FTIR Spectral Evaluation of Polyurethane Adhesive Bonds in Perspex Canopies of Aircraft

Failure of capron glue (polyurethane) adhesive joint between nylon strips and perspex canopy of aircraft has been studied by Fourier transform infrared spectral analysis. It is concluded that the brittle failure of the joint is due to time-dependent crosslinking of residual isocyanate group with residual hydroxyl or the amino groups produced as a results of reaction of absorbed moisture with the isocyanate moiety: A service life of eight years has been estimated for the glue joint