Bis-PEG/PPG-16/16 PEG/PPG-16/16 Dimethicone is a derivative of Dimethicone (q.v.) containing an alkoxylated side chain with an average of 16 moles of ethylene oxide and 16 moles of propylene oxide, and end-blocked with an average of 16 moles of ethylene oxide and 16 moles of propylene oxide.