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Browsing by Author "Valencia Barragán, Concepción"
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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 ... -
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. ... -
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, Rocio; 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, Rocio; 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 ... -
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 ... -
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 ... -
Rheology of lignin-based chemical oleogels prepared using diisocyanate crosslinkers : effect of the diisocyanate and curing kinetics
Borrero López, Antonio María; Valencia Barragán, Concepción; Franco Gómez, José María (Elsevier, 2017)
In this work, alkali lignin together with different diisocyanates (hexamethylene diisocyanate (HDI), isophorone diisocyanate (IDI), toluene diisocyanate (TDI) and 4,4′-methylenebis (phenyl isocyanate) (MDI)) have been ... -
Rheology of oleogels based on sorbitan and glyceryl monostearates and vegetable oils for lubricating applications
Sánchez Martínez, Rubén; Franco Gómez, José María; Delgado Canto, Miguel Ángel; Valencia Barragán, Concepción; Gallegos Montes, Críspulo (Consejo Superior de Investigaciones Científicas, 2011)
Oleogels based on sorbitan and glyceryl monostearates and different types of vegetable oils, potentially applicable as biodegradable alternatives to traditional lubricating greases, have been studied. In particular, the ... -
Tribological behaviour of novel chemically modified biopolymer-thickened lubricating greases investigated in a steel–steel rotating ball-on-three plates tribology cell
Gallego Calvo, Rocio; Cidade, T.; Sánchez Martínez, Rubén; Valencia Barragán, Concepción; Franco Gómez, José María (Elsevier, 2016)
In this work, model renewable and biodegradable lubricating greases based on castor oil and chemically modified biopolymers (methylcellulose, chitin and cellulosic pulp) were tribologically characterized in a steel–steel ... -
Uso de polímeros reciclados y convencionales como modificadores de las propiedades reológicas de grasas lubricantes
Martín Alfonso, José Enrique (2010)
Esta tesis doctoral se ha centrado en el estudio de la viabilidad técnica de la utilización de polímeros termoplásticos reciclados y convencionales, como aditivos o como agentes espesantes en el diseño de grasas lubricantes, ...
