两性木质素分散剂的合成及表征

摘要

Calcium lignosulfonate was sulfonated using sodium bisulfite as sulfonating agent. N-(2,3-ep-oxypropyl) hexadecyl dimethyl ammonium chloride intermediate was synthesized by N,N-dimethyl hexadecyl-amine and epichlorohydrin. The lignin amphoteric surfactant (LAS) was prepared through hydroxyl alkyation reaction by the N-(2,3-epoxypropyl) hexadecyl dimethyl ammonium chloride and sulphonated calcium lignosul-phonate (SL) in the presence of tetrabutylammonium bromide catalyst. Through the orthogonal experiment,the optimal sulphonating conditions were determined: 2.0 g of sulfonating agent,reacted at 95 ℃ for 8 h,the relative degree of sulfonation of calcium lignosulfonate was 1.284. The optimal synthesis conditions of LAS were: m(SL):m(intermediate)=1:2.5,the dosage of phase transfer catalyst was 0.4%(on the total mass),pH=9,reacted at 55 ℃ for 3 h,the N mass fraction of product was 2.19%. The structure of the target product was characterized by FTIR spectrum and UV. The contact angle and surface tension was tested and showed that the dispersion of LAS became better distinctly.%以亚硫酸氢钠为磺化剂,对木质素磺酸钙进行磺化；以十六烷基二甲基叔胺、环氧氯丙烷为原料,合成了中间体(2,3-环氧丙基)十六烷基二甲基氯化铵；再以四丁基溴化铵为相转移催化剂,与磺化木质素磺酸钙(SL)的酚羟基反应,合成了木质素两性表面活性剂(LAS).通过正交试验确定了最佳磺化条件:磺化剂用量2.0 g,反应时间8h,反应温度95℃,木质素磺酸钙的相对磺化度为1.284;LAS的最佳合成条件:m(SL)∶m(中间体)=1∶2.5,相转移催化剂用量为总质量的0.4％,pH=9,55℃反应3h,产物中的含氮量为2.19％.通过傅里叶变换红外光谱、紫外光谱证实了目标产物结构；并进行接触角和表面张力测试,结果表明,LAS的分散性有明显改善.