a slight rougness can procure a mechanical ancorrage (5

http://www.xpolymers.it/adesione_al_metallo.html you can try this

Basically you need to upgrade the bond order from intermolecolar to intramolecular. Since chemical structure of the polymer is rigid, my advice to change surface chemistry of your substrate

Hello

As I know,the best solution for your work is the usage of tie layers.

tie layers are containing polymers which are grafting with polar groups like maleic anhydride, silanes and others.

Regards

Maziar

We need to know the metal and the polymer(s) to be able to give any worthwhile answer.