PRACTICAL ISSUES AFFECTING SEALANT PERFORMANCE IN AUTOMOTIVE APPLICATIONS

Performance of automotive sealants are affected by the same three factors that control the performance of adhesives, paints, and coatings: Polymer (sealant) composition, surface preparation, and application and curing. When these three factors are controlled, sealant performance is invariant. In reality, sealant performance is not invariant, and a significant proportion of automotive quality issues and recalls are due to the failure of sealants to perform as intended. This presentation discusses automotive sealant performance and presents results of failure analyses from several case studies. In the majority of instances, performance issues are related to either failure to adequately control surface preparation processes or failure to control the effect of environment on sealant cure rates. Straightforward techniques for introducing quantitative control into these processes are presented and discussed.