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With the current trend of increasing efforts to develop non-isocyanate-based polyurethanes (NIPUs), this study aimed to check the feasibility of the development of a method using cyclic carbonate modified catechin and amine to synthesis non-isocyanate urethane with the objective to further extend these results to polyurethane synthesis. The methods used in this study consist of four steps: glycidilation of catechin, hydrolysis of epoxide, cyclic carbonate synthesis, and carbamate synthesis through condensation of butylamine. The resulting products were analyzed using FTIR (Fourier transform infrared) spectroscopy and NMR (nuclear magnetic resonance) spectroscopy. The results showed that carbamate could be successfully obtained through this four-steps synthesis, opening the possibility to further developments for the synthesis of polyurethanes starting from catechin and condensed tannins.

This working paper elaborates on the reasons why illegal logging activities still exist in Indonesia despite the efforts that have been made by the government. This paper offers recommendations for tackling the misdeclaration of timber information. It aims to provide recommendations to the Government of Indonesia to strengthen the SVLK's role in ensuring timber legality and enforcing the law by applying science-based technologies as criminal evidence for illegal logging cases.

This study evaluated the methods of grafting commercial catechin with fatty acids, namely capric acid (C10), lauric acid (C12), and myristic acid (C14) through esterification. Specimens of beech wood (Fagus sylvatica L.) were impregnated with catechin and modified catechin-fatty acids, separately, at a 5% concentration diluted in ethanol using vacuum pressure treatment and subjected to leaching. The weight percentage gain before leaching (WPG), after leaching (WPGAL), and weight loss due to leaching (PL) were investigated. Both leached and unleached samples were tested against white-rot fungi (Trametes versicolor) in Petri-dishes for twelve weeks. Results show that samples treated with modified catechin-fatty acids provide improved resistance towards leaching. Catechin-C14 was found to be more promising, possibly due to its chain length. The decay weight loss for samples treated with modified catechin-fatty acids does not differ significantly between the samples that leached and not. Despite the antifungal properties of catechin, the treatment with catechin alone was insufficient to protect wood samples from fungi. Further, it is recommended to increase the concentration level of modified catechin to obtain a significant effect on the decay resistance.