Identifying and Remedying Multiple Trace Contaminants in Manufacturing Environment to Prevent Bond Failure

Control of adhesive bonding operations to guarantee reliable bond performance requires careful, quantitative bond surface control. This includes: i. Knowledge of detrimental contaminants present in the bonding environment, ii. Threshold amounts of these contaminants that cause degradation of bond performance, iii. Reliable methods for detecting these contaminants on the bond surface that can be practically deployed in manufacturing, and iv. Methods for successful remediation of contaminated surfaces. Contaminants to be evaluated include specific tapes and sealants known to leave residues of unknown effect, and representative mixtures of contaminants likely to encountered in a bonding environment. Handheld inspection tools to be used for detection and quantification of contaminants include infrared spectroscopy, X-ray fluorescence, Laser Induced Breakdown Spectroscopy, and contact angle measurements. Phase I work will focus on RT cure paste adhesives, known for sensitivity to contaminated bond surfaces. Effects of contaminants on adhesive bonds will be evaluated using double cantilever beam specimens. Remediation methods will include contaminant removal via solvent cleaning to a quantifiable endpoint followed by abrasion or plasma treatment to complete contaminant removal and create a quantifiable chemically active bond surface.