Synthesis and characterization of oleic succinic anhydrides: Structure-property relations

International audienceAlkenyl succinic anhydrides (ASA) were prepared by an‐ene reaction of n‐alkyl (C1 to C5) oleates with maleic anhydride. The purified compounds were characterized by FTIR, 1H NMR, and MS analytical methods to elucidate their structures. Their physicochemical properties were systematically studied and found to depend on the length of the alkyl radical. Structure‐property relations were established for viscosity, m.p., and density. The combination of a long hydrophobic chain and a highly polar group with density values close to that of water implied good emulsification properties for some of these molecules. Comparison of the thermal properties of alkyl oleates and their respective ASA demonstrated that the grafting of maleic anhydride allowed the synthesis of compounds with very low melting temperatures (less than −60°C) and good stability at high temperatures (greater than 350°C) under both air and helium atmospheres. All these properties suggest a strong potential for application in the biolubricant or surfactant fields. The combined influences of the succinic part and variable ester moieties imply that each ASA molecule has its own characteristics, based on which applications could be developed