Synthesis and performance study of cationic surfactants containing different quantities of hydroxyl.

Three hydroxyl-containing cationic surfactants are synthesized and characterized by FTIR and HNMR, and their thermal stability is tested and analyzed. The surface activity, adsorption and aggregation behavior of the synthesized target product were investigated by testing its contact angle, static surface tension and dynamic surface tension. As the number of hydroxyl groups increases, the maximum adsorption amount ( ) of molecules at the interface gradually decreases, and the minimum area occupied by each molecule ( ) increases, suggesting that the introduction of hydroxyl groups weakens the interfacial accumulation ability between molecules and increases the hydrophilicity.

The influence of hydrogen bonding on the structure of organic-inorganic hybrid catalysts and its application in the solvent-free epoxidation of α-olefins.

In this study, two types of catalysts were prepared by the combination of gemini quaternary ammonium salt with two distinct species of phosphotungstic acid. Catalysts prepared by the Wells-Dawson type of phosphotungstic acid and Keggin-type phosphotungstic acid both exhibited dual-phase catalytic behavior, demonstrating both heterogeneous and homogeneous catalytic activities. In comparison to the catalyst prepared by the Keggin-type phosphotungstic acid, due to the higher size of Wells-Dawson type of phosphotungstic acid, hydrogen bonding could not effectively affect the catalyst prepared by HPWO.