Evaluation and application of surfactants synthesized from asphalt components

The synthesis, characterization, surface activity and applications of nonionic surfactants derived from the asphalt components (maltenes M) are presented. These compounds were synthesized by the sulfonation of (maltene), then the prepared maltene sulfonic acid (MS) was reacted with hexadecylamine giving maltene sulfonamide product (A) which undergoes an alkali-catalyzed ethoxylation at (135–150 °C). Several surfactants (M-10 to M-40) were formed with different ethylene oxide units (from 10 up to 40) and were characterized by molecular weight determinations, elemental analyses and FTIR analysis. Surface tension, as a function of concentration of the surfactants in the aqueous media, was measured at 25 °C. From these measurements, the critical micelle concentration (CMC), the maximum surface excess concentration (Гmax), Minimum area per molecule (Amin), effectiveness of surface reduction (ПCMC) and the efficiency (pC20) were calculated. The prepared surfactants were applied as emulsifying agents for making asphalt emulsions. Storage stability, (Saybolt Furol) viscosity, settlement (water content difference %), coating ability and water resistance were measured. The results indicated that M-20 (maltene sulfonamide ethoxylated with 20 units of ethylene oxides) gives a maximum stability.