Correlation between the dielectric and the mechanical behavior of cellulose nanocomposites extracted from the rachis of the date palm tree

International Materials Research Meeting in the Greater Region: "Current Trends in the Characterisation of Materials and Surface Modification"

Ladhar, A.^1 ; Arous, M.^1 ; Kaddami, H.^2 ; Ayadi, Z.^3 ; Kallel, A.^1

LaMaCoP, Faculty of Sciences of Sfax, University of Sfax, BP 3018, Sfax, Tunisia^1

LCBM, Faculty of Sciences and Technologies, Cadi-Ayyad University, Marrakech

40000, Morocco^2

EEIGM, Equipe PMP-304, Nancy, France^3

关键词: Cellulose nanocrystal (CNC);    Dielectric strengths;    Dynamic mechanical analysis (DMA);    Interfacial polarization;    Nanofibrillated cellulose (NFC);    Reinforcement effects;    Reinforcing effects;    Relaxation phenomena;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/258/1/012001/pdf
DOI  :  10.1088/1757-899X/258/1/012001

来源: IOP

【 摘 要 】

In the present study, the dielectric and mechanical properties of natural rubber (NR) based nanocomposites are investigated. Cellulose nanofillers are used in two forms as reinforcing phase: nanofibrillated cellulose (NFC) and cellulose nanocrystals (CNC). In the dielectric study, different relaxation phenomena are detected: the α dipolar relaxation, the lignin and hemicelluloses relaxation, the water dipoles relaxation, the interfacial polarization and the ionic conduction. For the interfacial polarization, the dielectric strength Δ showed lower values for NFC-filled nanocomposites than CNC-filled samples. It was explained with higher interactions between induced dipoles and lower mobility, assuring a better adhesion between the NR and the NFC. Moreover, in tensile tests, the elastic modulus increases with filling indicating the reinforcement effect of nanofillers. In addition, the NR-NFC nanocomposites display the highest tensile modulus. This result shows the higher compatibility of NFC with the NR matrix, and the ensuing higher filler/matrix adhesion. In dynamic mechanical analysis (DMA), a significant reinforcing effect of NFC was shown. This effect is manifested with the high storage modulus E′, suggesting that the interactions between the NR matrix and the NFC fibers were stronger.