Polypropylene surface modification with stearyl alcohol ethoxylates to enhance wettability

Stearyl alcohol ethoxylated additives were melt‐blended in polypropylene (PP) films, and the characteristics of the modified films were investigated. The melt blending of stearyl alcohol ethoxylates improved the hydrophilicity of the PP films through additive surface segregation. Surface specific techniques, such as X‐ray photoelectron spectroscopy and time‐of‐flight secondary‐ion mass spectrometry, were used to study the surface compositions of the samples modified with ethoxylated additives. This revealed that the surface concentrations of the additives were significantly higher than the bulk concentrations in all samples. In addition, the surface compositions of the additive‐modified samples continuously changed, even after the films were fully solidified. We also found that the resulting surface characteristics were very dynamic, so the melt‐additive‐containing polymer surfaces responded to water exposure, and their surface properties and morphologies were altered as a result.