Resumo

CORTES, JOSÉ FELIPE; FERNANDEZ, AMANDA LUCÍA; MOSQUERA, SILVIO ANDRÉS  e  VELASCO, REINALDO. ASSESSMENT OF MECHANICAL, OPTICAL AND BARRIER PROPERTIES IN ACTIVE FILMS FROM CASSAVA STARCH. Rev.Bio.Agro [online]. 2014, vol.12, n.1, pp.88-97. ISSN 1692-3561.

Films obtained from cassava starch variety CM 7138-7, native and modified by hydroxypropylation were subjected to mechanical evaluations, optical and barrier during periods of 0, 30, 60, 90 and 120 days by determining the effect of storage time on the chemical modification. The films were obtained by extrusion blowing using a single screw extruder. The material was obtained in three stages: the first stage was the production of Thermoplastic Starch (TPS) with 75% starch, 24,5% glycerol and 0,5% capsaicin; in the second step the Binary Mixture (MB) was made with 68,63 % of Polylactic Acid (PLA), 29,41% of Polycaprolactone (PCL), 1,96 % of maleic anhydride and 1 % of dye, and finally the blown extrusion of the ternary mixture, consisting of 75% of TPS and 25% of MB. Changes of some properties with time, were more evident in the films based on native starch, with significant difference, due to retrogradation process and possibly to a homogeneous phase in the material is not formed and therefore the components were divided into separate and distinct phases .

Palavras-chave : Hydroxipropilation; Starch; Extrusion; Effort; Permeability.

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