Synthesis and characterization of glucosamide‐based trisiloxane gemini surfactants

A new family of glucosamide‐based trisiloxane gemini surfactants of the general formula (CH2OCH2)n (Me3SiOSiMeR1OSiMe3)2 (where R1=(CH2)3NR2(CH2)2NHCO (CHOH)4CH2OH; R2=CH2CH(OH)CH2OCH2; and n=0, 1, or 2) was prepared and characterized, both structurally and as aqueous surfactants. The monomer was prepared by amidation of the precursor amine functional trisiloxane with d‐gluconic acid δ‐lactone. Gemini surfactants were then prepared by the alkylation of the precursor secondary amine with oligoethylene glycol diglycidyl ethers. They were structurally and elemental analysis. Members of this family reduced the surface tension of water to approximately 21 mN/m at concentration levels of 10−5 mol/L. These gemini compounds showed two critical aggregation concentration values. This behavior resulted from the formation of premicellar aggregates before true micelles were formed.