In this study, fast-response polymer-ceramic pressure-sensitive paints (PC-PSP) were developed and evaluated for pressure measurement under low-pressure conditions. The PC-PSP using poly[1-trimethylsilyl)-1-propyne] (poly(TMSP)), which has high oxygen permeability under low-pressure conditions, was developed in this study. The static and dynamic characteristics of the developed poly(TMSP)-based PC-PSP were evaluated in comparison with those of conventional poly(isobutyl methacrylate) (poly(IBM)) binder and ruthenium-complex-based PC-PSPs, which have been used for pressure measurements under atmospheric pressure conditions. The particle mass content of titanium dioxide of PC-PSPs with poly(TMSP) was changed from 90 wt% to 98 wt% to increase the frequency response. The critical pigment volume concentration, so called CPVC, of the PC-PSP with poly(TMSP) and hydrophobic particles and hydrophilic particles were 95–98 wt% and 90–95 wt%, respectively. The PC-PSP using hydrophilic particles with poly(TMSP) and a particle mass content of 98 wt% could provide a cut-off frequency of approximately 4.5 kHz and a high local Stern–Volmer coefficient of 0.5 at low pressure of 2 kPa.

Antioxidants were applied to a dual-luminophore pressure-sensitive paint (PSP), and the effects on photodegradation caused by exposure to excitation light were studied. Three types of antioxidants that are commonly used for the photostability enhancement of polymers were added to a dual-luminophore PSP, and degradation rates and pressure/temperature sensitivities were investigated by coupon-based tests. One-hour-long aging tests were performed in a pressure chamber with a continuous excitation light source under dry air and argon atmospheres at 100 kPa and 20 °C. As a result of the aging tests, a singlet oxygen quencher type antioxidant was found to reduce the degradation rate by 91% when compared with the dual-luminophore PSP without antioxidants. This implies that singlet oxygen has a dominant role in the photodegradation mechanism of the dual-luminophore PSP.

In this paper, we propose a photodegradation correction method for the dual-luminophore pressure-sensitive paint (PSP) measurement using lifetime-based imaging, which was proposed for correction of the temperature-induced error but has suffered from photodegradation in the previous studies. We introduced a parameter that characterizes the photodegradation of a dual-luminophore PSP as the intensity ratio between the two luminophores. The changes in the calibration coefficients for the pressure and the temperature due to photodegradation were corrected based on this parameter. In this study, a coupon-based calibration test was performed, and the luminescence characteristics of the dual-luminophore PSP including photodegradation were investigated. Then, the proposed method was applied to a coupon-based validation test and a jet impingement test, and the effectiveness of the method was evaluated by comparing results with and without correction. The pressure measurement accuracy was significantly improved by photodegradation correction.