The roughness data for native starch (S) and PC treated starch (S/PC) at different temperatures or Blebbistatin treated.SurfaceRa (μm)Rq (μm)Rz (μm)Rt (μm)S 25 °C1.842.2710.6811.14S 25 °C plasma1.822.2410.5411.07S 37 °C1.411.7610.3111.99S 37 °C plasma1.411.7610.311.88S 60 °C0.881.128.429.64S 60 °C plasma0.250.366.146.21S/PC 25 °C1.301.6010.8111.90S/PC 25 °C plasma1.251.5710.7911.80Full-size tableTable optionsView in workspaceDownload as CSV
The increase of attractive interactions between both components causes the formation of more and more tightly packed monolayers characterized by lowering values of the roughness parameters. Therefore, such condensed films are less permeable for the probe liquids used for the contact angle measurements. Based on these results one may conclude that the surface free energy of the examined surfaces, is determined to some extent by the roughness of their surface. Some other factors must influence these surface parameters, such as the presence of unsaturated bonds in molecules and the phase state in which these films exist, therefore FTIR spectra can be useful. During gelatinization the intensity of some bands increases and new peaks can appear, hence the changes of hydrophilicity can be observed from the FTIR spectra differences described in the next section.