Formulation and optimization by experimental design of eco-friendly emulsions based on d-limonene

d-Limonene is a natural occurring solvent that can replace more pollutant chemicals in agrochemical formulations. In the present work, a comprehensive study of the influence of dispersed phase mass fraction, ϕ, and of the surfactant/oil ratio, R, on the emulsion stability and droplet size distributi...

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Detalles Bibliográficos
Autores: Pérez Mosqueda, Luis María, Trujillo-Cayado, Luis Alfonso, Carrillo de la Fuente, Francisco, Ramírez del Amo, Pablo, Muñoz García, José
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/180396
Acceso en línea:https://hdl.handle.net/11441/180396
https://doi.org/10.1016/j.colsurfb.2015.02.030
Access Level:acceso abierto
Palabra clave:d-limonene
Emulsion
Ostwald ripening
Pluronic
Response surface methodology
Descripción
Sumario:d-Limonene is a natural occurring solvent that can replace more pollutant chemicals in agrochemical formulations. In the present work, a comprehensive study of the influence of dispersed phase mass fraction, ϕ, and of the surfactant/oil ratio, R, on the emulsion stability and droplet size distribution of d-limonene-in-water emulsions stabilized by a non-ionic triblock copolymer surfactant has been carried out. An experimental full factorial design 32 was conducted in order to optimize the emulsion formulation. The independent variables, ϕ and R were studied in the range 10–50 wt% and 0.02–0.1, respectively. The emulsions studied were mainly destabilized by both creaming and Ostwald ripening. Therefore, initial droplet size and an overall destabilization parameter, the so-called turbiscan stability index, were used as dependent variables. The optimal formulation, comprising minimum droplet size and maximum stability was achieved at ϕ = 50 wt%; R = 0.062. Furthermore, the surface response methodology allowed us to obtain the formulation yielding sub-micron emulsions by using a single step rotor/stator homogenizer process instead of most commonly used two-step emulsification methods. In addition, the optimal formulation was further improved against Ostwald ripening by adding silicone oil to the dispersed phase. The combination of these experimental findings allowed us to gain a deeper insight into the stability of these emulsions, which can be applied to the rational development of new formulations with potential application in agrochemical formulations.