Dynamic and mechanical properties of DGEBA/poly(propylene oxide) amine based epoxy resins as a function of stoichiometry

✍ Scribed by F. Fernandez-Nograro; A Valea; R. Llano-Ponte; I. Mondragon

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 914 KB
• Volume: 32
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(95)00122-0

✦ Synopsis

An investigation was carried out into the effect of stoichiometry on the dynamic and mechanical properties of epoxy resins cured with two different poly(propylene oxide) based amine-s. Glass transition temperatures as well as crosslink densities of the networks have been related to the stoichiometry of both mixtures as well as to the structure of the curing agent employed. Mechanical properties have been analyzed as a function of stoichiometry and chain structure of the components used. With the exception of mixtures with an amine/epoxy ratio of 0.6, the stiffness was a minimum around the stoichiometric composition for both systems. A good correlation between the toughness of these materials and their strength and ductility has been found. Toughness behaviour is explained as a function of the network homogeneity and the extensibility of the segments constituting the crosslinked structure.