Surface modification of polymer films by pulsed oxygen plasma

The surfaces of three kinds of polymer were treated using pulsed oxygen plasma: poly(ether ether ketone) (PEEK), liquid crystalline polymer (LCP), and linear-low-density polyethylene (L-LDPE). Also using pulsed oxygen plasma, oxygen functional groups were introduced on polymer surfaces. The effects of oxygen functional group introduction were investigated to elucidate whether any differences exist in the manner of introduction of oxygen functional groups on the polymer surface, arising from differences in polymer structures. The introduction of oxygen functional groups formed hydrophilic polymer surfaces. Fewer oxygen functional groups were introduced on PEEK and LCP surfaces by pulsed plasma treatment than by continuous oxygen plasma. On the other hand, many oxygen functional groups were introduced on L-LDPE surfaces than by continuous oxygen plasma. Reasons for different attachment of oxygen functional groups by pulsed oxygen plasma processing on polymer surfaces were discussed.