阳离子型偶氮类Gemini表面活性剂的合成及其复配体系性能研究

发布时间：2019-01-07 11:01

【摘要】：Gemini型表面活性剂一般具有双个亲水基和双个亲油基,其表面活性通常比传统型表面活性剂高出数个数量级。偶氮苯化合物是一类具有顺反异构体的化合物。本文以一种光敏型的偶氮类阳离子型Gemini表面活性剂(AzoBr)为模型化合物,研究了它的制备方法,通过红外光谱和核磁氢谱对其进行了结构表征,并用紫外光谱验证了其光致顺反异构化的特性。同时,测定了该表面活性剂的表面活性。研究结果表明,该表面活性剂具有较低的临界胶束浓度(cmc),表面活性可以通过紫外光的照射进行调控。本文研究了此类表面活性剂的光泡沫性能,利用小弦周期振荡法和弛豫法等研究了此类表面活性剂的在水/空气界面的扩张粘弹性,探索了扩张粘弹性与泡沫稳定性之间的关系。结果表明:AzoBr具有较好的发泡能力,泡沫较为稳定;在紫外光照射后,泡沫稳定性降低。扩张粘弹性的结果显示,在紫外光照射后表面活性剂的模量降低,是造成泡沫稳定性下降的主要原因。该表面活性剂在水/空气界面附近存在多个弛豫过程,且紫外光照射前后弛豫过程有所不同。为了扩宽该表面活性剂的应用范畴,本文探索了该表面活性剂复配体系的相关溶液性质,研究了AzoBr与硬脂酸复配体系的性质,通过相关系数的计算得到了最佳复配比,并且测定了在紫外光照射前后复配体系的表面活性、泡沫稳定性以及流变性能。结果表明,复配体系有较好的正协同效应,最低表面张力和临界胶束浓度均低于单一体系的相应参数。我们还研究了复配体系的流变性质,该复配体系具有屈服应力值。最后,我们利用AzoBr对石英进行了纯矿物浮选试验,通过测定接触角、上浮率、Zeta电位及吸附量等方法研究了浮选机理。结果表明,该光敏型表面活性剂对石英具有很好的捕收能力。
[Abstract]:Gemini surfactants generally have two hydrophilic groups and two hydrophilic groups, and their surface activity is usually several orders of magnitude higher than that of traditional surfactants. Azobenzene compounds are a class of compounds with cis-trans isomers. In this paper, an azo cationic Gemini surfactant (AzoBr) of Guang Min type was used as a model compound, and its preparation method was studied. Its structure was characterized by IR and NMR spectra. The photoisomerization of cis-trans isomerization was verified by UV spectra. At the same time, the surface activity of the surfactant was determined. The results show that the surfactant has lower critical micelle concentration (cmc),) surface activity can be controlled by UV irradiation. In this paper, the photofoam properties of the surfactants are studied. The viscoelasticity of the surfactants at the water / air interface is studied by using the small chord periodic oscillation method and relaxation method. The relationship between expanded viscoelasticity and foam stability is explored. The results show that AzoBr has good foaming ability and the foam is stable, and the foam stability decreases after UV irradiation. The results of expanded viscoelasticity show that the decrease of surfactant modulus after UV irradiation is the main reason for the decrease of foam stability. There are several relaxation processes near the water / air interface, and the relaxation process is different before and after UV irradiation. In order to widen the scope of application of the surfactant, the properties of the surfactant complex system were studied in this paper, and the properties of the mixture system of AzoBr and stearic acid were studied. The optimum blending ratio was obtained by calculating the correlation coefficient. The surface activity, foam stability and rheological properties of the composite system were determined before and after UV irradiation. The results show that the compound system has a good positive synergistic effect and the minimum surface tension and the critical micelle concentration are lower than the corresponding parameters of the single system. We also studied the rheological properties of the complex system, which has yield stress value. Finally, the flotation mechanism of quartz was studied by measuring contact angle, floatation rate, Zeta potential and adsorption capacity by using AzoBr. The results show that the Guang Min surfactant has good collecting ability to quartz.
【学位授予单位】：贵州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O647.2

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