PET plastic reduced the cost and weight of beverage containers. Originally, only glass and metal containers were suitable for storing carbonated drinks. Other plastics would bulge and break. However, PET plastic enabled plastic bottles suitable for carbonated drinks. Soon, it became used for all beverages.
In the 1960s, plastics engineer Wyeth questioned whether carbonated drinks could be stored in plastic bottles. Experimentation quickly the carbonation causes the bottles to expand and, sometimes, explode.
Wyeth worked for about a decade to find a plastic that could hold carbonated drinks, eventually innovating polyethylene-terephthalate (PET) plastic. He filed for patent protection in 1973. Eventually, PET bottles came to dominate the market.
Subsequently, Wyeth’s bottles have become an environmental mess. Eventually, in 2019, some bottlers are working to transition from PET bottles to more environmentally sustainable alternatives.