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The objective of this work is to demonstrate the feasibility of pressure measurement instrumentation using anodized-aluminium pressure-sensitive paint (or AA-PSP) for application in unsteady flows. An anodized procedure was applied to an aluminium tape that can be easily placed on a model even when it is mounted in a wind tunnel. The response time of the PSP coating is assessed using a calibration rig that generates fast pressure steps or sinusoidal pressure fluctuations up to 1 kHz. A pointwise measurement system made with a Cassegrain telescope and a photomultiplier tube was designed to collect the PSP luminescence. The spot displacement on the model surface was carried out by using a 3D moving bench. A camera is used to identify the spot position according to the model geometry. An application in a wind tunnel was performed on a forced shock wave oscillation test, generating amplitude variations up to 25 kPa. The calibration problem due to non-uniformity of the anodized properties did not allow quantitative data processing of pressure levels. Nevertheless frequency analysis demonstrates that the coating is able to follow the pressure fluctuations, as shown by comparison with standard pressure transducers.

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The reactivity of model compounds representative of the structures resulting from the first steps of curing in uncatalyzed (or LiClO4‐catalyzed) N,N‐diglycidylaniline/aromatic amine systems was studied. The results indicate that the intermolecular etherification either does not occur or is very slow under these conditions. Moreover, the latter situation is observed only in the very specific configuration when two hydroxyl groups are very close to each other. From these experiments, it can be inferred that the most likely reactions occurring after the epoxy‐primary amine addition in uncatalyzed N,N‐diglycidylaniline/aromatic amine systems are the are the epoxy‐secondary‐amine addition and the cyclization reactions discussed in a previous paper.

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