Polymer, Vol.38, No.17, 4413-4415, 1997
Adhesion Behavior of Polyamic Acid Cured Epoxy
The adhesion behaviour or lack thereof, of polyimides is well known. The inherent brittleness of epoxy resins has also led to a search for additives to improve the physical properties of epoxy. In order to improve both of these properties, we utilized a unique strategy to cue a diepoxy (diglycidyl ether of bisphenol A) with a polyamic acid derived from oxydianiline and pyromellitic dianhydride. The polyamic acid synthesis was conducted in a low boiling point solvent consisting of tetrahydrofuran and methanol (80/20) and nor traditional high boiling point aprotic solvents such as dimethylacetamide. This resulted in a material that had adhesion superior to both the pure epoxy and the pure polyimide. The state of cure was also seen to have an effect of the adhesion strengths.
Keywords:POLYIMIDE