[tsvika69]

is there a general rule that says which organic functional group gives certain mechnical /chemical properties

for example " if you want better adhesion you should esterify a molecule"

or ethoxylation improves stability of chemicals in certain pH etc.






 

[Enthalpy]

Insofar chemistry obeys simple rules maybe...? 





Adhesion for instance depends on the base material. Silicone glues or potting agents are bad on everything but ceramics, so it's a matter of pairing, not of a single figure like surface tension.

Look at polymer ultrastrong fibres: few years ago, everyone would have answered "it needs functional groups to transfer the force between the long molecules" but meanwhile we have polyethylene fibres.

At chemical resistance your chances may be better.