Figure 1. Idealized chemical structure of polysorbate 20, where the average value of w + x + y + z = 20

The material generally conforms to the idealized structure shown in Figure 1—i.e., a four-arm, star-shaped oligomer of polyethylene glycol (PEG) grown from a sorbitan core with a laurate ester end-capping one of the PEG arms.