Ashit Mehta

Adhesion (fracture energy) of electropolymerized poly(n-octyl maleimide-co-styrene) coatings on copper substrates using a constrained blister test

The fracture energy required to separate electropolymerized n-octyl maleimide/styrene polymer film from various copper substrates was measured using a constrained blister test. A G value (strain energy release rate) of 75 J/m2 at 0.5 mm/min debonding rate was found for separation of the n-octyl maleimide/styrene polymer film from a smooth copper surface. This value is slightly higher than the G value (60 J/m2) of pressure-sensitive adhesive tape on copper, and much higher than the estimated 4.4 J/m2 of Kapton® polyimide on a similar copper surface. It was found that rough surfaces having a regular pattern substantially increased the adhesion strength of the polymer coatings. The polymer films adhered well to the rough surfaces; attempts to separate the polymer film from the copper surface resulted in cohesive failure.