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Biodegradable films based on starches from different botanical sources exhibited physicochemical and functional properties which were related with the starch characteristics. However, had inadequate mechanical properties and were hard and brittle. In this research, jackfruit seed starch plasticized with glycerol were developed and characterized. The starch and glycerol concentrations ranged from 2 to 6% w/w and 20 to 60 g/100 g starch, respectively. Bioplastics were obtained by the casting method and characterized in terms of color, mechanical properties, solubility, water vapor permeability (), morphology and free energy of the hydrophobic interaction. Electronic micrographics showed the presence of some intact starch granules. The bioplastics were hydrophilic and those of 6% starch and 40% glycerol were the most hydrophilic ([Formula: see text] = 41.35 mJ m). The solubility of the films presented a direct relationship with the starch concentration ranging from 16.42 to 23.26%. Increased opacity and color difference were observed with increasing starch concentration. The ranged from 1.374 × 10 to 3.07 × 10 g m/day m which was positively related with the concentration of starch and glycerol. Tensile strength, percent elongation and Young's Modulus indicated that the jackfruit starch and glycerol provided a film with good mechanical properties. The results replaced that jackfruit starch can be used to develop films, with low opacity, moderate and relatively high mechanical stability, by using glycerol in the gelatinized starch dispersions.

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Liquid–liquid equilibrium data of aqueous two phase systems (ATPS) composed of polyethylene glycol (PEG) 1500 g·mol–1 + sodium sulfate + water at T = (293.15, 303.15 and 313.15) K and p = 0.1 MPa were determined. The density of the top and bottom phases of tie-lines (TL) was determined. The universal functional activity coefficient (UNIFAC) model was correlated to the experimental tie-line data, and the root-mean-square deviations (RMSD) between experimental and calculated data were considered in the calculation. The salting-out effect was evaluated using the model of the effective volume (EEV). The temperature had no influence on the binodal curves and TL, this effect can be attributed to a small enthalpic contribution in the phase separation process. Increases in the ATPS constituents concentrations resulting in an increase in the density of the phases. The increase in temperature resulted in an increase in the salting-out effect. The highest estimated value of EEV was obtained for a system at 293.15 K. Calculated RMSD between the experimental and predicted LLE compositions for the PEG 1500 + sodium sulfate systems was 1.71%. The results of the UNIFAC model agree with the experimental tie-line values. The use of this thermodynamic model allowed the acquisition of reliable data for the system, being able to reduce the number of experiments performed.

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