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A bioplastic semirrigid material was developed from native flour of four cassava varieties (MBRA 383, MPER 183, CM 4574-7 and CM 7951-5), incorporating fique dust, by thermo-compression technique. The material was obtained by subjecting the raw material mixture in a mold and subsequently it was compressed at 200°C. The cassava variety suitable for use in the material development was MPER 183, with results of last tensile and flexural resistance of 1,8 MPa ± 0,2 and 3,5 ± 0,2 MPa, respectively, and resistance to impact of 21,2 ± 0,1 J/m. Compression molded samples, obtained in this work are technologically feasible and favorable performance characteristics presented as an alternative to the use of polystyrene foam food packaging applied. [ABSTRACT FROM AUTHOR]

Starch is a renewable and cheap natural polysaccharide from that is easily to make biodegradable plastic products. However, its products have low mechanical properties and tend to change its properties in the presence of water. For reduce the problems caused for water in the plastic product derived from starch, originate from de high hydrophilicity of this polymer, are diverse strategies such as the chemical modification of starch, the blend of starch with minor hydrophilic polymers and the superficial modification of the final products. In the present review is presented some examples of investigations related with the mentioned strategies, focused the attention in superficial modification that allow decrease the hydrophilicity of plastic products based on starch without affect the internal characterizes of material significantly. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of different oxidation conditions by hypochlorite, on the content of carboxyl and carbonyl groups of cassava starch, finding that the concentration of oxidant had the highest effect on the formation of both groups functional. The pH had a highest effect on the content of carbonyl groups than on the content of carboxyl groups. Likewise, oxidized starch was obtained at three degrees of oxidation which exhibited lower viscosity, higher gel stability and lower retrogradation tendency when compared with native starch. Films were obtained and their mechanical and thermal properties were evaluated, finding that higher modification degree incremented stress while the strain exhibited no significant differences. Conversely, the greater modification degree, the films showed lower strain and the stress showed no significant differences. The thermal analysis showed a Tg, which is not present in native starch films, a higher Tm and a gradual decrease of ΔHm with oxidation degree increasing, which might suggest a greater miscibility and interaction between film components as well as greater stability. [ABSTRACT FROM AUTHOR]