Valorización de la oca (Oxalis tuberosa) para la obtención de mezclas biopoliméricas

Abstract

The present investigation aims is to evaluate the oca (Oxalis tuberosa) in order to obtain biopolymer blends, from carbohydrate derived from goose, poly(lactic acid) (PLA), glycerol, and polyvinyl alcohol (PVA). Initially, the carbohydrate was obtained, and subsequently the blends were formulated on the basis of a mixed factorial experimental design 3 x 3 x 2. Different proportions of PLA (35, 37 and 40%), PVA (3, 6 and 9.0%), and starch: glycerol (A: G) (45:55 and 50:50) were used. The raw materials were processed in a rheometer for 25 min at 120°C and 100 rpm. The product of the last process was compressed at 17 MPa for 5 min at 120°C in a heated press. The mechanical characterization of the biopolymer sheets was performed by tensile-strain tests. This characterization allowed to determine that the tensile strength and elongation at fracture increased as the percentage of PLA increased to 40%, PVA to 9%, and with an A:G relationship of 50:50. The study of thermal behavior by differential scanning calorimetry (DSC) evidenced the presence of a single glass transition temperature (Tg), which reflected the interaction of the components.