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 T 2 weighted images acquired with different repetition and echo times, pure T, and T 2 images of the emulsions are calculated. The T 1 relaxation times are between 0.83 and 1.04 s and the T 2 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.