Effects of solvents for luminophore on dynamic and static characteristics of sprayable polymer/ceramic pressure-sensitive paint

Polymer/ceramic pressure sensitive paint (PC-PSP) is an optical fast-responding pressure sensor. PC-PSP consists of a polymer and particles as the material for a porous binder layer, and a pressure-sensitive luminophore. The solution of the polymer and particles, and then the solution of the luminophore are separately applied to a model surface. The response time of PSP is mainly determined by the thickness and oxygen diffusivity of the binder layer. However, we found that PC-PSP showed the significantly different response time depending on the solvents for the luminophore despite the same total thickness of the binder layer. Therefore, we investigated the effect of solvents in dissolving luminophore on the PC-PSP characteristics including response time, pressure sensitivity, and luminescence lifetime. PC-PSP's prepared with solvents for luminophore that poorly dissolve the polymer in the binder layer achieved a faster response time of those prepared with solvents that can dissolve the polymer. Furthermore, it was also found that the solvents caused the change in the response time, luminescence intensity and luminescence lifetime of PC-PSP. We have concluded that the different solubility of the solvents may provide the different state of porous structure and the local distribution of luminophore in the binder layer, and it causes the variation of the dynamic and static characteristics of PC-PSP.