Effect of gamma radiation on fluoropolymers |
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| Authors: | A Contreras‐Garcia E Bucio F León‐c C J Booth P E Cassidy |
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| Institution: | 1. Departamento de Química de Radiaciones y Radioquímica, Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México DF 04510;2. Facultad de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México DF 04510;3. Department of Chemical and Biochemistry, Texas State University, 601 University Drive, San Marcos, Texas 78666 |
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| Abstract: | A series of fluoropolymer films were synthesized by reacting several bisphenol monomers with 1,3‐bis(1,1,1,3,3,3‐hexafluoro‐2‐pentafluorophenyl methoxy‐2‐propyl)benzene via a nucleophilic aromatic substitution to form polyethers. The bisphenols used included two diphenol‐substituted spirodilactams (SDL; aliphatic and aromatic), biphenol, bisphenol A, bisphenol AF, bisphenol O, and bisphenol F to form seven different polymers. Polymers were irradiated by a Gamma beam 651‐PT at a dose rate of 10.5 kGy/h; the absorbed dose in each film was varied between 300 and 1000 kGy. The effect on the chemical structure upon radiation was studied by DSC, TGA, FTIR‐ATR, and NMR after and before irradiation. Thermal analysis showed a lessened thermal stability and a lower Tg after irradiation. Further, irradiation caused a decrease in molecular weight as a result of cleavage of sp3 bonds. These data allowed calculation of the radiochemical yield scission (Gs) for each of these polymers. The SDL aromatic system proved the most radiation‐resistant. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1617–1626, 2009 |
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| Keywords: | degradation fluoropolymers G‐values polyethers γ ‐radiation |
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