CONICET | Buscador de Institutos y Recursos Humanos

This work was design as a possible response to growing pollution caused by plastics derived from petroleum with long degradation times. The use of polymers capable of being degraded by the action of microorganisms and/or enzymes which have no harmful effect is a strategy that has introduced a new concept in waste management [1]. These new polymers are used primarily as food packaging, but most of them do not have the appropriate properties for these applications therefore one possible solution is to prepare blends of a traditional polymer and other biodegradable looking for aceptable mechanical properties and shorter degradation times. In this work blends of polystyrene (PS)/thermoplastic starch (TPS from cassava starch) and PS/MaterBiK at different proportions from 90:10 to 50:50 (w:w) were prepared by casting and melt blending. The PS/TPS blends were characterized by Scanning Electron Microscopy (SEM); Thermo Gravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), tensile tests and biodegradation in soil. The degradation was also followed by TGA and FTIR. SEM results showed a good dispersion of the starch in the blends. The displacement of some FTIR and TGA characteristic peaks suggested that not only physical but also chemical interactions between the PS and the TPS took place in the blends [2]. Tensile tests revealed a considerable decrease in mechanical properties of the PS-TPS mixtures with respect of pure PS. The results of the biodegradability tests showed that the greater the proportion of TPS in the mixture, the greater the mass loss, which was also confirmed by TGA and FTIR analysis performed on degraded samples. The fracture characterization was performed to PS/MaterBiK samples. The results shown the improvement of the fracture parameters of MaterbiK by blending it with 30wt.% of PS.