Radical Polymerization of Trifluoromethyl- Substituted Methyl Methacrylates and Their Application for Use in Pressure- Sensitive Paint

Three CF3-substituted methyl methacrylates (MMAs), 2,2,2-trifluoroethyl methacrylate (TFEMA), 1,1,1,3,3,3-hexafluoroisopropyl methacrylate (HFIPMA) and nonafluoro-tert-butyl methacrylate (NFTBMA), were polymerized by conventional radical polymerization to give oxygen-permeable polymers for application in pressure-sensitive paint (PSP). The radical copolymerizations of styrene with TFEMA, HFIPMA, or NFTBMA were carried out to examine the effect of CF3 groups on the polymerizability. The e values increased in the order of MMA (0.40) < TFEMA (0.76) < HFIPMA (1.19) < NFTBMA (1.31). The homopolymers of TFEMA, HFIPMA and NFTBMA (PTFEMA, PHFIPMA, and PNFTBM, respectively) were examined as polymers for use in PSP using 5,10,15,20-tetrakis(pentafluorophenyl)porphinato platinum(II) (PtTFPP). The PSP consisting of PNFTBMA and PtTFPP exerted very high pressure sensitivity and very low temperature sensitivity. In the absence of oxygen, the temperature sensitivity decreased in the order of PTFEMA > PHFIPMA > PNFTBMA = PMMA, which corresponds to the order of glass transition temperatures (T-g). However, the activation energies of the overall process of the luminescence quenching by oxygen were found to be 16.8 (PMMA), 13.0 (PTFEMA), 6.8 (PHFIPMA), and 4.3 kJ mol(-1) (PNFTBMA). Therefore, the low temperature sensitivity of PNFTBMA was attributed to its high degree of substitution with CF3 groups and to its relatively high T-g value. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 963-972