CAJ | 학술논문

采用界面扩张流变技术研究了季铵盐偶联表面活性剂C12-(CH2)2-C12?2Br (Gemini12-2-12)及其与离子液体表面活性剂溴化1-十二烷基-3-甲基咪唑(C12mimBr)复配体系的动态界面张力、扩张流变性质和界面弛豫过程等，探讨了C12mimBr对C12mimBr/Gemini12-2-12混合体系界面性质的影响及C12mimBr对Gemini12-2-12界面聚集行为影响的机制。结果表明，随着离子液体表面活性剂的不断引入，体系界面吸附达到平衡所需的时间逐渐缩短，扩张模量和相角明显降低，界面吸附膜由粘弹性膜转变为近似纯弹性膜；同时，界面及其附近的弛豫过程也发生显著变化，慢弛豫过程消失，快弛豫过程占主导地位，且离子液体浓度越高，快弛豫的贡献越大。这些界面性质的变化主要归因于离子液体表面活性剂C12mimBr参与界面形成及两表面活性剂在界面竞争吸附的结果。少量离子液体表面活性剂C12mimBr的加入可以填补疏松的Gemini12-2-12界面上的空位，形成混合界面吸附膜。随着C12mimBr含量的增加，嵌入界面的C12mimBr分子数不断增多，导致界面上相互缠绕的Gemini12-2-12烷基链“解缠”，在体相和界面分子扩散交换的过程中“解缠”的Gemini12-2-12分子从界面上解吸回到体相，与此同时， C12mimBr分子相对较小的空间位阻及较强的疏水作用促使其优先扩散至界面进而取代Gemini12-2-12分子，最终界面几乎完全被C12mimBr分子所占据。
채용계면확장류변기술연구료계안염우련표면활성제C12-(CH2)2-C12?2Br (Gemini12-2-12)급기여리자액체표면활성제추화1-십이완기-3-갑기미서(C12mimBr)복배체계적동태계면장력、확장류변성질화계면이예과정등，탐토료C12mimBr대C12mimBr/Gemini12-2-12혼합체계계면성질적영향급C12mimBr대Gemini12-2-12계면취집행위영향적궤제。결과표명，수착리자액체표면활성제적불단인입，체계계면흡부체도평형소수적시간축점축단，확장모량화상각명현강저，계면흡부막유점탄성막전변위근사순탄성막；동시，계면급기부근적이예과정야발생현저변화，만이예과정소실，쾌이예과정점주도지위，차리자액체농도월고，쾌이예적공헌월대。저사계면성질적변화주요귀인우리자액체표면활성제C12mimBr삼여계면형성급량표면활성제재계면경쟁흡부적결과。소량리자액체표면활성제C12mimBr적가입가이전보소송적Gemini12-2-12계면상적공위，형성혼합계면흡부막。수착C12mimBr함량적증가，감입계면적C12mimBr분자수불단증다，도치계면상상호전요적Gemini12-2-12완기련“해전”，재체상화계면분자확산교환적과정중“해전”적Gemini12-2-12분자종계면상해흡회도체상，여차동시， C12mimBr분자상대교소적공간위조급교강적소수작용촉사기우선확산지계면진이취대Gemini12-2-12분자，최종계면궤호완전피C12mimBr분자소점거。
The dynamic interfacial tension, dilational rheological properties, and interfacial relaxation processes of quaternary ammonium Gemini surfactant C12-(CH2)2-C12?2Br (Gemini12-2-12) solutions and Gemini12-2-12/ionic liquid surfactant C12mimBr mixed systems at an air/water interface were investigated using an interfacial dilational rheology method at low frequencies (0.02-0.50 Hz). The effect of the C12mimBr on the interfacial properties of the Gemini12-2-12/C12mimBr mixed systems, and the mechanism responsible for the influence of C12mimBr on the aggregation behavior of the Gemini12-2-12 at the air/water interface, are discussed here. The experimental results showed that with increasing the amount of C12mimBr, the time required to achieve interfacial adsorption equilibrium for the mixed systems was reduced, the dilational moduli and phase angle in the mixed systems decreased, and the interfacial adsorption films were inclined to become elastic. Simultaneously, the relaxation processes at the interface or near the interface changed significantly, the slow relaxation process disappeared, and a fast relaxation process dominated the properties of the interfacial films.Moreover, the contribution of the fast relaxation process increased with increasing the concentration of C12mimBr. The abovementioned changes in the interfacial properties were mainly attributed to the participation of the C12mimBr in the formation of the interface, and the competitive adsorption of the two surfactants at the air/water interface. At lower concentrations of C12mimBr, the C12mimBr molecules fil ed the vacancies between the Gemini12-2-12 molecules when the Gemini12-2-12 molecules were loosely arranged at the interface, and mixed-adsorption films formed from C12mimBr and Gemini12-2-12 spread on the air/water interface. With increasing the concentration of C12mimBr, the alkyl chains of the Gemini12-2-12 molecules that were wrapped around each other at the air/water interface untangled, and the Gemini12-2-12 molecules underwent desorption from the interface. At the same time, C12mimBr molecules replaced Gemini12-2-12 molecules, because of their low steric hindrance and strong hydrophobic effects;ultimately, C12mimBr molecules almost entirely occupied the air/water interface.