两性表面活性剂与阴离子聚丙烯酰胺复配体系的抗盐性

Salt Resistance of Compound Systems for Amphoteric Surfactant and HPAM

通过单因素实验分析两性表面活性剂浓度、无机盐浓度及p H值对聚丙烯酰胺复配体系黏度的影响规律,应用SPSS软件对均匀实验结果进行非线性回归,得到复配体系黏度与聚合物浓度、两性表面活性剂浓度及无机盐浓度的定量关系式,进而理论分析了各因素对复配体系抗盐性的影响规律.结果表明,当两性表面活性剂的浓度低于临界缔合浓度(CAC)时,复配体系的黏度变化不大;当其浓度高于CAC后,随着浓度的增加,体系黏度急剧增大;当其浓度达到聚合物饱和浓度(PSP),复配体系黏度达到最大值;当再进一步加入表面活性剂时,聚集体间的网状结构将被破坏,从而使体系黏度逐渐降低;无机盐对复配体系的作用具有双重性,低浓度盐将促使体系黏度升高,中高浓度盐则会导致体系黏度降低;不同p H值条件下,复配体系的抗盐能力顺序为碱性(p H=11.4)>酸性(p H=2.8)>中性(p H=7).

Considering the salt sensitivity of HPAM and the salt resistance of amphoteric surfactant dodecyl dimethyl betaine, this work explored the effects of the surfactant and inorganic salt concentrations and pH values on the laws of viscosities of the compound systems by using the single factor experiments. The experimental results show that the viscosities of the systems change a little while the concentrations of the amphoteric surfactant are lower than the critical association concentration （CAC） ,but they increase sharply as the concentrations of the amphoteric surfactant increase above CAC, reach to a peak when the surfactant concentration equals to the polymer saturation concentration （PSP） and decrease with the network structure of the system broken by continuously adding the surfactant. Inorganic salt show a twofold effect on the viscosities of the compound systems, increasing within the low salt concentration and decreasing above the high concentration of salt. At different pH,the salt resistance is presented as alkaline （pH = 11.4） 〉 acidity （ pH = 2. 8） 〉 neutral（pH = 7）. In order to further explore the effect degree of the concentrations of polymer, amphoteric surfactant and inorganic salt for the system viscosities, this work has done nonlinear regression of the uniform experimental data by using SPSS software, gotten a quantitative relation of the compound system viscosity with three parameters and analyzed their effects on the salt resistance of the compound systems. The theoretical model shows that the polymer concentration is the most important factor, and the effects of the concentrations of amphoteric surfactant and inorganic salt on the system viscosities are similar to those of their single -factors.