title: Study of a ternary diagram gel according to a methodology of experimental research.
abstract: Synopsis The purpose of this work was to compare two methods to determine the formulation of a gel: a 'classical'method previously used and a rational method using matrixes based on the Scheffe algorithm which is particularly useful in the study of these type of mixtures. This gel was composed of three products: C12-C15 Alcohols Benzoate, Cyclomethicone and Ethylene Vinyl Acetate Copolymer in water. The ratios of these compounds were studied according to five criteria: compatibility between phases, consistency, whiteness, cost and 'skin spreading'. To determine the incompatibility zone inside the ternary diagram, we carried out our study by a systematic sequential walk strategy (seven experiments). Three parameters (consistency, whiteness, cost) were optimized using the Scheffe algorithm. This method only needs a limited number of experiments on which to base an empirical mathematical model of the studied phenomena as a function of the different experimental factors. The formulation is therefore discussed as a function of the first degree linear, the second degree and a third degree 'reduced cubical'model. The validity of the possible models are also discussed and the 'reduced cubical'best fits our phenomena.
authors.affiliation: Université Paul Sabatier, 118, route de Narbonne, 31062 Toulouse Cedex, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Forestier
authors.forename: E
authors.initials: E
authors.lastname: Puech
authors.forename: J L
authors.initials: JL
authors.lastname: Tichadou