Surfactants with an ester bond connecting the polar headgroup and the hydrophobic tail are common. They are easy to synthesize, they can often be made from natural raw materials and their biodegradation profile is generally good, partly due to lipase or esterase catalyzed breakdown of the ester bond in sewage plants. A labile ester bond in the molecule may cause problems, however. Surfactants are often formulated at relatively high pH and it is important that they remain intact for a given period of time. In this article we discuss alkaline hydrolysis of different types of ester-based surfactants—cationic, anionic and nonionic—and also of surfactant mixtures. We show that the ester bond in a surfactant has a different hydrolysis pattern than ester bonds in non-surface active uncharged molecules. Cationic ester-based surfactants are hydrolyzed rapidly while anionic and also nonionic ester-containing surfactants are relatively resistant to hydrolysis.

中文翻译：

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酯基表面活性剂：它们足够稳定吗？

具有连接极性头基和疏水尾的酯键的表面活性剂很常见。它们易于合成，通常可以由天然原料制成，并且它们的生物降解特性通常良好，部分原因是脂肪酶或酯酶在污水处理厂中催化了酯键的分解。然而，分子中不稳定的酯键可能会引起问题。表面活性剂通常在相对较高的 pH 值下配制，重要的是它们在给定的时间段内保持完好无损。在本文中，我们讨论了不同类型的酯基表面活性剂（阳离子、阴离子和非离子）以及表面活性剂混合物的碱水解。我们表明，表面活性剂中的酯键与非表面活性不带电分子中的酯键具有不同的水解模式。