Abstract S-Alkylthiocarboxylic acids and their potassium salts were prepared by photoaddition of α-olefins (C 10, C 12, and C 14) with mercapto carboxylic acids such as thiomalic acid, thiopropionic acid, and thioglycolic acid. The physicochemical solution properties and thermal stabilities for three series of thiosurfactants were evaluated. S- Alkylthiocarboxylic acids that contain bridged S-bonds provide excellent thermally stable ...