Characterization of pressure-sensitive paint based on mesoporous silica particles under near-vacuum conditions

The static characteristics of three mesoporous silica particle (MP) pressure-sensitive paints (PSPs), containing polystyrene (PS), room temperature vulcanized silicone rubber (RTV), and poly[1-(trimethylsilyl)-1-propyne] (PTMSP) as polymers, were calibrated and compared to those of polymer/ceramic (PC)-PSP under near-vacuum conditions. According to the results, PTMSP/MP-PSP exhibited the highest pressure sensitivity and lowest temperature dependency, which make it suitable for determining tiny pressure variations. RTV/MP-PSP, which presented a relatively high pressure sensitivity and good photostability has also a good potential for application under near-vacuum conditions. By comparing PTMSP-PSPs with and without mesoporous silica particles, it was found that the addition of particles improved the pressure sensitivity and photostability, but did not increase the temperature dependency significantly. To correct the degradation of PSP pressure sensitivity under near-vacuum conditions, a method for eliminating the test errors caused by irradiation under near-vacuum conditions was proposed.