| Full text | |
| Author(s): |
Eliangela de M. Teixeira
[1]
;
Cauê R. de Oliveira
[2]
;
Luiz H. C. Mattoso
[3]
;
Ana C. Corrêa
;
Priscila D. Paladin
Total Authors: 5
|
| Affiliation: | [1] Embrapa Instrumentação Agropecuária
[2] Embrapa Instrumentação Agropecuária
[3] Embrapa Instrumentação Agropecuária
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | POLIMEROS-CIENCIA E TECNOLOGIA; v. 20, n. 4, p. 264-268, 2010-11-12. |
| Abstract | |
The thermal stability of cellulose nanofibers is related to their application and especially to polymer processing normally occurring at ca. 200 °C. In this work, nanofibers of commercial cotton were obtained by acid hydrolysis employing different acids: sulfuric, hydrochloric and a mixture (1:1; sulfuric acid: hydrochloric acid).The morphology of the nanofibers were characterized by transmission microscopy (TEM), zeta potential, elemental analysis, crystallinity by X ray diffraction (XRD) and thermal stability (TGA) in air atmosphere by thermogravimetric analysis. The results indicated a very similar morphology and crystallinity among them. The main differences were lie in the aggregation state and thermal stability. The aggregation state of the suspensions decreases in the order HCl < H2SO4:HCl < H2SO4 due to the increase in surface charge as determined by zeta potential measurements. The hydrolysis with a mixture of HCl and H2SO4 resulted in cellulose nanofibers with higher thermal stability than those hydrolyzed with H2SO4. The hydrolysis employed with a mixture of sulphuric and hydrochloric acids also showed a better dispersion than those suspensions of nanofibers obtained by hydrolysis with only HCl. (AU) | |