Tween 80, also known as Polysorbate 80 is made from polyethoxylated sorbitan (chemical compounds derived from the dehydration of sugar alcohol), ethylene oxide and oleic acid, a fatty acid found in animal and vegetable fats. It is a safe, non-ionic emulsifier, an amber/golden-colored viscous liquid used as an emulsifier or surfactant in foods, medicines, skincare products, vaccines etc. It also acts as a surfactant in soaps and cosmetics and better suited to solubilizing true oils as compared to Tween 20.
The simple rule of thumb with these oils is, the higher the number, the stronger their potency for emulsifying water with heavier oils. For instance, if you need to blend essential or fragrance oils into water, Tween 20 would be all you need. If you are looking to emulsify a carrier oil into water, Tween 80 is sufficient for the job due to the higher rated polysorbate such. Hence, Tween 80 is often an ingredient in body washes, hair shampoos, lotions, creams, bath oils etc.
Disclaimer: Store at a cool room temperature.