RT Journal Article
T1 Valorization of Kraft Lignin as Thickener in Castor Oil for Lubricant Applications
A1 Borrero López, Antonio María
A1 Santiago Medina, F. J.
A1 Valencia Barragán, Concepción
A1 Eugenio, María Eugenia
A1 Martín Sampedro, Raquel
A1 Franco Gómez, José María
AB It is known that large amounts of residual lignin are generated in the pulp and paper industry. A new alternative for Kraft lignin valorization, which consists of first a chemical modification using a diisocyanate and then the efficient dispersion in castor oil to achieve stable gel-like systems, is proposed in this work. Rheological properties and microstructure of these materials were determined by means of small amplitude oscillatory shear tests and viscous flow measurements and atomic force microscopy observations, respectively. Moreover, both standardized penetration tests and tribological assays, usually performed in the lubricant industry, were carried out to evaluate the performance characteristics as lubricating greases. Linear viscoelasticity functions are affected by the lignin/diisocyanate ratio and thickener concentration. The thermorheological response evidenced a softening temperature of around 105 °C. The microstructure of these gel-like dispersions is composed of interconnected thin fibers, homogeneously distributed in castor oil. Moreover, the NCO-functionalized lignin gel-like dispersions studied show lower friction coefficients than traditional lubricating greases.
PB Tech Science Press
SN 2164-6325
SN 2164-6341 (electrónico)
YR 2018
FD 2018
LK https://hdl.handle.net/10272/24647
UL https://hdl.handle.net/10272/24647
LA eng
NO Borrero-López, A. M., Santiago-Medina, F. J., Valencia, C., Eugenio, M. E., Martin-Sampedro, R., & Franco, J. M. (2018). Valorization of Kraft Lignin as Thickener in Castor Oil for Lubricant Applications. In Journal of Renewable Materials (Vol. 6, Issue 4, pp. 347–361). Computers, Materials and Continua (Tech Science Press). https://doi.org/10.7569/jrm.2017.634160
NO This work is part of two research projects (CTQ2014-56038-C3-1R and RTA2015-00051-00-00) sponsored byMINECO-FEDER (70% European cofunding rate) andINIA programs, respectively.
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026