Title: Plasma Treatment Efficacy on Unclean Surfaces for Bonding Processes

Authors: Rose Roberts, Joe Fehrman, Gabby Brown, Matthew Nichols, Ian Smith, Bill Buschle, Giles Dillingham

DOI: 10.33599/nasampe/c.22.0120

Abstract: Plasma treatment is known for its ability to activate a surface for improvement of bond strength. When an oxygen-containing gas is used, highly active oxygen radicals and ozone molecules chemically bond oxygen to the surface functional groups, creating a more polar and reactive surface that will more readily react chemically with an adhesive. Oxygen radicals and ozone may also oxidize certain molecules completely to CO2 and H2O thereby removing them from the surface, creating a molecularly clean surface which may be ideal for bonding purposes. In this work, we examine several material surfaces used in industrial processes, including polycarbonate, carbon fiber reinforced polymer, and cast aluminum. Each material was either unintentionally contaminated in a production facility or intentionally contaminated in the lab with a residue found in the production line to simulate a contamination event. Plasma treatment was used to clean and treat the surfaces with and without the presence of contaminant. The effect of plasma was characterized using FTIR spectroscopy and water contact angle. This work showed that in certain cases, plasma treatment was unable to remove all of the surface contamination within practical treatment times, preventing full activation of the substrate surface. It was found that characterization of the contaminant level of the surface prior to plasma treatment is an important step that provides more confidence in the ability of a plasma process to activate the underlying substrate to ensure the expected adhesive bond strength can be achieved.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000120

Pages: 11

Price: $22.00