摘要
为了研究三直链烷基苯磺酸钠的分子结构与表面活性之间的关系,以对二氯苯为原料,经交叉耦合反应、傅-克酰基化反应、黄鸣龙还原反应、磺化反应以及中和反应等步骤,合成了5种不同烷基链长的三直链烷基苯磺酸钠,产物的收率为45%～53%,用两相滴定法测定产物的纯度均大于99.5%,并用核磁共振氢谱和碳谱对产物进行了结构鉴定.用Wilhelmy-Plate法测定了三直链烷基苯磺酸钠水溶液的表面性质,发现直链烷基苯磺酸钠疏水链碳数增加,临界胶束浓度CMC减小;相同疏水碳原子的化合物,短侧链碳数少的化合物CMC低;长侧链碳数保持不变,两个短侧链碳数由4个增加至8个,临界胶束浓度下的表面张力γcmc由32.44 mN/m降低至28.97 mN/m;而短侧链碳数保持不变,长侧链碳数由7个增加至11个,γcmc变化不明显.
In order to study the correlation between structure and surface activity, five kinds of sodium n-trialkylbenzene sulfonates with different length of alkyl chains were synthesized from p-dichlorobenzene through five-step process, including cross-coupling reaction, Friedel-Crafts alkylation reaction, Huang Min-long reduction reaction, sulfonation and neutralization reactions. The product yields were 45%-53%. The purity of the products were all above 99.5% determined by the two-phase titration method. Their structures were identified by 1H NMR and 13C NMR. The surface activity properties of the sodium n-trialkylbenzene sulfonate tested by Wilhelmy-plate method. It is shown that the carbon number of the hydrophobic side chains of the sulfonates molecule increased, but CMC (the critical micelle concentration) decreased. The compound with smaller carbon number of short side chain held the lower CMC. γcmc (the interfacial tension at CMC) decreased from 32.44 mN/m to 28.97 mN/m with the increasing of the carbon number of two short side chains from 4 to 8 and the constant carbon number of long side chain, but the carbon number's increase of long side chain from 7 to 11 produced no obvious influence on γcmc with the unvaried carbon number of short side chains.
出处
《石油化工高等学校学报》
EI
CAS
2005年第3期20-24,29,共6页
Journal of Petrochemical Universities
基金
国家重点基础研究发展计划资助项目(G19990225)。
关键词
三直链烷基苯磺酸钠
三直链烷基笨
双直链烷基苯
合成
表面活性
Sodium n - trialkylbenzene sulfonates
n - trialkylbenzene
n - dialkylbenzene
Synthesis
Surface activity
