Comparison of atmospheric-pressure plasma versus low-pressure RF plasma for surface functionalization of PTFE for biomedical applications

PTFE surface modifications have been realized using low-pressure RFGD, DBD and APGD in different atmospheres. Compared to the RFGD NH3 plasma, the DBDs operating in H-2/N-2 lead to similar surface concentrations of amino groups and similar surface damage, but with a much higher specificity. Both APGDs in H-2/N-2 and NH3/N-2 lead to lower concentrations of amino groups, but with similar specificity, and with lower surface damage than the RFGD treatment. A method is proposed to evaluate the efficiency of the different discharges for amine surface functionalization of PTFE, and it is concluded that the NH3/N-2 APGD discharge is the one that give the best results for an effective surface treatment.