Isolation and modification of acemannan biopolymer for application in drag reduction
Name: ISAAC DOS SANTOS ORGINO
Publication date: 31/03/2026
Examining board:
Name |
Role |
|---|---|
| CLEOCIR JOSE DALMASCHIO | Presidente |
| EDSON JOSE SOARES | Coorientador |
| IVANOR MARTINS DA SILVA | Examinador Externo |
| RODRIGO REZENDE KITAGAWA | Examinador Interno |
Summary: Drag reduction (DR) by adding polymers is an efficient strategy to minimize energy losses in turbulent flows, being widely applied in fluid transport in pipelines. However, synthetic polymers conventionally used as drag-reducing agents have environmental limitations related to their petrochemical origin and low biodegradability. In this context, biopolymers emerge as sustainable and promising alternatives. This study aimed to isolate, chemically modify, and evaluate the biopolymer acemannan, extracted from Aloe vera mucilage, as a potential DRA in aqueous and organic medium. ACM was isolated by alcoholic precipitation and characterized by FTIR, solid-state NMR, and thermal analyses, confirming its polysaccharide structure and the insertion of acetyl groups after chemical modification. Drag reduction tests were conducted in a Taylor Couette rheometer. The results confirmed the isolation of acemannan with a molecular mass of 1.2 x 106 g/mol and the preservation of the structure after acetylation. In aqueous drag reduction assays, a clear dependence of efficiency on molecular weight was observed, with higher molecular weight fractions showing the highest drag reduction values, around 20 to 22% at 100 ppm, exhibiting stable behavior over time. In organic medium, acetylated acemannan had an estimated molecular weight of 1.6 x 106 g/mol and demonstrated efficiency, with drag reduction reaching approximately 18% at 100 ppm, as well as good stability over time, indicating that the chemical modification did not compromise the structural integrity of the polymer and was effective in adjusting its polarity for application in non-polar systems. The results consolidate acemannan as a promising biopolymer for drag reduction, both in aqueous medium and, after chemical modification, in organic systems.
