour of injected specimens was evaluated by frequency sweeps, determining elastic and storage modulus, as well as, apparent viscosity. Composites presented a viscoelastic flow characteristic of gel-like materials. Talc increased apparent viscosity of TPS gels.