Wettability control of polystyrene by ion implantation

Abstract

The permanent effects of ion implantation on the improvement of wettability of polystyrene is investigated in relation to ion species and fluences. The He+, Ne+, Na+, N+2, O+2, Ar+, K+ and kr+ ion implantations were performed at energies of 50 and 150 keV at room temperature. The fluences ranged from 1 × 1015 to 1× 1017 ions/cm2. The results showed that the contact angle of water for Na+ and K+ implanted polystyrene decreased from 87° to 0°, as the fluences increased to 1 × 1017 ions/cm2 at an energy of 50 keV. The contact angle for Na+ and K+ implanted polystyrene did not change under ambient room conditions, even when time elapsed. However, the contact angle for He+, C+, O+, Ne+, N+2, O+2, Ar+, and Kr+ ion implanted specimens decreased slightly immediately after ion implantation. Results of X-ray photoelectron spectroscopy showed that the increase in the Na content in the surface of Na+ implanted specimens were observed with increasing fluence. It is concluded that permanent improvement in wettability was caused by doping effects rather than by radiation effects from Na+ and K+ ion implantation.