Radiation damage and wettability change of low energy C+ implanted polytetrafluoroethylene

The surface modification of polytetrafluoroethylene (PTFE) was carried out by carbon ion implantation. The influence of implantation parameters was in vestigated by varying ion dose over a wide range. The samples were implante d with 20 keV carbon ion with doses from 5 x 10(15) to 5 x 10(17) ions cm(- 2), and examined by ESCA, XRD, SEM, and wettability. Five chemical bonds we re formed on the surfaces of as-implanted samples, and their content change d as a function of ion dose. The crystallinity of the as-implanted samples increased gradually with increasing ion dose. Various radiation damage stru ctures were observed. The values of droplet contact angle of the as-implant ed samples increased gradually with increasing ion dose, and was very sensi tive to the environmental humidity under which the droplet contact angle wa s measured. The experimental results show that the surface chemical bond, c rystallinity, morphology, and wettability of as-implanted PTFE samples are closely dependent on the carbon ion dose. (C) 2001 Elsevier Science B.V. Al l rights reserved.