[2] The process was developed at the Ludwigshafen laboratories of IG Farben by Conrad Schöller and Max Wittwer [de] during the 1930s.
The reaction typically proceeds by blowing ethylene oxide through the alcohol at 180 °C and under 1-2 bar of pressure, with potassium hydroxide (KOH) serving as a catalyst.
[5] The process is highly exothermic (ΔH = -92 kJ/mol of ethylene oxide reacted) and requires careful control to avoid a potentially disastrous thermal runaway.
Both reactions are normally performed in the same reactor and may be run simultaneously to give a random polymer, or in alternation to obtain block copolymers such as poloxamers.
Ethoxylated fatty alcohols are often converted to the corresponding organosulfates, which can be easily deprotonated to give anionic surfactants such as sodium laureth sulfate.
It's essential to consider the specific range of ethoxylation (number of ethylene oxide units) to optimize the method further.
[14] Examples synthesized on an industrial scale include octyl phenol ethoxylate, polysorbate 80 and poloxamers.
[15][page needed] They feature both lipophilic tails, indicated by the alkyl group abbreviation, R, and relatively polar headgroups, represented by the formula R(OC2H4)nOH.
[16][page needed] A high-volume example of these is sodium laureth sulfate a foaming agent in shampoos and liquid soaps, as well as industrial detergents.
[citation needed] Alcohol ethoxylates are not observed to be mutagenic, carcinogenic, or skin sensitizers, nor cause reproductive or developmental effects.
[19] AEs are usually released down the drain, where they may be adsorbed into solids and biodegrade through anaerobic processes, with ~28–58% degraded in the sewer.
[20] If released into surface waters, sediment or soil, AEs will degrade through aerobic and anaerobic processes or be taken up by plants and animals.
Flow-through laboratory tests in a terminal pool of AES with mollusks found the NOEC of a snail, Goniobasis and the Asian clam, Corbicula to be greater than 730 ug/L.
[16] A 2022 study revealed the expression of genes involved in cell survival, epithelial barrier, cytokine signaling, and metabolism were altered by rinse aid in concentrations used in professional dishwashers.
The alcohol ethoxylates present in the rinse aid were identified as the culprit component causing the epithelial inflammation and barrier damage.