Corrosion Resistance of Lignin-Based Thermoplastic Adhesive-Bonded Aluminum Joints

Yu, Zeyang [ORNL] (ORCID:0000000209002374); Gao, Yawei [ORNL] (ORCID:0000000225672853); Jun, Jiheon [ORNL] (ORCID:0000000195005637); Lim, Yong Chae [ORNL] (ORCID:0000000321773988); Kanbargi, Nihal [ORNL] (ORCID:0000000278976957); Wade, John [ORNL]; Bowland, Christopher [ORNL] (ORCID:0000000212294312); Naskar, Amit [ORNL] (ORCID:0000000210940325)

doi:10.1021/acsapm.6c02247

DOE OSTI · 3682457

Corrosion Resistance of Lignin-Based Thermoplastic Adhesive-Bonded Aluminum Joints

Yu, Zeyang [ORNL] (ORCID:0000000209002374)·Gao, Yawei [ORNL] (ORCID:0000000225672853)·Jun, Jiheon [ORNL] (ORCID:0000000195005637)·Lim, Yong Chae [ORNL] (ORCID:0000000321773988)·Kanbargi, Nihal [ORNL] (ORCID:0000000278976957)·Wade, John [ORNL]·Bowland, Christopher [ORNL] (ORCID:0000000212294312)·Naskar, Amit [ORNL] (ORCID:0000000210940325)

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Abstract

Adhesive-bonded joints are essential for lightweight, multimaterial automotive structures. We developed a lignin-based thermoplastic adhesive with adhesion strength comparable to conventional epoxy adhesives (20–23 MPa), while offering exceptional durability, recyclability, and corrosion resistance. Unlike commercial epoxy adhesives requiring refrigerated storage, our adhesive retains its bonding potential after a year of ambient conditioning. Bonded joints can be repeatedly disassembled and rejoined with less than 2% strength loss. After 500 h of salt fog exposure, the adhesive-bonded aluminum joints exhibited a 24% strength reduction, compared to 61% reduction in strength of joints based on a commercial epoxy adhesive.

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Yu, Zeyang [ORNL] (ORCID:0000000209002374), Gao, Yawei [ORNL] (ORCID:0000000225672853), Jun, Jiheon [ORNL] (ORCID:0000000195005637), Lim, Yong Chae [ORNL] (ORCID:0000000321773988), Kanbargi, Nihal [ORNL] (ORCID:0000000278976957), Wade, John [ORNL], Bowland, Christopher [ORNL] (ORCID:0000000212294312), Naskar, Amit [ORNL] (ORCID:0000000210940325). 2026-08-01. Corrosion Resistance of Lignin-Based Thermoplastic Adhesive-Bonded Aluminum Joints. https://doi.org/10.1021/acsapm.6c02247

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