Abstract
Four series (anionic, cationic, zwitter-ionic and POE nonionic) of surfactants with peptide joints were prepared from various N-dodecyl-α-amino acids (Scheme-1, Table-1). The aqueous properties (Krafft point, cloud point, cmc, surface tension) and gross effects (foaming, emulsifying, detergency) of these products were examined and compared with those of surfactants without peptide joints for each series.
The effects of peptide joints on aqueous properties were found to depend primarily on the hydrophobicity of the α-amino acid used (Table-6, -7). Glycine and alanine joints generally caused on increase in hydrophilicity and a slight change in cmc and surface tension for all series studied.
Some nonionics having hydrophilic peptide joints and shorter POE chains had both Krafft and cloud points in the temperature range from 2090°C and exibited high surface activity (Table-7). These nonionics were effective emulsifying agents (O/W) against relatively polar oils (Fig. -4) and showed good detergency (Table-8),
The surfactants with peptide joints were highly biodegradable.
