Based on luminescence quenching of chromophoric probes in oxygen permeable polymer matrix

pressure sensitive paint (PSP) and its devices have been developed as a kind of functional materials in recent years.The pressure sensitivity of PSP not only depends on the probe molecules

but also on the polymer matrix.In this work

tetrakis(pentafluorophenyl)porphyrin platinum (PtTFPP)

as a luminescent probe

was composed with polydimethylsiloxane (PDMS)

polymethylphenylsiloxane (PMPS)

polymethyltrifluoropropylsiloxane (PFS) and trifluorochloroethylene-vinyl acetate copolymer (PFC) respectively

and then their luminescence quenching behaviors were measured at an excitation of =365 nm with various oxygen concentrations from 0% to 100%.The ratio I0/I100 is used as oxygen sensitivity of PSP films

where I0 and I100 represent the fluorescence intensities from films exposed to 100% nitrogen and 100% oxygen

respectively.The I0/I100 values of the PtTFPP-based films are evaluated.It is found that the plots of I0/I versus [O2] with identical Ksv are obtained and a two-site model fits the experiment data very well for the PtTFPP/polymer systems

except PtTFPP/PFC films.The values of I0/I100 and Ksv for such materials increased with increasing the oxygen permeability of the polymer matrix

i.e.PDMS PMPS PFS PFC

which is identical with theoretical reasoning.Therefore it could be concluded that the oxygen quenching for the PSP materials in this work showed a diffusion-controlled mechanism.