SURFACE MODIFICATION OF POLYMERIC MATERIALS BY PULSED ION-BEAM IRRADIATION

Polymethylmethacrylate and polyimide samples were irradiated with 500 keV carbon and hydrogen ions generated by a high intensity pulsed powe r ion beam source. Ion penetration was limited to a few microns at an energy deposition in the range of 0.1-5 J cm(-2) and a dose rate of ap prox. 10(12) Gy s(-1) during each pulse. Rapid energy deposition (< 50 0 ns) resulting in a considerable temperature increase in the surface material was accompanied by the formation of gaseous radiolysis produc ts. This led to a dramatic morphological change in which the surface r egion of the polymer was converted to a microcellular foam. Irradiatio n of polymers with high intensity ion beams appears to be a promising approach to the physical modification of the material surface. Publish ed by Elsevier Science Ltd.