摘要：以芘为荧光探针，二苯甲酮为猝灭剂，采用稳态荧光探针法测定了聚氧乙烯（21）硬脂基醚（Brij721）表面活性剂增溶芘后的稳态荧光光谱，建立了Brij721非离子表面活性剂的临界胶束浓度（CMC）和临界胶束聚集数（Nm）的测试方法。根据I322/I337与Brij721浓度变化的关系，可得到Brij721的临界胶束浓度为3.45×10-6mol/L。确定荧光探针芘的适宜浓度Cp为6×10-7mol/L，猝灭剂的适宜浓度CQ范围取为0.002～0.003mmol/L，表面活性剂溶液浓度为3~12倍CMC时，胶束聚集数(N)随表面活性剂浓度增大而线性增大，并用线性拟合作图法得到Brij721的临界胶束聚集数为9。同时，外部添加的试剂如无机盐、乙醇均影响其临界胶束浓度。7833
关键字：荧光探针法；临界胶束浓度；临界胶束聚集数；脂肪醇聚氧乙烯醚
Determination of Critical Micelle Concentration (CMC) of Nonionic Surfactant of Fatty Alcohol-polyoxyethylene Ether by Steady-State Fluorescence Probe Method
Abstract: Taken the pyrene as the fluorescence probe and diphenyl ketone as quencher, the steady-state fluorescence spectrum of Polyoxyethylene (21) stearyl ether (Brij721) surfactant was determined by fluorescence probe method. A sensitive method for determining critical micelle concentration (CMC) and critical micelle aggregation number (Nm) of Brij721 surfactant was established. According to the change of fluorescence intensity ratio of pyrene I322/ I337 with the change of surfactant concentration of aqueous solution, CMC value for Brij721 was 3.45×10-6 mol/L. Ensure the proper concentration of fluorescence probe is 6×10-7mol/L, the proper concentration range of quencher is 0.002~0.003mmol/L, the aggregation number (N) increases linearly with the increase of Brij721 concentration in the range of 3~12 times of CMC and Nm which is 9 can be extrapolated from N-C fitting curve. In addition, the externally added reagents such as salts and ethanol also influence CMC.
Key Words: fluorescence probe method; critical micelle concentration; micelle aggregation number; fatty alcohol-polyoxyethylene ether
目 录
1 前言 1
1.1 脂肪醇聚氧乙烯醚非离子表面活性剂研究现状 1
1.2 脂肪醇聚氧乙烯醚非离子表面活性剂的应用 1
1.3 表面活性剂的临界胶束浓度概念 1
1.3.1 表面活性剂胶束化作用的定义 2
1.3.2 临界胶束浓度的作用及意义 2
1.4 关于临界胶束浓度的测定方法 2
1.4.1 表面张力法 2
1.4.2 电导率法 3
1.4.3 染色法 3
1.4.4 浊度法 3
1.4.5 共振光散射法 3
1.4.6 超滤法 4
1.4.7 吸附伏安法 4
1.4.8 紫外分光光度法 4
1.4.9 微分吸附计时电位法 4
1.4.10 荧光探针法 5
1.5 影响临界胶束浓度的因素 5
1.6 胶束聚集数及其测定方法 6
1.7 本课题研究的目的和意义 6
2 实验部分 7
2.1 实验原料 7
2.2 实验仪器与设备 7
2.3 实验溶液的配制 7
2.3.1 测定CMC所需各标准溶液的配制 7
2.3.2 确定合适猝灭剂浓度所需各溶液的配制 10
2.3.3 测定临界胶束聚集数所需溶液的配制 11
2.4 测定方法 11
2.4.1 不同浓度Brij721溶液中芘的激发光谱测定 11
2.4.2 不同浓度Brij721溶液中芘的发射光谱测定 11 荧光探针法测定脂肪醇聚氧乙烯醚非离子表面活性剂的临界胶束浓度:http://www.youerw.com/huaxue/lunwen_5932.html