Octadecyl Dimethyl Hydroxyethyl Ammonium Bromide Synthesis And Properties Of

A new type cationic surfucant–octadecylmethyldihydroxyethyl ammonium bromide(OMDAB)was syhthesized from N-Methyldiethanolamine and bromododecane in this study. The structure of the product was characterized with elemental analysis, IR and ¹H NMR.Through RSM, the mathematical relational model between conversion rate and factors was established, and the microwave synthesis technique of octadecylmethyldihydroxyethyl ammonium bromide was optimized. The results showed that the most suitable condition for the reaction were as follow as: the concentration of reactants was 1.87 mol·L^-1, the microwave power was 570W,the reaction time was 25min,and the conversion reached up to 95.30%.Compared with traditional method,the synthesized time was only 4.63%.The octadecylmethyldihydroxyethyl ammonium bromide was synthesized through solvent-free method,and the most suitable condition were as follow as: the temperature was 100℃,the reaction time was 180min,the mole ratio was 1:1,and the conversion reached up to 95.02%. According to the best reaction conditions amplification experiment was made in 2L Glass reactor.The amplify of synihesis course and factors were studied,then the corresponding solutions were put forward.Through determination and study on the surface properties and application performance of OMDAB, the CMC was 3.18×10^-5mol·L^-1, surface tension was 22.7N·m^-1, Krafft Point was below 0℃and melting point of the product was 120.02¹20.82℃. At the same time, it showed good solubilization and deuto-wetting property of the surfactant. Its emulsification property, foaming property, softening property and sterilization effect were also quite well; besides the effect on fabric whiteness was lower.The surface chemical properties, water solubility and synergy were studied on the mixed systems based on OMDAB and sodium dodecyl sulfate(SDS), OMDAB and dodecylbenzenesulfonate acid sodium (LAS), OMDAB and betaine.The results showed that mixed solution is stable, and surface chemical properties remarkably enhanced in a certain range of concentration. Determined by the application of the complex system performance, complex system, part of the application performance than a single system, different degrees of increase, which was the role of synergistic effects.