Morphological, Physical and Thermal Characterization of Microfibrillated Cellulose

Abstract

The aim of this study was to characterize microfibrillated cellulose (MFC) produced with a Masuko Sangyo Super Masscolloider using bleached and unbleached pulp of Eucalyptus spp. The MFC was characterized regarding morphology (TEM), crystallinity, viscosity, zeta potential and thermal properties (TGA). Regardless of the fiber type, the processing dramatically reduced the dimensions of the material, so as to obtain structures with nanometric dimensions. MFC produced with unbleached pulp preserved the original brown color of the pulp, which may be advantageous for some applications in the packaging sector, while films produced with bleached pulp were more translucent. The MFC showed lower values of viscosity and crystallinity index in relation to cellulosic pulp. The zeta potential was influenced by the type of fiber used. The main thermal transitions in MFC occurred after 200 ºC, demonstrating the potential of this material forhigh-temperature applications.

Preliminary evaluation of the incorporation of cellulose nanofibers as reinforcement in waterborne wood coatings

“…The bleached MFC had an increase in ICr after the mechanical defibrillation process, which resulted in greater exposure of the fibrils than in the cellulose fiber sample, increasing its ICr, but did not cause fiber degradation and tearing to the point of affecting the index. Lengowski et al (2018) and Viana et al (2019) found ICr values close to 80 % for unbleached pine cellulose fiber, near those found in work, which is consistent with other published studies.…”

Influence of the addition of microcrystalline cellulose (Mcc) on structural properties of cellulose nanofibrils (NFC) suspensions and films

“…The pulp was disintegrated in a blender (power 450 W) for approximately ten minutes before passing to the Supermascolloider MKCA6-2J colloidal mill through 10 passes at 1500 rpm rotation and at a solid concentration (consistency) of 1 %. Several previous studies (Viana et al, 2019;Potulski, 2016;Lengowski et al, 2018) have shown that the fiber dimensions do not change after five passes, but there is a consequent degradation of the cellulose.…”

“…For the analysis of the structures in the suspensions, a Transmission Electron Microscope (TEM) model Jeol JEM 1200 EXII was used with a resolution of 0.5 nm (600 thousand X); each suspension was prepared at five ppm diluted in distilled water and dripped onto the surface of the observation screen and transferred to a desiccator for drying at room temperature (Lengowski et al, 2018). Through the electron micrographs obtained from the TEM, a particle sizing analysis was performed with a sampling intensity of 60 units in an area of 2.62 mm 2 , with the help of an image analysis software and a thresholding filter (ImageJ).…”

INFLUÊNCIA DA ÁREA FOLIAR EM MINIESTACAS DE Azadirachta indica A. Juss

“…Muitos estudos já comprovaram a eficiência da utilização da nanocelulose como aditivo na fabricação de papel, seja para melhora de propriedades de resistência, melhora nas propriedades de barreira em embalagens de alimentos, melhora do brilho de papel, melhora da printabilidade, redução da gramatura do papel sem perdas nas propriedades mecânicas, melhora das propriedades térmicas e prover capacidade antimicrobianas em embalagens (SAINI et al, 2016;LENGOWSKI et al, 2018;LENGOWSKI et al, 2019a;SALAS et al, 2019).…”