Title: Tailoring Epoxy Foam Properties with an Innovative Process Approach Using Co2 as Blowing Agent
Authors: Simon T. Kaysser, Christian A. Keun, Christian Bethke and Volker Altstädt
Abstract: For modern applications in aviation and electric mobility, foamed polymers are in strong demand due to their low density, tailorable mechanical properties and thermal insulation. The properties of polymer foams are derived from their morphology and matrix. More demanding applications in aviation, for example sandwich structures with SMC outer layers and foamed epoxy core, request specific foam systems to meet flame retardance regulations as well as thermo-mechanical process requirements. However, the production of epoxy foam systems, especially without using hazardous chemical blowing agents, for high temperature applications is a challenge still to be resolved. CompriseTec GmbH and the Department of Polymer Engineering (University of Bayreuth) are developing tailored epoxy foam systems using an innovative approach. Therefore, CO2 blocked amine hardeners in the form of carbamates combined with adaptable pre-curing systems and additives are used to tailor foam properties. A tailorable morphology, high mechanical and temperature properties (Tg = 150 – 200 °C) can be achieved in combination with further features, such as flame retardance. In the EUROSTARS funded project “DiaPore”, epoxy carbamate foam systems were developed showing the potential of tailoring specific properties, focusing on low to high density and medium to ultra-fine closed cell morphology. First flame-retardant modified systems were successfully evaluated.
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Conference: SAMPE 2020 | Virtual Series
Publication Date: 2020/06/01
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