For the purpose of the development of poly(lactic acid)/ graphene oxide composites with improved tensile properties, a stearic acid compatibilizer was used to enhance the compatibility of the graphene oxide sheets with the poly(lactic acid) polymer matrix. Graphene oxide was modified with stearic acid at different mass ratios of 1:1, 1:3, and 1:5 prior to forming the composites with poly(lactic acid). Characterization showed positive effects of stearic acid attached to GO in every mass ratio and also enhanced compatibility with the poly(lactic acid) matrix. Stearic acid could strengthen the interfacial interactions between the flat graphene oxide sheets and the poly(lactic acid) matrix resulting in improved tensile strength. The tensile strength of the poly(lactic acid)/graphene oxide/ stearic acid composite with a mass ratio of graphene oxide and stearic acid 1:1 increased by 32% compared to poly(lactic acid) alone. Based on these results, the graphene oxide/stearic acid composites show potential for use as nanosheet fillers for tensile strength enhancement in poly(lactic acid). POLYM. COMPOS., 38:2272-2282, 2017

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Barley straw is a lignocellulose agricultural waste material that can be utilized as a raw material for ethanol production since it is easy to find, cheap, and has the potential to produce ethanol yield. This research aims to select the optimum pretreatment conditions to increase fermentable sugar production during enzymatic hydrolysis for bioethanol production. Initially, sulfuric acid at a concentration of 0.5, 1.0, 1.5, and 2.0% (v/v) pre-treated barley straw biomass was applied by autoclaving at 121℃ for 15 lb/in2 pressure for 15 min. Furthermore, acid-treated barley straw under the alkaline condition with calcium hydroxide concentrations of 1, 2, 3, and 4% (w/v) was autoclaved at 121℃ for 15 lb/in2 pressure for 15 min. Subsequently, the pretreatment of barley straw in the acetic and alkaline processes was compared. It was found that calcium hydroxide at a concentration of 2% (w/v) gave more sugar concentrations. Finally, combined acid and alkaline pretreatment with 2% of cellulase enzymatic hydrolysis had the highest total sugar concentration of 205.43 g/L and reducing sugar of 134.42 g/L, producing the highest ethanol yield (16.17 g/L) by 24 hours of fermentation.

This study aimed to produce a nanocatalysts from inexpensive barley straw using nickel (Ni) and cobalt (Co) to support waste cooking oil-based biodiesel production. At 400 °C without oxygen and 1-5 bars of pressure, the gasification procedure of barley straw biomass (100g dry basis) was utilized in a muffle furnace with Ni and Co nano-catalysts. The biomass:Ni:Co catalyst mixing ratio is 1:1:1. The catalyst content and reaction time were applied for 2 hours. Then, at molar ratios of methanol:oil (6:1, 9:1, and 12:1) with the amount of catalyst (1, 2, and 3% weight percent basis), at 2 hours reaction time. Accordingly, the factors impacting the transesterification of biodiesel synthesis were evaluated. The process employing methanol:oil molar ratio of 6:1 and a catalyst quantity of 2% wt was the best for producing biodiesel. Based on the results of this study, nanocatalysts formed from biomass, which can be obtained from agricultural waste, hold commercial promise as a catalyst source for biodiesel.

This research aims to develop films from natural materials to be used as seasoning packaging for instant noodles. Natural materials such as bananas and konjac are used as raw materials for film-forming. There were 27 formulations of film-forming, including 9 formulas from the banana starch film, 9 formulas from banana starch blended with konjac powder 0.5% w/w, and 9 formulas from banana starch blended with konjac powder 1.0% w/w. The mechanical and physical properties of various formulation films were tested. When selecting a formulation film that meets the packaging requirements for 2 formulations by selecting one banana starch film and one banana starch film blended with konjac powder, it was found that the film formula B4Gly20 (banana 4 % W/V and glycerol 20 % V/V) and formula K05/4Gly20 (konjac 0.5 % W/V blended with banana 4 % W/V and Glycerol 20 % V/V) have the best fit. They had properties close to specifications such as thickness and water permeability, not significantly different at 0.05%, and high tensile strength of 4.015 and 5.172 N/mm2. The flexibility was 27.67 and 22.22 percent, and the water vapor permeability was 0.0063 and 0.0021 g/hr.cm2, respectively., resistance to acidic solutions, and can be formed into strong packaging film, etc. When applying these two film formulas to the seasoning packaging of instant noodles, it was found that both film formulations did not prevent moisture in the air. The film formula B4Gly20 effectively prevented oil leakage. And also, B4Gly20 was more resistant to oxygen penetration into the cooking oil than K05/4Gly20 formulation film, but film formulation B4Gly20 was dissolved in hot water 100 ± 10 °C slower than K05/4Gly20. The results showed that the film formulation B4Gly20 was suitable for application in the seasoning packaging of instant noodles.