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Browsing by Author "Valencia Barragán, Concepción"
Now showing items 1-20 of 27
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AFM and SEM assessment of lubricating grease microstructures : influence of sample preparation protocol, frictional working conditions and composition
Roman, C.; Valencia Barragán, Concepción
; Franco Gómez, José María (Springer Verlag, 2016)
The microstructure of lubricating greases greatly conditions their in-service performance. In that sense, optimal testing protocols are required in order to accomplish their correct morphological characterization. This ... -
Assessment of Sustainability of Bio Treated Lignocellulose-Based Oleogels
Fajardo, Carmen; Blánquez, Alba; Borrero López, Antonio María; Valencia Barragán, Concepción (MDPI, 2021-01)
The development of biological strategies to obtain new high-added value biopolymers from lignocellulosic biomass is a current challenge for scientific community. This study evaluates the biodegradability and ecotoxicity ... -
Cellulose Pulp- and Castor Oil-Based Polyurethanes for Lubricating Applications: Influence of Streptomyces Action on Barley and Wheat Straws
Borrero López, Antonio María; Valencia Barragán, Concepción; Blánquez, Alba; Franco Gómez, José María (MDPI, 2020-11)
The replacement of mineral oils and non-renewable gelling agents is an imperative requirement for the lubricant industry in the near future. In this framework, cellulose pulp and castor oil are proposed as sustainable ... -
Chemical, thermal and viscous characterization of high-oleic sunflower and olive pomace acid oils and derived estolides
García Zapateiro, Luis Alberto; Franco Gómez, José María; Valencia Barragán, Concepción; Delgado Canto, Miguel Ángel; Gallegos Montes, Críspulo; Ruiz Méndez, M. V. (Consejo Superior de Investigaciones Científicas, 2013)
This work deals with the chemical, thermal and viscous characterization of a variety of estolides, prepared from higholeic sunflower and olive pomace acid oils, using different acid-catalyzed synthesis protocols and ... -
Desarrollo de formulaciones de grasas lubricantes biodegradables basadas en aceites vegetales y derivados celulósicos
Núñez Carballar, Nuria (Universidad de Huelva, 2016)
Este trabajo se centra en el uso de materiales renovables para preparar nuevas formulaciones potencialmente aplicables como grasas lubricantes biodegradables. En particular, se han utilizado diferentes pastas de celulosa ... -
Development of new thickening and/or gelling agents of vegetable oils from different lignocellusic fractions chemically modified through epoxidation
(Universidad de Huelva, 2019)During the last decades, the world is really concerned about the pollution and the negative effects that most chemicals and/or end-used products are causing on the environment, especially those derived from crude oil. ... -
Eco-Friendly Oleogels from Functionalized Kraft Lignin with Laccase SilA from Streptomyces ipomoeae: An Opportunity to Replace Commercial Lubricants
Domínguez, Gabriela; Blánquez, Alba; Borrero López, Antonio María; Valencia Barragán, Concepción; Eugenio, María Eugenia; Arias, María Enriqueta; Rodríguez, Juana; Hernández, Manuel (American Chemical Society, 2021)
This work demonstrates the usefulness of SilA laccase from Streptomyces ipomoeae to functionalize Kraft lignin to be used as a thickener in the preparation of biodegradable oleogels for lubricating purposes. First, ... -
Electrohydrodynamic Processing of PVP-Doped Kraft Lignin Micro- and Nano-Structures and Application of Electrospun Nanofiber Templates to Produce Oleogels
Rubio Valle, José F.; Sánchez Carrillo, María Carmen; Valencia Barragán, Concepción; Martín Alfonso, José Enrique; Franco Gómez, José María (MDPI, 2021)
The present work focuses on the development of lignin micro- and nano-structures obtained by means of electrohydrodynamic techniques aimed to be potentially applicable as thickening or structuring agents in vegetable ... -
Electrospun lignin-PVP nanofibers and their ability for structuring oil
Borrego, María; Martín Alfonso, José Enrique; Sánchez Carrillo, María Carmen; Valencia Barragán, Concepción; Franco Gómez, José María (2021-06-01)
This work explores the electrospinnability of low-sulfonate Kraft lignin (LSL)/polyvinylpyrrolidone (PVP) solutions in N,N-dimethylformamide (DMF) and the ability of the different micro- and nano-architectures generated to ... -
Influence of Base Oil Polarity on the Transient Shear Flow of Biodegradable Lubricating Greases
Fiedler, Martin; Sánchez Martínez, Rubén; Valencia Barragán, Concepción; Leopold, Claudia S.; Kuhn, Erik; Franco Gómez, José María (MDPI, 2015)
The scope of this study is to elucidate the physical mechanisms influencing the transient flow behavior of lubricating greases based on biogenic oleochemicals from a polarity point of view. This includes the mutually ... -
Influence of functionalization degree on the rheological properties of isocyanate-functionalized chitin- and chitosan-based chemical oleogels for lubricant applications
Gallego Calvo, Rocío; González, Mercedes; Fernández Arteaga, Jesús; Valencia Barragán, Concepción; Franco Gómez, José María (MDPI, 2014)
This work deals with the influence of functionalization degree on the thermogravimetric and rheological behaviour of NCO-functionalized chitosan- and chitin-based oleogels. Chitosan and chitin were functionalized using ... -
Isocyanate-Functionalized Chitin and Chitosan as Gelling Agents of Castor Oil
Gallego Calvo, Rocío; Fernández Arteaga, Jesús; Valencia Barragán, Concepción; Franco Gómez, José María (MDPI, 2013)
The main objective of this work was the incorporation of reactive isocyanate groups into chitin and chitosan in order to effectively use the products as reactive thickening agents in castor oil. The resulting gel-like ... -
Lignin effect in castor oil-based elastomers: Reaching new limits in rheological and cushioning behaviors
Borrero López, Antonio María; Wang, Ling; Valencia Barragán, Concepción; Franco Gómez, José María; Rojas, Orlando J. (Elsevier, 2021-02)
Lignin is demonstrated as an unprecedented reinforcing material that tailors the rheological and cushioning properties of castor oil-based polyurethane elastomers, expanding their viscoelastic moduli by four orders of ... -
Lignocellulosic Materials for the Production of Biofuels, Biochemicals and Biomaterials and Applications of Lignocellulose-Based Polyurethanes: A Review
The present review is devoted to the description of the state-of-the-art techniques and procedures concerning treatments and modifications of lignocellulosic materials in order to use them as precursors for biomaterials, ... -
Modification of Alkali Lignin with Poly(Ethylene Glycol) Diglycidyl Ether to Be Used as a Thickener in Bio-Lubricant Formulations
Cortés Triviño, Esperanza; Valencia Barragán, Concepción; Delgado Canto, Miguel Ángel; Franco Gómez, José María (MDPI, 2018-06)
Considerable efforts are currently being made by the academic community and industry, aiming to develop environmentally friendly lubricants with suitable technical features for their performance. In this context, lignin ... -
Oleins as a source of estolides for biolubricant applications
García Zapateiro, Luis Alberto; Delgado Canto, Miguel Ángel; Franco Gómez, José María; Valencia Barragán, Concepción; Ruiz Méndez, M. V.; Garcés, R.; Gallegos Cázeres, Leticia (Consejo Superior de Investigaciones Científicas, CSIC: Instituto de la Grasa, 2010-06)
This study deals with the synthesis of estolides from high-oleic sunflower oil oleins, and its potential use as viscosity modifiers for biolubricant applications. Synthesis reactions were monitored for 24 h. Estolide ... -
On the Steady-State Flow and Yielding Behaviour of Lubricating Greases
Delgado Canto, Miguel Ángel; Secouard, Sebastien; Valencia Barragán, Concepción; Franco Gómez, José María (MDPI, 2019)
Practical steady-state flow curves were obtained from different rheological tests and protocols for five lubricating greases, containing thickeners of a rather different nature, i.e., aluminum complex, lithium, lithium ... -
Populus alba L., an Autochthonous Species of Spain: A Source for Cellulose Nanofibers by Chemical Pretreatment
Ibarra, David; Martín Sampedro, Raquel; Wicklein, Bernd; Borrero López, Antonio María; Valencia Barragán, Concepción; Valdehíta, Ana; Navas, José M.; Eugenio, María Eugenia (MDPI, 2022)
In order to identify new sustainable sources for producing cellulose nanofibers (CNFs), fast-growing poplar (Populus alba L.) wood was evaluated herein. For that purpose, bleached poplar kraft pulp was produced and ... -
Reversible pH-sensitive chitosan-based hydrogels. Influence of dispersion composition on rheological properties and sustained drug delivery
Iglesias González, María Nieves; Galbis Fuster, Elsa; Valencia Barragán, Concepción; Paz Bañez, María Violante de; Galbis Pérez, Juan Antonio (MDPI, 2018)
The present work deals with the synthesis of micro-structured biomaterials based on chitosan (CTS) for their applications as biocompatible carriers of drugs and bioactive compounds. Twelve dispersions were prepared by means ... -
Rheological and tribological approaches as a tool for the development of sustainable lubricating greases based on nano-montmorillonite and castor oil
Martín Alfonso, José Enrique; Martín Alfonso, María José; Valencia Barragán, Concepción; Cuberes, María Teresa (Springer Open, 2020-10)
This study investigates the development of novel montmorillonite/castor oil blends to formulate sustainable lubricating greases to promote the replacement of petrochemicals industry-derived materials by substances obtained ...
