Enthalpy relaxation phenomena of epoxy adhesive in operational configuration: Thermal, mechanical and dielectric analyses

摘要

Thermal cycling in space environment can cause physical aging of polymers used in structural adhesive bondedudjoint. Later, they can initiate failure. A methodology to follow physical aging effects on their thermal, mechanicaludand dielectric properties is applied to a commercial epoxy adhesive. The analytic description, using Tool,udNarayanaswamy and Moynihan model gives a good description of the enthalpy relaxation. It is completed by audphenomenological analysis of the evolution of the adhesive thermal transitions, mechanical properties and mo-udlecularmobility. Testedsamples with bondedassembly are representative ofin serviceconudfiudgurations. The inudfludu-udence of physical aging on the adhesive and the associated bonded assemblies is analyzed.