The main purpose of this work is to investigate the effect of PO groups on the wetting properties of surfactant solutions on polytetrafluoroethylene (PTFE) surfaces. The surface tension and contact angle at the PTFE surface were measured for the extended surfactants dodecyl (polyoxyisopropyl)₄ sulphate (L-C₁₂PO₄S) and dodecyl (polyoxyisopropyl)₁₁ sulphate (L-C₁₂PO₁₁S). The results show that PO groups can significantly reduce the critical micelle concentration (CMC) for the surfactants. The contact angles for L-C₁₂PO₄S and L-C₁₂PO₁₁S remain almost constant below the CMC and decrease significantly above the CMC. L-C₁₂PO₄S and L-C₁₂PO₁₁S show a linear relationship between the surface tension and adhesion tension. It is noteworthy that the solid–liquid interfacial tension of the surfactant decreases more significantly above the CMC. This implies that the adsorption behaviour of surfactants is different below and above the CMC. Below the CMC, surfactants are adsorbed at the PTFE surface through hydrophobic chains and form a loose film. Compared to the anionic surfactant SDS, the introduction of the PO group leads to unique adsorption behaviour for the surfactant. The extended surfactant molecules form a saturated adsorption film at the air-liquid interface but continue to adsorb and form semi-micelles at the solid–liquid interface above the CMC.

这项工作的主要目的是研究 PO 基团对聚四氟乙烯 (PTFE) 表面表面活性剂溶液润湿性能的影响。对于扩展的表面活性剂十二烷基（聚氧异丙基）₄硫酸盐（LC ₁₂ PO ₄ S）和十二烷基（聚氧异丙基）₁₁硫酸盐（LC ₁₂ PO ₁₁ S），测量了 PTFE 表面的表面张力和接触角。结果表明，PO 基团可以显着降低表面活性剂的临界胶束浓度 (CMC)。LC ₁₂ PO ₄ S 和 LC ₁₂ PO ₁₁的接触角S 在 CMC 之下几乎保持不变，而在 CMC 之上则显着降低。LC ₁₂ PO ₄ S 和 LC ₁₂ PO ₁₁S显示表面张力和粘附张力之间的线性关系。值得注意的是，表面活性剂的固液界面张力在 CMC 以上下降得更明显。这意味着表面活性剂的吸附行为在 CMC 之下和之上是不同的。在 CMC 下方，表面活性剂通过疏水链吸附在 PTFE 表面并形成松散的薄膜。与阴离子表面活性剂 SDS 相比，PO 基团的引入导致表面活性剂具有独特的吸附行为。扩展的表面活性剂分子在气-液界面形成饱和吸附膜，但在CMC上方的固-液界面继续吸附并形成半胶束。