GUIDO BOGNOLO
WSA Associates
Schuttershof 2, 3078 Everberg, Belgium
Member of HPC Today’s Scientific Advisory Board

Abstract

Despite the progresses in interfacial science and the demands from the markets, the concept of structure/performance relationship is still poorly understood and rarely put in practice by surfactants formulators. It is also a surprising observation across the industry that formulation technologists do not seem to be more conversant with the fundamental principles controlling the interfacial phenomena than their colleagues of one (not to say two) generations ago. The fact that in the literature structure/performance is generally presented as the correlation between surfactants structure and their physico-chemical properties (as opposed to “performance in use”) do not encourage a broad use of the concept in formulating surfactants. The situation is of particular concern at a time when the interest in sustainability begins to affect deeply not only the sectors of the household detergents and of the safety conscious personal care, but also other markets. The article suggests that unless credible answers are developed, there are distinct risks that the traditional surfactants lose ground in the short and medium term and perhaps even face replacement by non-surfactants technology in the longer term. The article concludes with suggestions on how the principles of interfacial science and the concepts of structure/performance relationships can be revitalized to meet the challenges ahead.

INTRODUCTION
An amazing number of surfactants classes and sub-classes were developed since the chemistry of synthetic surface active agents blossomed in the decades between its onset in, say, the 1930 ties, its peak in the 1950ties-1960ties and ,albeit at a reduced intensity during the late 1960ties-1970ties. The recognition of the contribution of surface active agents in improving dramatically the household and personal cleaning and hygiene, the enhancement of industrial products, the synthesis of new surfactants families, the relatively low capital investments for production units created an atmosphere of optimism and confidence in the surface active agents industry that was not going to be repeated since. I refer to those days as the “golden age” of the surface active agents, when the industry could post attractive benefits, was prepared to invest in basic and applied research and could offer technologically innovative options to a responsive market. It must be recognized however that innovation was in most cases the result of what I call “the meccano approach”:
“The linking of hydrophobes and hydrophiles in a matrix-designed, trial ...