The Behaviour of Dyes in Aqueous Solutions. Part II – Anionic Dye – Nonionic Surfactant Interactions

A spectrophotometric method has been used to study the interactions of some monoazo anionic dyes with a series of nonionic surfactants of different ethylene oxide chain length. The interaction between the dyes and the surfactants has been shown to be hydrophobic in nature with the extent of interaction increasing with increasing hydrophobicity of alkyl side-chains on the dyes.