Influence of mechanical pretreatment to isolate cellulose nanocrystals by sulfuric acid hydrolysis
| Autor: | Rilton Alves de Freitas, João Pedro Elias Machado, Caroline Novak Sakakibara, Guilherme Fadel Picheth, Maria Rita Sierakowski, Cleverton Luiz Pirich, Andressa Amado Martin |
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| Rok vydání: | 2018 |
| Předmět: |
02 engineering and technology
Chemical Fractionation Microscopy Atomic Force Biochemistry 03 medical and health sciences chemistry.chemical_compound Crystallinity Hydrolysis Structural Biology Zeta potential Cellulose Molecular Biology 030304 developmental biology 0303 health sciences Colloid mill Viscosity Spectrum Analysis Sulfuric acid General Medicine Sulfuric Acids 021001 nanoscience & nanotechnology chemistry Yield (chemistry) Nanoparticles Acid hydrolysis 0210 nano-technology Nuclear chemistry |
| Zdroj: | International journal of biological macromolecules. 130 |
| ISSN: | 1879-0003 |
| Popis: | The mechanical pretreatments intensities on characteristics of cellulose nanocrystals (CNC) prior to acid hydrolysis was evaluated. The cellulose was submitted to mechanical pretreatment as: magnetic stirring (CNCst), blending (CNCbl) or grinding by 20 (CNC20x) and 40 (CNC40x) passages in a super mass colloid mill. Then, all samples were submitted to H2SO4 hydrolysis and the CNC were evaluated by total mass yield (TMY%), rheological behavior, size distribution for width/length (WD), crystallinity index (CI%), OSO3− substitution degree (SD) and zeta potential (ζ). After hydrolysis samples exhibited the same SD (190 ± 5 mMol·kg−1), ζ (−55 ± 3 mV) and CI% (65 ± 2), differing only in TMY% and WD. The CNCst showed TMY% of 85%, WD of 8 ± 5 nm and 100–800 nm, with presence of cellulose nanofibers (CNF), suggesting incomplete hydrolysis. The CNCbl and CNC20x revealed TMY% of 65 ± 1, but differed in WD of 8 ± 5 nm and 300 ± 200 nm and 8 ± 5 nm and 200 ± 170 nm, respectively. The results showed that the grinding mechanical pretreatment is mandatory for CNF isolation, but not for CNC. Stability profile after the hydrolytic procedure, CI%, morphology and similar character generated CNC with adequate features and good yield, by simple mechanical stirring or blending, reducing the production's cost and allowing industrial-scale production. |
| Databáze: | OpenAIRE |
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