Figure 2. Two-step synthesis of polysorbate 20: a) simultaneous anhydrization of sorbitol and esterification with lauric acid to form sorbitan laurate, and b) base catalyzed ethoxylation to form polysorbate 20

In practice, the latter route, shown in Figure 2, is employed commercially and depending on the exact process, may utilize either base catalysis as shown or a combination of acid and base catalysis.