| The radiation effects of F23 polymers have been studied from the need of background. Polymers including fluororubber F2311 and fluororesins F2313, F2314 were irradiated by gamma-rays in all three ambiences vacuunu air and nitrogen, the gaseous products generated after radiation at different doses or dose rate have been analyzed, the degradation or crosslinking of radiation, the changes of mechanics and dynamic mechanics have been measured. The mechanisms of radiation degradation for these polymers have been discussed also. The conclusions have been stated bellow:The main gaseous products formed by radiated F231K F2313 and F2314 have been identified and quantified with gas chromatograph-mass spectrometer (GC-MS) ion specific electrode(ISE) and atomic absorption spectrometry (AAS), the amount of H2 CO2 HF and HC1 all increase with the dose. For the rubber state, with good diffusion, F2311 is seriously influenced by dose rate, less gas is emitted from it after radiation at same dose and a high dose rate. And because of part crystallization, the amount of gas products for F2313 and F2314 are controlled by diffusion, they are not obvious influenced by the reaction time and dose rate.According to the content of H2 CO2 HF and HC1 produced by these three fluoropolymers in variety ambiences, the yields of them have been calculated. The weight losses of F2311, F2313 and F2314 in three ambiences are all increase with dose, the order is: in air> in vacuum> in nitrogen. It is indicated that the total weight loss declines with the addition of dose rate.The changes of characteristic peaks for these three fluoropolymers after radiation have been detected with infrared spectroscopy. It is found that the height of main groups such as C-F C-C1 and C-H etc in the polymers is changed. The groups -CF=CH- and -CF=CF- are emerged in F2311 after radiation at the dose of 50kGy, and =C=0 is formed in air ambience. The -CF=CF- in F2313 is found after radiation at a dose of 5kGy, there is no -CF=CF- in F2314 until the dose up to 250-500kGy, but a strong peak of =C=O in F2314 is examined in air ambience.With pyrolysis gas chromatograph-mass spectrometer (GC-MS), the crackates such as vinylidene fluoride trifluoroethylene and tetrofluoroethylene etc are detected for F231K F2313 and F2314 after radiation in all three ambience and various dose,the different content of these crackates are compared.The stretch cross sections of three fluoropolymers after radiation are observed with scanning electron microscope (SEM). The mal-distributed coarse lamellar tearings are discovered, and crimps are found in them at the high dose, these inferred a more severe destroy.For F2311, the changes of elements on its surface and the shift of Cls after radiation have been investigated by X rays photoelectron spectrometry (XPS). The combination energy of F-C-F and Cl-C-F move to low side due to the part loss of F or Cl in radiolysis.The molecular weights of three fluoropolymers before and after radiation have been measured with gel permeation chromatograph. The molecular weights of them decrease rapidly with the increment of dose. The fitted curves between molecular weights and doses reveal the variation regulation of number-average molecular weight > weight-average molecular weight or viscosity-average molecular weight in different ambiences. The velocity constants of radiation degradation for F2311 > F2313 and F2314 in three ambiences are calculated according to the mechanism of random breaking. The order of these constants is F231K F2313< F2314.The formation of gel in three fluoropolymers after radiation indicates that degradation and crosslinking have taken place at the same time during radiation. The content of gels gradually increase with the dose at early stage, the maximum is at the dose of SOkGy, then they decrease with the addition of dose. But at a same dose, when the dose rate is high the content of gels is low. The order of content of gels is F2311> F2313> F2314. The parameter calculated with p(/q0 of F2311 is greater than 1, bu...
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