The relation between the adhesive application method and the fatigue lifetime for a photocatalytic adhesive joint

Joint design, surface preparation and adhesive selection are considered the most important factors that control fatigue life of adhesive joints. Early research by the authors showed that for adhesive glass-polycarbonate joints using the photobond 4455 adhesive the statistical spread in fatigue life was large. Follow up research showed that the adhesive application method was the main causal factor in determining the fatigue life. Some application methods yielded good shear strength but low fatigue life. The results suggest that polarity of the photobond 4455-monomer results in micro defects being introduced by certain application procedures. This can lead to differences in fatigue life of a factor 10 or more.