THE EFFECT OF THE RESIN HARDENER RATIO ON THE COMPRESSIVE BEHAVIOR OFAN EPOXY SYSTEM/

An investigation was carried out on the variation of the mechanical pr operties of an epoxy system formulated with eight resin/hardener ratio s. The ratios used covered a range of epoxy rich and hardener rich, as well as stoichiometric compositions. The tests were performed in comp ression and the results obtained were correlated with the macromolecul ar network developed. The epoxy rich systems showed brittle behavior, which was associated with the development of a rigid macromolecular st ructure. The hardener rich systems showed fracture behavior characteri stic of materials with a large deformation capacity. This behavior was associated with the presence of non-reacted points on the hardener mo lecule and the introduction of a segment with rotational capacity in t he macromolecular network. The degree of cure and the number of functi onal points consumed on the hardener molecule were identified as the t wo parameters that control the compression behavior of the epoxy syste m studied.