Sorry, 'strong power glue' doesn't tell us enough, -Name your glue -
Isopropyl will remove only elmers glue from plastic, not super glue. once it gets on there, you can't remove it.
Anything that could remove it could also damage the plastic.
There is almost no way to do this without destroying the plastic. As you didn't say WHAT KIND of plastic, it's hard to be more help.
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Depends on the type of plastic. Many plastics have glue made from their solutions. Some can be partially dissolved and joined together by the right chemical, some needs to be prepped with an etching agent to get a glue to stick to them.
I would cut it off with a very sharp craft knife.
Paul E. Cope invented Thermo plastic glue also known as "Hot Glue" it is used in Hot Glue guns.
try super glue or go to a auto wrecker
A good glue you can use for soft plastic which is a flexible material is Gorilla Glue.
plastic (polymer)
You might try a hair dryer , sometimes being warmed up will release the glue better.
No plastic is used as glue, though some components may be the same in each other.