Grades K–2 · Everyday Life
How does a glue stick join two papers?
A glue stick holds a soft material called an adhesive. Adhesive is a name for something that helps things stick together. When the stick rubs across paper, a thin layer stays behind on the page.
In the diagramA glue layer holds two pieces of paper togetherEnlarged side view · purple stands for the adhesiveGluestickUpper paperLower paperGlue touches both facesThe dried adhesive joins the paper surfaces.
That soft layer spreads into close contact with the paper surface. A second piece of paper can touch the same layer from the other side. Now the glue touches both pieces. The glue sticks to the paper and also holds together within its own layer.
As the layer dries, it forms a joining film between the sheets. The papers stay paper. A little layer of another material is what holds their touching faces together.
About this explanation
Starting knowledge: Recognize paper, a glue stick and two surfaces touching.
Sources
- Henkel — Pritt Stick Technical Data Sheet
- American Chemical Society — Sticking with Chemistry