Polyethylene terephthalate (PET) bottles, which were introduced into the soft drinks industry in the 1970s as a safer and more convenient alternative to glass, are now firmly established as one of the main packages for beverages and other products. This basic guide covers the properties (particularly its gas-barrier properties that allow retention of carbon dioxide and nitrogen) and consumption of PET, and the history, manufacture (perform- and blow-moulding) and applications of PET bottles. The greater challenges faced by PET bottles used for beer (as opposed to soft drinks), the bottling conditions (filling temperature, pasteurization method, etc.), shelf-life expectations, and additional gas- and light-barrier requirements, and the steps being taken to overcome them (multi-layer bottles using modified polyamide or ethylene vinyl glycol barrier layers) are discussed. The potential of polyethylene naphthalate (PEN), which has superior performance but higher cost that PET, but may be blended with PET, is also discussed.
