Effect of γ Ray or Electron Beam Radiation in Air on Radiation Curing of Polycarbosilane Fibers

Polycarbosilane fibers were irradiated by γ ray or 10 MeV electron beam in air. Gel content, chemical structure, molecular weight distribution and pyrolysis properties were studied. The curing dose of polycarbosilane fibers irradiated by γ ray or electron beam is 3 MGy and 6.5 MGy, respectively. Bridge structures of Si—O—Si and Si—C—Si are formed in the irradiated products. Radiation curing mechanism of polycarbosilane fibers are uniform under two kinds of irradiation fields. The effect of radiation curing irradiated by γ ray is better than that of electron beam irradiation at the same absorbed dose, and the ceramic yields irradiated by γ ray are also higher.