Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

Study of morphological properties and rheological parameters of cellulose nanofibrils of cocoa shell (Theobroma cacao L.)

2019; Elsevier BV; Volume: 214; Linguagem: Inglês

10.1016/j.carbpol.2019.03.037

1879-1344

Lucas Oliveira Souza, Ozana Almeida Lessa, Matheus Cordazzo Dias, Gustavo Henrique Denzin Tonoli, Denilde Vilas Bôas Rezende, Maria Alice Martins, Isabelle Cristina Oliveira Neves, Jaime Vilela de Resende, Elisângela Elena Nunes Carvalho, Eduardo Valério de Barros Vilas Boas, Julieta Rangel de Oliveira, Marcelo Franco,

Polysaccharides and Plant Cell Walls

Cocoa shell was evaluated as a precursor for cellulose nanofibrils (NFCs) using mechanical defibrillation. Its morphology was analysed using optical microscopy and scanning electron microscopy with field emission. Rheological and mechanical behaviour were evaluated through flow curves with a strain rate ranging from 0 to 300 s−1 at 25 °C and by means of oscillatory frequency sweeps (0.01 Hz–10 Hz) and shear stress (3 Pa). The thermal-mechanical behaviour was determined by a temperature sweep with a heating rate of 3 °C min−1 and a temperature range of 25 °C–100 °C. Micrographs identified the presence of protoxilem with a mean diameter of 23.34 nm. The flow curve showed the characteristic behaviour of a pseudoplastic fluid. The storage module (G′) and the loss modulus (G″) were dependent on the frequency applied, indicating that the material exhibits a weak gel characteristic. The viscoelastic characteristics were influenced by temperature. Therefore, cocoa shell is a new alternative in the production of nanocellulose.