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Ionic Liquids are promising candidates for next generation green lubricants. We have synthesized 39 Tetraalkylammonium Alkyl Ether Carboxylate Ionic Liquids and tested them for their lubricant capabilities. We measured friction coefficient to assess the transition from the boundary to the hydrodynamic lubrication, the hydrodynamic area and the minimum friction value. Some Ionic Liquids are capable of forming a hydrodynamic layer fully separating two specimens. Compounds with short C-chain of the cationic part show poor tribological behaviour. Similarly, increasing the PO-degree of the anionic part lowers the lubrication power. An increase of the C-chain length improves the tribological behaviour, i.e. the minimum friction value becomes lower. This is due to the formation of a uniform tribolayer of the long-chain carboxylic acids. Higher viscosity of the Ionic Liquids results in low friction coefficients and the development of a hydrodynamic layer. This is due to a strong hydrodynamic pressure, which is formed by the more viscous compound. Addition of small amounts of Ionic Liquids to low performance oils increases their capability to from tribolayers and thus improves their lubricant capability.

The highest effectiveness of detergency for nonionic surfactants is observed in the proximity of the cloud point. This phenomenon is primarily influenced by surfactant molecular structure, such as carbon chain length and type of the hydrophilic components. Target of this investigation is to identify a relationship between the cloud point and the structure of nonionic surfactants based on ethoxylated (CnEm), ethoxylated‐propoxylated (CnEmPp) and propoxylated‐ethoxylated (CnPpEm) fatty alcohols. Three hundred and fifty nonionic surfactants have been prepared for this purpose. These surfactants differ in the C‐chain lengths, C4/C6 to C20/C22, and the amount of ethylene oxide (EO range [n] 2–22 ethoxylation) and propylene oxide (PO range [p] 0–12 propoxylation) moieties. Mapping the differences in the performance allows us to propose a high‐accuracy topological model describing the structure influence on the cloud point.

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During synthesis of the surfactants, several byproducts are formed that impact the physico-chemical properties as well as the quality of the product. Removal of these impurities is hence of vital interest, but the purification has remained chemically challenging. In this work, the ion exchange resin type I strong base anion polymeric catalyst was used to remove impurities such as remaining raw material and byproducts from different ether carboxylic acid surfactants. The efficiency of this preparative purification method was determined through analysis of the product composition using different analytical techniques such as titrimetric acid and saponification value determination, gas chromatography, Infrared (IR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The results showed the high efficiency of the purification of the ether carboxylic acid surfactants using ion exchange resin. For all purified samples, the amount of byproducts such as esters and remaining raw material was found significantly reduced. Pure anionic surfactants (>90%) were obtained. Its ease of use and high efficiency render the method suitable for carboxymethylated surfactants. Additional investigations on industrial scales and further surfactant purification are yet to be analyzed.