Nonionics as Intermediates for Ionic Surfactants

The surfactant properties of nonionic surfactants (see previous chapters) are modified or further improved with regard to certain applications by introduction of an ionic group. This derivatization is usually carried out by reaction at the terminal hydroxyl group of the nonionic surfactant, typically being a polyoxyethylene or a glycerol derivative, to build up sulfates, phosphates, and carboxylates as the anionic products [Eq. (1)] [1,2]. The most important feedstocks for these reactions are the polyoxyethylene alcohols or alkyl polyoxyethylene alcohols. It is estimated that the annual growth rate of polyoxyethylene alcohols as the typical nonionic surfactant is 4% [3]. The major reason is the gradual substitution of the polyoxyethylene alkylphenols, which are still used in certain regions of the world. This development, of course, affects the use of the corresponding ionic derivatives as well. (1) RO ( C 2 H 4 O ) X H →   →  RO ( C 2 H 4 O ) X ZNa                       Z  =  SO 3 ,  PO 3 ,  CO 2 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203745649/4b94017f-3fd5-4c05-bd31-a5e0837eeb19/content/eq53.tif"/>