Influence of fiber surface purity on wicking properties of needle-punched nonwoven after oxygen plasma treatment

Polyester and meta-aramid nonwoven samples were treated at reduced pressure in a radiofrequency oxygen plasma for between 5 and 30 seconds. The hydrophilic effect of the plasma treatment was assessed by three consecutive vertical wicking tests on each sample. The influence of cleaning of the fiber surface before as well as after the plasma treatment was determined. The presence of fiber surface additives had a positive influence on first-time wicking. On the other hand, when the layer of surface additives is plasma treated rather than the fiber polymer surface, the treatment effect is easily washed away. Log(time) wicking curves and summed wicking height plots are introduced as a means to help the interpretation of wicking data.