Publications by authors named "Davi Rabelo de Oliveira"

Lignin acetylation, one of the most widespread chemical modifications used for improve the solubility of this biopolymer in organic solvents and increase polymer-lignin compatibility, has been performed for decades using time-consuming methodologies and acetylating agents with serious drawbacks. Moreover, traditional acetylation reactions generally conduce to non-selective acetylation of both aliphatic and phenolic groups. In this work, we demonstrated that partial and selective acetylation of kraft lignin can be carried out through a greener, simple and fast microwave-assisted process using acetic acid as solvent and acetylating agent.

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Lignin is a high added-value product obtained from agrowastes through organosolv process to yield materials for technological applications. Here, coconut shell organosolv lignin was fractionated using green solvents (acetone and ethanol) and incorporated in poly(methyl methacrylate) (PMMA) films. The non-fractionated (WCSAL) and soluble fractions (ACT-F and EtOH-F) were completely characterized regarding their structures.

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Pressed palm oil mesocarp fibers (PPOMF) are by-products from oil palm industry and represents a potential source of lignocellulosic biomass. In order to add value to this agro-waste, dewaxed palm oil acetosolv lignin (DPOAL) was extracted under eco-friendly pulping method. The chemical composition and structural characteristics of DPOAL were investigated.

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