Desarrollo de formulaciones de grasas lubricantes biodegradables basadas en aceites vegetales y derivados celulósicos
- Núñez Carballar, Nuria
- José María Franco Gómez Director
- Concepción Valencia Barragán Director
Defence university: Universidad de Huelva
Fecha de defensa: 05 February 2016
- Francisco López Baldovín Chair
- Nuria Calero Romero Secretary
- Gil Garrote Velasco Committee member
Type: Thesis
Abstract
This work deals with the use of renewable raw materials to prepare new formulations potentially applicable as biodegradable lubricating greases. In particular, different cellulosic pulps from different raw materials and submitted to different process and/or several treatments have been used as biothickener agents; castor and high oleic sunflower oils have been used as base oils and ethyl cellulose has been tested as gelling agent in the oil medium. The rheological, mechanical and thermal properties of these formulations were analyzed in order to know the influence that biodegradable polymers used as thickeners exert on the find properties and performance. The effect of the origin of cellulose pulp, i.e., polymerization degree and composition, as well as pulping conditions on the rheological properties of find dispersions in castor oil was studied. Ethyl cellulose was also obtained from industrial Kraft cellulose pulp and used as gelling agent in the manufacture of the greases studied. Different degree of éthylation was obtained by modifying reaction time, temperature and glucose/ethyl ratio. As a result of this investigation, finally, a series of formulations with gel characteristics are proposed to be potentially used as 100% biodegradable lubricatiing greases.