Which is Stronger Glue or Tape? - Constantly Curious (1)

wildthoughts (26)in #science • 7 years ago

The oldest glue in the world is over 8 thousand years old, and comes from a cave near the dead sea.
Ancient people used this glue made from a mixture of animal bone and plant materials to waterproof baskets and construct untensils.

And for thousands of years later, plants and animals were the glue that held human civilization together.

Today, we have enough types of tape and glue to build and repair almost everything.
But what gives glue and tape their stikiness? and in one stronger than the other?

Adhesives can be made from synthetic molecules or natural proteins and carbohydrates like the vegetable starch dextrin, the milk protein casein, and the terpenes in tree resin. In order to work, glue and tape need both adhesive bonds and cohesive bonds.

Adhesive bonds occur between an adhesive’s molecules and the molecules of whatever it’s sticking to.

Cohesive bonds happen between glue and tape’s own molecules, holding it together. Most glue consists of adhesive polymers dissolved in a solvent that prevent them from sticking to the inside of the bottle.

The strong smell of many glues come from the solvent, which evaporate when expose to air. Some glues uses water as a solvent, but others used chemicals that can be harmful to inhale.

Glues with two or more components that chemically react instead of just drying can create stronger bonds. Both the adhesive and cohesive bonds of glue are strong, but the drying process makes them irreversible. This is why, if a glues surface is broken after it dries, it can’t be reattached without new glue.

By contrast, when tape is applied to a surface, it forms weaker, reversible bonds, so you can peel a piece of tape off a surface and use it again. This weak bonds, called Van der Waals forces, can occur between any two materials, but if they’re extremely close together, closer than the naked eye can see.