From the children studying in the school to the people who work in the office, every person uses glue. And this question often revolves in our mind that, why does not the glue stick to the inside of the bottle in which it is kept. As soon as we put it on something, it gets stiff in a while, and sticks on that thing on which we put it, but why not in the bottle.
Is it a magic trick? Or the bottle, in which the glue fills, made of any special kind of metal? What is the exact reason behind this mystery?
So it is not because of magic, but because of science. And what if told you that, the real reason behind this mystery is water? Yes water, water is the thing that which is the difference between glue adhesive and hardening.
Usually, the glue we use is white glue, which is used to paste paper, envelopes and other normal things. The white glue is made of various chemicals called polymers. These polymers are long strands that are either sticky or stretchy. To make the best glue, the glue manufacturer finds and uses the exact combination of the sticky and stretchy polymer. Water also mixes in white glue. Water serves as a solvent, which keeps the glue liquid until you want it to stick.
And whenever you put glue on any piece of paper or other things, then the water that acts as a solvent comes into contact with the air. Because of that that the water starting evaporates, means it starts turning from liquid to gas and in a few milliseconds, the water present in the glue becomes completely evaporated. And as soon as the water is evaporated, the gum completely dries up and becomes stiff. Only the sticky polymers in the gum survive, which keeps things together. This process is known as mechanical adhesion.
Now few of us might be thinking that why doesn’t glue stick to the inside of the bottle? This is because when the glue is inside a bottle, there is not enough air inside the bottle so that the water can come into contact with air and evaporate. The bottle keeps the gum away from the air so that the glue remains liquid.
Now, what about super glue, Does the same process applicable on superglue? So the answer is no. The process and chemical used in both the glue are different, yes but one thing common and that is the effect of water. However, the water effects both the glue but the effect of water on both sides are different.
Often you may have noticed that super glue dries more quickly in its container compared to the common white glue. The way of working of super glue is quite different from the common white glue. Where the white glue made of with polymer, the superglue is made of a chemical called cyanoacrylate. Cyanoacrylate chemical binds things together when reacting with water vapor in the air. This process is called chemical adhesion. No matter how dry the air is, there is always some water vapor in the air.
To keep the super glue from drying out, the container in which super glue filled must be kept tightly sealed to prevent water vapor from seeping in and reacting with the glue, If not, then the super glue will be dried very soon and very easily, by which it will become useless.
So it would not be wrong to say that water is the thing which plays an important role in making both the glue worthy or inefficient. With white glue, you need the bottle to keep the water in the glue so the glue won’t be dried out and it remains sticky. And in Superglue containers, keep water out to prevent the chemical reaction that will dry the glue.
So now you got your answer that why does not the glue stick to the inside of the bottle. Hopefully, now you may have understood the science behind this childhood mystery, still, if you are confused that why does not the glue stick to the inside of the bottle or if you have any question about this, so you can ask us in the comments section.