Innovative surfactants developments
Surfactants have a wide range of applications, and their popularity is only increasing since the second world war when they firstly replaced soaps. Due to environmental regulations, consumer sustainability awareness and potential difficulties with fossil fuel supply, the popularity of sustainable surfactants is rising continuously and there are a significant number of innovations over the past years. Difficulties when formulating with alternatives to conventional surfactants and cost associated is still preventing the eco surfactant market to overtake the traditional one.
SURFACTANTS AND THEIR CHEMICAL STRUCTURE
Surfactants are surface-active ingredients that reduce the interfacial energy of contact phases with different polarity degrees, like for example oil/water and, or water/air (1). This is possible because of their specific amphiphilic structure with hydrophobic and hydrophilic moieties in the same molecule. The hydrophobic tail is usually hydrocarbon, and the classification of the surfactants depends on the charge of the hydrophilic head (2).
Anionic surfactants have a negative charge on the hydrophilic head and good foaming and detergency properties. They represent the majority of the global market with around 45% of the global consumption (3). Anionic surfactants are cheap and widely used across different industries due to their favourable properties. Alcohol sulphates and alcohol ether sulphates are the most well-known traditional anionic surfactants (4).
Non-ionic surfactants with no charge on the hydrophilic head are used as wetting agents, emulsifiers and foaming agents (5). With low cost, good biodegradability, and low toxicity the non-ionic surfactants represent ...