Solubilizing and Hydrotropic Properties of Isosorbide Monoalkyl- and Dimethyl-Ethers

Isosorbide is a diol readily obtained from starch that can be used as a polar building block for the synthesis of derivatives ranging from solvents to surfactants: dimethyl isosorbide (DMI) is a “sustainable solvent” already on the market, used notably in cosmetic and pharmaceutical formulations; monoalkyl derivatives of isosorbide are non-ionic hydrotropes that could be potential substitutes to short-chain glycol ethers. The use of these isosorbide derivatives as bio-sourced alternatives to petroleum-derived products for applications such as compatibilizers in liquid detergent formulations or solubilizing agents in aqueous hard-surface cleaning is discussed in this paper. DMI reveals to have interesting coupling properties for the former applications, whereas the monopentyl ether of isosorbide (C₅Iso) is a particularly efficient hydrotrope for the latter.