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Why doesn't Elmer glue stick to its bottle?
Answer 1:

This is a really good question. It reminds me of an experiment Feynman carried out when he was a student in college. He asked the question:
If you make Jello but NEVER STOP STIRRING IT, WILL IT COAGULATE?

I think simple questions like this show that someone may be headed for a career in science because they speak of a basic curiosity about the world and because although EVERYONE uses Elmers glue all the time FEW PEOPLE stop to ponder the Whys!!!

Anyway, I am not totally certain but I think it has to due with drying. When you put a layer of Elmers glue on something it is a THIN layer...and a thin layer has a LOT of surface area. This surface area allows the glue to lose water i.e. dry out... and the white stuff becomes sticky and eventually hardens and bonds. In a bottle of the stuff, the surface area to volume ratio is relatively small... and so also the bottle is closed and so the glue cannot lose the excess water, and so it stays liquid. A way to test this is to put some in a dish and see if a thin SKIN of hardened glue forms. The hypothesis I have proposed would say that a skin should form at the top where the glue is adjacent to air... and to further test you could set up a fan and gently blow across the surface... the skin should form faster if I am correct.

So try an EXPERIMENT. SCIENCE IS THE BELIEF IN THE IGNORANCE OF EXPERTS...conduct an experiment and let Mother Nature guide you to the truth!!!!


Answer 2:

It contains a solvent (water) which keeps the glue a liquid.After the solvent evaporates, the remaining polymer glue hardens. If you leave the cap off the bottle, and the water evaporates, Elmer's will stick to the bottle.


Answer 3:

Elmers glue does not stick to its bottle because it doesnt bond two items together until it is dry. You may have noticed that if you glue two pieces of paper together, you can still move the papers while the glue is really wet. As the glue dries, it becomes harder to move the papers until the glue is completely dry and the papers are stuck together. This is the same for the bottle- when the glue is wet, it can flow freely inside the bottle and does not stick to the sides. The reason this works is because of the chemical composition of the glue. When it is liquid the glue can move and flow like a fluid, but as it dries the molecules in the glue become locked and stick your surfaces together.Thank you for your question!


Answer 4:

Glue is a solid that is dissolved in a solvent. As the solvent evaporates, the solid sets. If the solution is not exposed to the air, the solvent will not evaporate, and the glue will remain fluid. Glue will stick to the bottle if exposed to the air.



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