酯基有机硅季铵盐柔软整理剂的合成与表征

以硬脂酸和N-甲基二乙醇胺(MDEA)为原料进行酯化反应得到中间体硬脂酸甲基二乙醇胺酯,再与γ-氯丙基甲基二甲氧基硅烷季铵化反应制备二烷基酯基甲基二甲氧基硅烷季铵盐。通过单因素和正交实验,考察了反应温度、反应时间、反应物摩尔比及催化剂用量等对酯化反应的影响。酯化反应优化工艺条件:反应温度为180℃,反应时间为8 h,反应物摩尔比n(硬脂酸)∶n(MDEA)=1.6∶1.0,次磷酸催化剂质量分数为0.9%,转化率达98%;二甲基亚砜作为季铵化反应的溶剂。通过溴酚蓝显色反应以及红外光谱、1HNMR、ESI-MS分析中间体和产物的结构。测定了目标产物在298 K下的表面活性以及柔软性能,临界胶束质量浓度CMC为0.197 g/L,γCMC为24.25 mN/m,柔软性能优于同类市售产品。

Synthesis and Characterization of siloxane quaternary

A novel quaternary ammonium salt was obtained via quaternization reaction between γ-chloropropyl methyl dimethoxysilane and stearic ester of methyldiethanolamine synthesized from stearic acid and N-methyl diethanolamine(MDEA).The effects of some important parameters on the esterification reaction were investigated by orthogonal experiments,and the results show that the optimum reaction conditions were as follows:temperature 180 ℃,reaction time 8 h,n(stearic acid)∶ n(MDEA)=1.6 ∶ 1.0,catalyst mass fraction for hypophosphorous acid 0.9% of reactants.Under such optimum reaction conditions,the conversion rate of stearic acid could reach 98%.The intermediate and the final product were characterized by means of FTIR,1HNMR,ESI-MS,and the physicochemical properties were further investigated.The results show that CMC of the above quaternary ammonium salt was 0.197 g/L,the γCMC was 24.25 mN/m and its softening performance was superior to common commercial fabric softener.