ION-BEAM-INDUCED CONVERSION OF PVC INTO A CONDUCTING POLYENE

The irradiation of PVC films with a beam of 1 MeV alpha particles indu ces the dehydrochlorination of the polymer molecule leading to the for mation of sequences of conjugated double bonds. Mass spectrometry of t he fragments desorbed during irradiation shows two main peaks that res ult from H-2 and HCl release. The kinetics of the HCl peak is in accor dance with a model of H and Cl atoms liberation to form the HCl molecu le in the bulk according to the usual radiolysis scheme. The optical a bsorption spectrum shows the formation of conjugated segments involvin g 8 double bonds for a fluence of 10(15) He+/cm(2), whereas the dehydr ochlorination rate has reached a low stable value, Implications for th e production of new electronic properties are adressed.