What kind of plastic is a soft drink bottle cap?
Soft drink bottle caps are usually made from HDPE (High-Density Polyethylene) or PP (Polypropylene) plastic, depending on the manufacturer. Specifically:
1. HDPE (High-Density Polyethylene)
Advantages:
Good resistance, hard to break.
Waterproof, resistant to mild chemicals.
Safe for food.
Application: Common for soft drink, mineral water, and carbonated soft drink bottle caps because they can withstand pressure inside the bottle well.
2. PP (Polypropylene)
Advantages:
Mechanical durability, good heat resistance.
Easy to create threads, easy to open and close.
Also food safe.
Application: Some soft drink bottles use PP as the cap, especially if the bottle has a special design or requires easier opening and closing.
👉 In addition, the seal ring inside the bottle cap is usually soft PE or TPE lining to ensure tightness and no air leakage (especially with carbonated drinks).