system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a metric for adhesive strength?

And what is the level of difference between a band aid and duct tape?
gpt
Yes. This is generally correct. N/m^2 or lb/in^2 (psi) and other derivatives. 

It can be hard to find. As it’s a) not quite that simple- the backing provides a certain strength so adhesive is strength usually measures just pulling directly away from the plane of the backing. And b) temperature dependence. (See below)

I rarely see this value for tapes you get in the store. It’s frequently given for industrial grade tapes. 3M website is a good place to look because many products do have it. And they make a lot of tape. But not all of them have the value. 

It’s also complicated by the fact that adhesive strength for most tapes varies with temperature. When quite cold the adhesive is hard and not sticky. When warm it’s very sticky and can get runny. So they usually give 2 or 3 values (for industrial tapes) @ 0C 30C 60C

Also relevant for your bandaids example. You’d want good adhesive properties around 60C, but you need it to be less than the sheer strength of skin- which can be quite low in the elderly or edematous.  It’s a tough trade off. Because that regular bandaid you stick on your finger has no chance of staying, but those athletic ones will stick until you rip it off- generally leaving adhesive behind.