Proton beam induced degradation of Pioloform® (polyvinyl butyral (PVB)) support films used for analysis of biomedical tissue sections

Pioloform®, an often used support film for ion microprobe research is a terpolymer of polyvinyl butyral (PVB) and ≲ 18 mass % polyvinyl alcohol (PVA). Simultaneous off-axis Scanning Transmission Ion Microscopy (OA-STIM) and Elastic Backscattering Spectrometry (EBS) measurements have been used to measure the evolution of the C, H and O contents for an increasing proton fluence. The results showed that the composition at zero proton-fluence was in close agreement with the theoretical atomic composition. This strongly suggests OA-STIM measurements. With increasing proton fluences preferential loss of H and O was observed from the films.