Acetylation of bacterial cellulose catalyzed by citric acid: Use of reaction conditions for tailoring the esterification extent

• Published in: Carbohydrate polymers Vol. 153; pp. 686 - 695
• Main Authors: Ávila Ramírez, Jhon Alejandro, Gómez Hoyos, Catalina, Arroyo, Silvana, Cerrutti, Patricia, Foresti, María Laura
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 20-11-2016
• Subjects: Acetylation; Bacterial cellulose; Catalysis; Cellulose - analogs & derivatives; Cellulose - ultrastructure; Citric acid; Citric Acid - chemistry; Esterification; Gluconacetobacter xylinus - chemistry; Polysaccharides, Bacterial - analogs & derivatives; Polysaccharides, Bacterial - ultrastructure; Reaction conditions; Bacterial cellulose; Acetylation; Reaction conditions; Citric acid
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2016.08.009

•BC nanoribbons were partially acetylated by a simple route catalyzed by citric acid.•Reaction variables can be manipulated to acetylate BC to the required DS.•Surface-only acetylated BC with increased hydrophobicity could be easily obtained.
Bacterial cellulose (BC) nanoribbons were partially acetylated by a simple direct solvent-free route catalyzed by citric acid. The assay of reaction conditions within chosen intervals (i.e. esterification time (0.5–7h), catalyst content (0.08–1.01mmol/mmol AGU), and temperature (90–140°C)), illustrated the flexibility of the methodology proposed, with reaction variables which can be conveniently manipulated to acetylate BC to the required degree of substitution (DS) within the 0.20–0.73 interval. Within this DS interval, characterization results indicated a surface-only process in which acetylated bacterial cellulose with tunable DS, preserved fibrous structure and increased hydrophobicity could be easily obtained. The feasibility of reusing the catalyst/excess acylant in view of potential scale-up was also illustrated.