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In this study, sugar palm crystalline nanocellulose (SPCNC)-reinforced thermoplastic sugar palm starch (TPS) was blended with poly(lactic acid) (PLA) in order to prioritize the biodegradation feature while offsetting individual polymer limitation. Prior to melt blending process, SPCNC was dispersed through sonication in advance of starch gelatinization which was later casted into petri dishes. PLA and TPS were melt blended into five different ratios using Brabender mixer followed by compression molding. Soil degradation (4 months) and water uptake (4 weeks) tests were conducted to evaluate the physical stability of PLA/TPS blend bionanocomposites. Based on Fickian law, the diffusion curve and coefficient of diffusion for seawater, river water, and sewer water were calculated. The flammability and limiting oxygen index (LOI) tests were conducted in accordance with ASTM D635 and ASTM D2863, respectively. For PLA60TPS40 (40% TPS), significant reduction (46–69%) was recorded in maximum water uptake in all mediums, while soil degradation rate experienced insignificant increment (7.92%) for PLA70TPS30 (30% TPS) owing to the reinforcement of SPCNC through the well-dispersed TPS within PLA. Meanwhile, the flammability rates and LOI values for PLA40TPS60 and PLA60TPS40 indicated flammable material properties.

In this study, papaya (Carica papaya) peel was dried using convection oven and microwave drying methods to investigate the drying kinetics and the drying behavior in the attempt to search for a feasible way to utilize waste peel. Three different drying temperatures (45, 55, and 65 °C) and microwave powers (250, 440, and 600 W) were applied to dry the papaya peel, wherein the drying data were fitted into the following seven drying kinetic models: Lewis, Page, Modified Page, Henderson and Pabis, Logarithmic, Two-Term, and Approximation of Diffusion models. The study outcomes indicated that the Page model emerged as the best fitted model for oven drying of papaya peels with the highest coefficient of determination (R²) value (0.994-0.996) for all the three temperatures. As for microwave drying, the Approximation of Diffusion model exhibited the best fit owing to the highest R² value (0.996-0.999) for all the three powers. The effective moisture diffusivity values for convection oven and microwave drying methods ranged from 6.65 x 10-08 to 4.35 x 10-07 and from 2.43 x 10-07 to 6.67 x 10-07, respectively. Additionally, the activation energy values were recorded at 61.301 kJ/mol and 46.621 W/g for oven and microwave drying methods, respectively. [ABSTRACT FROM AUTHOR]