NMR imaging of adhesive-bonded structures: the use of the T1 and T2 relaxation time information

—Nuclear magnetic resonance imaging (NMRI) is used to obtain cross-sectional images of three poly(vinyl alcohol) (PVOH) stabilized poly(vinyl acetate) (PVAc) emulsions in glass vials and in glue-lines between a wood block and a ceramic tile. From a series of T, and T2 weighted images acquired with different repetition and echo times, pure T, and T2 images of the emulsions are calculated. The T1 relaxation times are between 0.83 and 1.04 s and the T2 relaxation times between 15 and 26 ms for the emulsions. The relaxation information is used to compute a proton spin density image. Optimum pulse sequence parameters are determined to detect and to create a maximum intensity contrast for the signals of two different emulsions in a 200-300 μm glue-line.