Beyond conventional surfactants
Since many years it has become obvious that conventional surfactants made from one C8-C20 hydrophobic tail and one hydrophilic head are not up to the challenges posed by demanding industrial applications involving for example high ionic strength, extreme pressure and temperature, high dispersed phase volumes. Original emulsifiers/dispersants have sometimes allowed to respond to these emerging needs, but whatever the structures designed they always involved the use of chemically synthesized interfacial active agents. Froth formation is a recurring example of unwanted effect e.g. in bio-reactors and bio-processes. In a truly innovative approach researchers have now developed a device that could solve this problem without having to use interfacial active defoamers.
In one of my earlier columns (1) I raised the flag that in certain instances, the conventional surfactants may face the risk of substitution by other chemicals. For example the food and personal care industries are expressing an increasing interest in Pickering emulsions and emulsifiers.
In the past, polymeric surfactants of original structure have resulted in significant technological progresses, enabling to produce emulsions and dispersions that can perform in extreme conditions of ionic strength, temperature, pressure and dispersed phase volumes, like emulsion explosives, steel mills hydraulic fluids, inverse acrylamides polymerisation. I had the opportunity to highlight this in several articles, for example in those shown below (2-4).
Let be clear upfront, there is nothing in there that should cause sleepless nights to the big ethoxylators, sulphonators and sulphators: the nearly standard structures consumed by household detergents, personal care, crop protection and the many fragmented industrial applications will continue to be used in huge and growing volumes in the foreseeable future. However it is a signal that the conventional surfactants are not al ...