02557naa a2200277 a 450000100080000000500110000800800410001902400520006010000150011224501320012726000090025952017300026865000210199865000130201965300240203265300170205665300180207365300170209170000240210870000190213270000200215170000210217170000190219270000170221177300510222821643082024-06-26 2023 bl uuuu u00u1 u #d7 ahttps://doi.org/10.1007/s10570-023-05546-52DOI1 aGENTIL, M. aInfluence of residual lignin on Acacia mearnsii De Wild nanofibrillated cellulose suspensions and films.h[electronic resource] c2023 aStudies on plant-derived nanocellulose are mainly carried out with lignin-free materials. However, lignocellulosic materials can be used as an alternative raw material, mainly due to their low cost and low environmental impact. This work aimed to study and compare the influence of residual lignin on the nanofibrillation process, on the properties of the nanofibrils and the films formed from the cel- lulose nanofibrils of Acacia mearnsii De Wild. The cellulosic pulp was subjected to bleaching to remove the lignin and obtain the bleached pulp. Bleach and unbleached pulps were subjected to mechanical defi- brillation to obtain cellulose nanofibrils. The effects of defibrillation and residual lignin content were ana- lyzed by characterizing the suspensions and nanocel- lulose films formed from this material. In addition, an energetic study of the production process of dif- ferent cellulose nanofibrils was carried out, consid- ering the different levels of residual lignin present in the material. The results demonstrated that the residual lignin presence preserved the thermal prop- erties and provided changes in the morphology of the films, the suspensions showed colloidal stability from pH 5.0 (between |25| and |30| kV), the increase of the lignin content in the pulp caused a slight expres- sive improvement in the antioxidant activity and a decrease in the suspension viscosities, which fitted the Herschel–Bulkley model well (R2 > 0.98). The mechanical properties of the films [127 MPa (NBR) and 75 MPa (N16)] and the energy consumption to produce nanofibrils [0.324 kWh (NBR) and 0.180 kWh (N16)] showed significant differences, point- ing to the influence of residual lignin present in the materials. aAcácia Mearnsii aCelulose aCellulose nanofilms aKappa number aNanocellulose aNanocelulose1 aMAGALHAES, W. L. E.1 aMARTINS, T. R.1 aMALLMANN, A. S.1 aMALUCELLI, L. C.1 aCOLDEBELLA, R.1 aPEDRAZZI, C. tCellulosegv. 30, n. 17, p. 10867-10877, 2023.