Surface reactions of vapor phase titanium atoms with halogen and nitrogen containing polymers studied using in situ X-ray photoelectron spectroscopy and atomic force microscopy

The surface reactions of vapor phase Ti with polytetrafluorethylene (PTFE), polyvinylchloride (PVC) and nitrogen-modified polyethylene (PE) have been studied using in situ X-ray photoelectron spectroscopy (XPS) and ex situ atomic force microscopy (AFM). Titanium reactions with PTFE and PVC surfaces lead to the simultaneous formation of a titanium halide salt and TiC. Titanium reactions with both PTFE and PVC also produced significant morphological changes at the polymer surface. During Ti metallization of PTFE, defluorination did not produce any CF or CF3 species normally observed during defluorination reactions of metal atoms with PTFE. The amount of titanium fluoride present at the metal–polymer interface was enhanced by post-metallization X-ray irradiation. Results on the Ti surface reactions are also compared and contrasted with Fe and Cu reactivity with PTFE and PVC. The reactions of Ti with nitrogen-modified PE lead to the simultaneous formation of TiN and TiC. Experimental evidence, however, suggests that the different nitrogen containing functional groups present in the nitrogen-modified PE were not equally reactive towards Ti metallization.