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The objective of this study was to characterize on the chemical, mechanical, electrical and thermal properties of nanofibrillated cellulose based polyvinyl alcohol (PCNF) and silica (SiCNF) films obtained from Pulpzyme HC 2500 and Celluclast 1.5 L enzyme treated kraft-NaBH 4 pulps. Morphological alterations were monitored with SEM. Thermal stability, chemical characterization and crystallization were determined using TGA and FT-IR. Young's and storage moduli of the films were determined via a universal testing machine and DTMA. Dielectric properties were evaluated using an impedance analyzer. In the PCNF films, new vibrations and chemical shifts were observed. The crystallinity values of the SiCNF films calculated from the FT-IR were in agreement with the TGA results, revealing that the lowest crystallinity value was in the SiCNF. The higher Young modulus and elongation at break value were obtained in the neat the CNF films while the lowest values were observed in the neat SiCNF films. However, the SiCNF films revealed higher thermo-mechanical property. The PCNF and SiCNF films exhibit more visible dielectric behavior than that of the neat CNF films. Higher thermal stability, thermo-mechanical and mechanical properties were determined in the Pulpzyme HC 2500 enzyme treated films. Hence, this study evidenced that the properties of CNF films having different matrix are influenced by both the enzymes employed. [ABSTRACT FROM AUTHOR]

This study reports on the effects of organic polyvinyl alcohol (PVA) and inorganic silica polymer on properties of Celluclast-treated nanofibrillated cellulose composites. Nanofibrillated cellulose was isolated from Eucalyptus camaldulensis and prior to high-pressure homogenizing was pretreated with Celluclast enzyme in order to lower energy consumption. Three nanocomposite films were fabricated via the casting process: nanofibrillated cellulose (CNF), nanocellulose-PVA (CNF-P) and nanocellulose-silica (CNF-Si). Chemical characterization, crystallization and thermal stability were determined using FT-IR and TGA. Morphological alterations were monitored with SEM. The Young’s and storage moduli of the nanocomposites were determined via a universal testing machine and DTMA. The real and imaginary parts of permittivity and electric modulus were evaluated using an impedance analyzer. The crystallinity values of the nanocomposites calculated from the FT-IR were in agreement with the TGA results, showing that the lowest crystallinity value was in the CNF-Si. The CNF-P displayed the highest tensile strength. At a high temperature interval, the storage modulus of the CNF-Si was greater than that of the CNF or CNF-P. The CNF-Si also exhibited a completed singular relaxation process, while the CNF and the CNF-P processes were uncompleted. Consequently, in terms of industrial applications, although the CNF-P composite had mechanical advantages, the CNF-Si composite displayed the best thermo-mechanical properties. [ABSTRACT FROM AUTHOR]

This study aims at using microcrystalline cellulose (MCC) and lignin in place of EPDM and carbon black with specified amounts to investigate the chemical, thermal, rheometric, mechanical, thermo-aging and morphological properties of EPDM elastomers. At the end of the study, the introduction of the MCC and lignin enabled higher elastic modulus and tear strength unlike tensile strength by revealing minor chemical shifts and lower thermal stability. In addition, the MCC and lignin facilitated the vulcanization process with fewer torque values by dispersing mostly homogeneously in the matrix. It was shown that all of the mechanical values were found to be in the range of the specified standard after the replacement of the MCC and lignin. [ABSTRACT FROM AUTHOR]