It depends on the glue type, but a lack of air inside the bottle is key. PVA glue contains long molecules, called polymers, and water. When you squeeze the glue out, the water evaporates to the air, leaving just sticky polymers.
Super glue, on the other hand, contains a chemical that hardens as soon as it hits water vapour in the atmosphere.
In short, PVA glue doesn’t stick to its bottle because water is trapped inside while super glue’s container keeps water out.
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Dr Emma Davies is a science writer and editor with a PhD in food chemistry from the University of Leeds. She writes about all aspects of chemistry, from food and the environment to toxicology and regulatory science.