Title: More Sustainable Alternatives to 4,4’-DDS/DDM for Epoxy Systems for the Manufacturing of Composites

Authors: Michael DiGiacomo, Dr. Stefan Ellinger, Peter Frost, Dr. Gaetano La Delfa, Maria Luisa Longo

DOI: 10.33599/nasampe/c.24.0369

Abstract: Lightweight and high-strength materials have consistently played a key role in the construction of fuel-efficient and high-performing aircraft. In order to reduce aviation contribution to climate change, we looked into sustainable and low toxic alternatives to 4,4’-DDS and DDM/MDA, the most commonly used epoxy curing agents used to manufacture high performance composite materials. With the pressure to replace and improve these curing agents with sustainable materials, Arxada AG has evaluated different aromatic amine mixtures with low toxicity profiles, to be incorporated into standard Bisphenol A and Multifunctional epoxy resins systems. Those aromatic amine combinations bring promising mechanical results and high thermal resistance, which are comparable and can be used as 4,4’-DDS and DDM/MDA replacements, to manufacture various lightweight and high-strength composite parts. The identified mixtures, having a lower melting point than 4,4’-DDS and DDM/MDA, prove to be beneficial in reducing processing temperature and allow their use in various composite processes, such as prepregs and liquid composite manufacturing. In addition, those mixtures of aromatic amines provide a remarkable improvement in water uptake, opening new opportunities for the adoption of composite parts in new applications with high moisture exposure. The achieved results in both Bisphenol A and Multifunctional epoxy resins systems allow the replacement of 4,4’-DDS and DDM/MDA both in aerospace and non-aerospace applications.

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Conference: CAMX 2024 | San Diego CA

Publication Date: 2024/9/9

SKU: TP24-0000000369

Pages: 17

Price: $34.00