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A series of FT-IR spectrometric studies has been performed to understand the latent track structure in poly(allyl diglycol carbonate), PADC, which were exposed to proton beams with energies of 20, 30 and 70 MeV. These energies are too high to register etchable tracks in PADC. Chemical damage parameters, such as damage density, effective track core radius and radiation chemical yields, for losses of ether bond, carbonate ester bond and CH groups in PADC are evaluated as a function of the stopping power, which were compared to the previous results for 5.7 MeV proton and heavy ions, between He and Xe.Graphs of the chemical damage parameters are given at the wide stopping powers ranging from 1 to 12,000 keV/µm. The decreasing behaviors of the ether and carbonate ester bonds are on the almost identical trends with those of the heavy ions. On the contrary to this, the reducing behavior of CH groups is similar to that of the gamma rays. Different dependence of the chemical damage parameters for the loss of CH groups is found on the stopping powers between the both sides of the detection threshold as an etched track detector.

FT-IR spectral studies have been made for CR-39 detectors irradiated by gamma-rays, protons and carbon ions. An absorption peak for CO 2 appeared and grew with the fluence. The peak height was found to decrease gradually by storing in air. Absorbance of the OH group produced by ion bombardment was observed separately from that of adsorbed water using a FT-IR system on the beam line. The concentration of OH group would govern the rate of penetration of chemical agents along the track.

Radiation chemical yield, G value, for loss of carbonate ester bonds in PADC films, exposed to gamma ray from intense Co-60 source, has been determined by means of FT-IR spectrometry. The obtained value of 20 (scissions/100 eV) is fairly higher than that from heavy ion irradiations. It was found the density of hydroxide group in the film significantly increased by the exposure in air but hardly changed in vacuum.

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