The properties of mixtures of poly (ethylene oxide) (PEO) and mixed micelles formed from sodium cholate (NaC) and sodium dodecyl sulfate (SDS) in tris/HCl buffered solutions at pH 9.00 were investigated by measuring t...The properties of mixtures of poly (ethylene oxide) (PEO) and mixed micelles formed from sodium cholate (NaC) and sodium dodecyl sulfate (SDS) in tris/HCl buffered solutions at pH 9.00 were investigated by measuring the mean surface tension. The variation in the superficial tension as a function of the time after formation of solutions containing PEO and NaC was characterized by monitoring the time required for the system to reach equilibrium between the micellar and aqueous phases. These results could serve as a reference for the minimum aging time required for solutions before any surface tension measurements can be performed.展开更多
文摘以正己醇作为引发剂,分别与环氧乙烷和环氧丙烷发生聚合,再以气体三氧化硫进行硫酸化反应,合成了正己醇聚氧乙烯醚硫酸钠(HE3S)以及正己醇聚氧丙烯醚硫酸钠(HP3S)2种阴非离子型表面活性剂。采用FTIR和1H NMR技术对表面活性剂结构进行了表征。通过平衡表面张力、动态表面张力和动态接触角研究了其水溶液的表面活性。实验结果表明,HE3S和HP3S在298 K下的临界胶束浓度分别为58.36 mmol/L和53.84 mmol/L,最低表面张力分别为33.91 m N/m和33.29 m N/m;由动态表面张力计算出的扩散系数,可知两种表面活性剂在水溶液中的吸附机理均属于混合动力控制吸附;当溶液浓度为150 mmol/L时,HE3S和HP3S的水溶液液滴在石蜡膜上可以短时间内快速铺展,其最低接触角分别达到64.5°和55.9°。
文摘The properties of mixtures of poly (ethylene oxide) (PEO) and mixed micelles formed from sodium cholate (NaC) and sodium dodecyl sulfate (SDS) in tris/HCl buffered solutions at pH 9.00 were investigated by measuring the mean surface tension. The variation in the superficial tension as a function of the time after formation of solutions containing PEO and NaC was characterized by monitoring the time required for the system to reach equilibrium between the micellar and aqueous phases. These results could serve as a reference for the minimum aging time required for solutions before any surface tension measurements can be performed.