Everyday Science 1 | Page 18

Glue is a form of adhesives. All adhesives have the same function of holding things together. But you may have wondered what causes glue to be so sticky? The stickiness of adhesives is attributed to molecular bonds in the formation of these materials. It’s known that every substance has a set of positive and negative charges. In order to form a bond between two substances, their opposing charges need to be attracted to each other. For instance, to for hydrogen chloride (HCL), a positive hydrogen charge needs to be attracted to a negative chlorine atom and neutralize to create a strong neutral bond. Adhesives have long chains of protein molecules that create bond with any surface they are spread over by getting attached to the pores and holes of the material. Consequently, smooth materials such as glass and metals don’t interplay with adhesives for their lack of pores.

Glue, in specific, consists of a liquid like water combined with an adhesive material. When it is applied on a surface, the same mechanism is applied. After that, when the liquid evaporates, and the glue dries, it hardens and makes the molecules stick together.

How Glue Glues?

Written by: MAHMOUD ELSHAZLY