Pressure-sensitivity stability of poly[1-(trimethylsilyl)-1-propyne]-based pressure-sensitive paint for low-pressure conditions

Pressure-sensitive paints using poly[1-(trimethylsilyl)-1-propyne] (PTMSP) as a binder polymer are capable of capturing subtle pressure fluctuations under low-pressure conditions, but the pressure sensitivity is unstable. The dependence of the pressure sensitivity stability on environmental factors and coating parameters was evaluated under low-pressure conditions. The pressure sensitivity decreased from 56.3 to 42.5%/kPa at an extremely low pressure after 60 min, and the stability decreased significantly as the background pressure was reduced. An apparent change in the pressure sensitivities and stability was observed from 278 to 318 K, with optimal performance being obtained at 298 K. A comparison of the pressure sensitivities and emission intensities of shaded and irradiated samples stored at low pressures indicated that the excitation light hardly aged the binders. The pressure sensitivity stability decreased as the luminophore concentration increased, while an increased in the paint thickness improved both the pressure sensitivity and stability.