当前位置: X-MOL 学术J. Surfactants Deterg. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Viscoelastic Behavior of Synthesized Liquid Soaps and Surface Activity Properties of Surfactants
Journal of Surfactants and Detergents ( IF 1.6 ) Pub Date : 2020-06-23 , DOI: 10.1002/jsde.12444
Amra Bratovcic 1 , Sanela Nazdrajic 2
Affiliation  

In the present work, a rheological study of liquid soaps prepared from different mixture of surfactants as a function of surfactant type and concentration was performed. The curves of shear stress vs. shear rate and viscosity vs. shear rate were recorded at constant temperature, 294 ± 0.1 K. The surface activity properties were also studied. The results of the study showed that values of surface tension, γ, were in the range 31–40 mN m−1 and the critical micelle concentration (CMC), was of the order 10−4 mol L−1. The calculated maximum surface excess, Γmax, varied from 2.40 to 3.66 μmol m−2, while minimum area per molecule, Amin, varied from 41.1 (for amphoterics) to 81.4 Å2 (for nonionic surfactants). The standard free energy of micellization,urn:x-wiley:10973958:media:jsde12444:jsde12444-math-0001 −29.8 and −29.3 kJ mol−1 for anionic and amphoteric surfactants, respectively, were while values for nonionic surfactants varied between −31.8 and − 30.3 kJ mol−1. The free energy of adsorption, urn:x-wiley:10973958:media:jsde12444:jsde12444-math-0002 was the lowest for amphoteric surfactants (−37.9 kJ mol−1), followed by anionics (−40.4 kJ mol−1) and nonionics (−43.34 to −46.84 kJ mol−1), indicating that micellization process is spontaneous in the examined medium. The synthetized liquid soaps show pseudoplastic behavior and they achieved pipe flow. The results of this research indicate that flow behavior was affected significantly by the ionic charge of the surfactant and the ionic strength of the formulation, suggesting that the flow behavior could be changed by manipulating the choice of the surfactant and salinity. The pH value of all liquid soaps examined were weakly acidic, in the range of 5.0–6.4.

中文翻译:

合成液体皂的粘弹性行为和表面活性剂的表面活性

在当前的工作中,对由不同表面活性剂混合物制备的液体肥皂的流变学进行了研究,该皂液是表面活性剂类型和浓度的函数。在294±0.1 K的恒温下记录了剪切应力剪切速率,粘度剪切速率的关系曲线。还研究了表面活性特性。研究结果表明,表面张力γ的值在31–40 mN m -1范围内,临界胶束浓度(CMC)在10 -4 mol L -1左右。计算出的最大表面过剩,Γ最大,从2.40变化至3.66微摩尔米-2,每分子而最小面积,A分钟,从41.1(对于两性表面活性剂)变化到81.4埃2(对于非离子表面活性剂)。阴离子和两性表面活性剂的胶束化标准自由能分别为缸:x-wiley:10973958:media:jsde12444:jsde12444-math-0001-29.8和-29.3 kJ mol -1,而非离子表面活性剂的胶束化标准自由能为-31.8和-30.3 kJ mol -1缸:x-wiley:10973958:media:jsde12444:jsde12444-math-0002两性表面活性剂的吸附自由能最低(-37.9 kJ mol -1),其次是阴离子表面活性剂(-40.4 kJ mol -1)和非离子表面活性剂(-43.34至-46.84 kJ mol -1)),表明胶束化过程在所检查的培养基中是自发的。合成的液体肥皂显示出假塑性行为,并实现了管道流动。该研究结果表明,表面活性剂的离子电荷和制剂的离子强度显着影响流动性能,这表明可以通过控制表面活性剂和盐度的选择来改变流动性能。检查的所有液体肥皂的pH值均为弱酸性,范围为5.0-6.4。
更新日期:2020-06-23
down
wechat
bug