Effect of Chemical Structure of Quaternary Ammonium Salt-type Cationic Surfactants and Temperature on Aggregate Size

摘要

Effect of temperature on drag reduction behavior of quaternary ammonium salt cationic surfactant solutions with sodium salicylate (NaSal) was investigated in terms of 1) alkyl chain length and 2) number of 2-hydroxyethyl groups. Characterization concerning DR effect, pressure loss, first normal stress differce (N_1) and aggregate size for NaSal/cationics solutions were carried out. NaSal/cations solutions containing above 40 nm-sized aggregation had a large DR effect ranged from 65-80%. However, the effect suddenly changed to 5-7% below 30 nm in agregate size. The aggregate size apparently plays an important role in DR effect.