Title: BR® 179 Non-Chromate Bonding Primer for Aerospace Structural Bonding Applications

Authors: Yiqiang Zhao

DOI: 10.33599/nasampe/s.21.0473

Abstract: For aerospace metal bonding applications, bonding primers are vital for enabling reliable bonding and long term corrosion protection. In order to meet the imperative market need for chromate replacement technology, technical challenges still remain for non-chromate bonding primers such as long term corrosion resistance comparable to chromated primers and improved properties at no cost to overall performance. A novel 121 °C (250 °F) curing non-chromate epoxy-based bonding primer BR® 179 has been developed by Solvay to meet these challenges and provide a path towards sustainability. Using breakthrough technology in non-chromate corrosion protection and toughening, the one-part solvent-based BR® 179 is able to provide 3000 hours long term scribe corrosion resistance of chromated-based systems, while maintaining the required level of mechanical performance. The unique resin chemistry and toughening mechanism of BR® 179 deliver improvement in low temperature (-55 °C or -67 °F) peel properties at high primer thickness (10 μm or 0.4 mil), and improved stability contributing to long shop/shelf life. This paper provides a performance data summary of BR® 179 including handling/spraying, corrosion resistance, mechanical bonding results and shop/shelf life. The compatibility of BR® 179 with various metal surface preparation methods and various epoxy-based structural adhesive systems is also highlighted.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000473

Pages: 16

Price: FREE