A novel class of spacer-directed Gemini surfactants: a comprehensive study of their structure-property relationships and efficiency in polyester fabric modification

This study presented the synthesis, characterization, and functional evaluation of a novel family of zwitterionic Gemini surfactants using 2,3-dibromosuccinic acid as a unique difunctional spacer. This spacer effectively and consistently incorporated two amidoamine/alkyl dimethyl amine hydrophobes due to its strong polarity, reactivity, and symmetrical structure. 2,3-dibromosuccinic acid improves surface-active performance by adding ionic stability and structural rigidity. This study indicated that this is the first recorded application of 2,3-dibromosuccinic acid in the synthesis of novel Zwitterionic Gemini surfactants. The Gemini surfactants synthesized were characterized by FTIR, NMR, and Mass spectroscopy. They were synthesized from amidoamines based on fatty acids, such as lauric, caprylic/capric, and 2-ethylhexanoic acids, and dodecyldimethyl amine. The physicochemical properties, viz. surface tension, critical micelle concentration (CMC), C20 reduction, foaming behaviour, and wettability, were studied and compared with those of a commercial monomeric betaine. Application Properties like whiteness index, softness, and antistatic performance on polyester fibre and fabrics were also evaluated. These surfactants are found as effective as non-ionic surfactants, softening polyester fabric, reducing static electricity, and achieving remarkable foam stability when applied to textiles. This research work also highlights an innovative molecular design approach that utilizes 2,3-dibromosuccinic acid, paving the way for next-generation zwitterionic surfactants.