Modification of wetting properties of CR39 by plasma source ion implantation

Plasma source ion implantation (PSII), a hybrid implantation technique between ion beams and immersion plasmas has been used to modify CR39 surfaces for improved wettability providing both advancing (theta(a)) and receding (theta(r)) contact angles below 5 degrees. The modifications brought to the polymer surface structure have been characterized by X-ray photoelectron spectroscopy (XPS) and its combination with chemical derivatization (CD-XPS). Oxygen desorption has been observed in spite of the very hydrophilic surfaces. C(1s) XPS peak has been displaced toward greater energies, while the opposite has been found for O(1s), both involving new components and strong modi. cations after ion implantation treatment. Strong evidences about the formation of new chemical functions, like -OOH, -COOH and C=C, have been found and have provided an explanation for the increased wettability. (C) 2008 Elsevier B. V. All rights reserved.