O PAPEL vol. 82, num. 3, pp. 88 - 92 - MAR 2021
ABSTRACT
To evaluate the defibrillation process during the production
of MFC, equipment control and key parameters such as speed
and number of passes in the defibrillator mill were tested.
In addition, conditions inherent to samples such as pulp
type and consistency of initial suspension were evaluated. It
should be noted that for all morphological indices evaluated,
it was noted that the speeds of 1,500 and 2,200 rpm were the
ones that resulted in a more efficient defibrillation process, in
contrast to the 2,900-rpm speed. Very high speeds (e.g., 2,900
rpm) do not allow for efficient shear and defibrillation times
for MFC production. Factors such as viscosities and number
of passes in the defibrillator have an exponential correlation,
while parameters for controlling preparation of the initial fiber
suspension such as consistency (2% and 4% in this study) did
not show any correlation and influence on the production of
MFC using this grinder equipment in laboratory. Consistencies
above 6% should be investigated. The increase in the number
of passes in the laboratory grinder promotes a reduction in
the size of fibers in order to produce a suspension with a very
homogeneous character, so the formation of films from these
suspensions confirms the reduction of roughness and formation
of more homogeneous surface that influences the transparency
values for these films. Therefore, the production of MFC can
be controlled for morphological parameters and other indirect
measures such as viscosity of MFC suspensions.
Keywords: MFC, defibrillation, grinder, nanocellulose