Educate & Applicate: 3 Reasons Adhesives Fail
Claudia Ramirez· December 23, 2020
Ever tried hanging a light shelf on the wall?
Measured it, leveled it, stuck it up with a tape, and then ever so carefully placed on it your tiny little trinkets that had needed a home. You then walked away satisfied that it was all in place for good.
Hours went by, maybe even days or weeks. Then one night, in the quiet of the dark… you’re sleeping away. Dreaming about long summer days and hot sunny beaches.
Suddenly… a loud THUD! Followed by a horrendous clatter.
Startled awake, you jump out of bed, rushing to see what all the commotion is. You feel it before you see it… the fragments of those tiny trinkets under your feet.
“What in the world happened?” you ask yourself.
And the answer is really quite simple. You experienced adhesive failure. The tape you thought was stuck for good simply wasn’t.
You’re probably wondering how that could possibly happen. Tape is tape after all, isn’t it? Why does it sometimes fail to do the job it’s made for?
We asked our experts in research and development to help us explain how adhesives fail. Three classical types of failure are the most common:
1. Adhesion Failure
Adhesive failure happens when the tape takes on a mind of its own, and the bond in the tape gets separated from the surface of the material you’re trying to attach it to. What essentially happens is the tape sticks stronger to its internal cohesive forces than to the surface it should be adhering to.
And in the middle of the night, you get awakened with a THUD! That adhesive just wasn’t interested in sticking to the wall. End of story.
2. Cohesion Failure
Now, what happens in the opposite situation… if the tape has a more favorable bond to the surface of whatever it's trying to adhere to, but its internal forces are weaker than that bond?
Well, you'll get what's called cohesive failure. The internal bonds that keep the tape together are actually tearing apart. So there’s some stickiness to the surface but not enough to hold, and what you’re left with is a whole lot of residue on the back of the tape, the carrier, and the surface that you’re trying to adhere to… but not a lot of cohesion!
3. Vacuum Failure
Failure of adhesives is not something you want to experience. Whether you’re hanging a light shelf for your trinkets or using adhesives in industrial manufacturing processes where the stakes are bigger. You don’t want adhesion failure. Cohesion failure. And especially not this third kind of failure…
We call it vacuum failure, and it’s something we never want to see because it's more of a quality or processing issue on the tape manufacturer’s side. And that’s last thing any of us want for our products.
What happens with vacuum failure is that you have an adhesive material that acts as an anchor, but that material isn’t good enough to the carrier it's originally applied to. So the adhesive completely bonds to what you’re sticking it to on the surface, but the backing carrier fails. It hasn’t been treated well enough that the adhesive will stay bonded during an application process.
And that wraps up this lesson on the types of failure adhesives sometimes undergo!
Want to learn more about adhesives? Visit our general application solution page!