The main differences between PET and PETG bottles are:
Material composition – PET is made from polyethylene terephthalate, while PETG contains glycol modifiers that make it more flexible and impact-resistant than standard PET.
Strength and stiffness – PET is stronger and stiffer than PETG. PET retains its shape better but is more brittle. PETG is tougher and more impact-resistant than PET.
Clarity – PET tends to be clearer than PETG, which has a slight haze. This makes PET preferred for water and beverage bottles.
Heat deflection – PET softens at a higher temperature than PETG, around 67°C vs 55°C. PETG can withstand somewhat higher temperatures than PET before deforming.
Molding properties – PETG is easier to process and mold than PET as it has a wider temperature window. PETG lends itself better to blow molding complex bottle shapes.
Recyclability – Both PET and PETG bottles can be recycled, but PET is recycled more widely as the manufacturing process is more standardized.
Food contact approval – PET is generally considered safer for food and beverage containers due to its prevalence and historical use. PETG approval depends on the region and intended contents.
So in summary, PET is typically used for clear water bottles due to its clarity, strength, and food safety approvals, while PETG is utilized more for tough reusable bottles due to its flexibility and moldability.
