Wettability and Other Surface Properties of Modified Polymers

Surface wettability is one of the crucial characteristics for determining of a material’s use in specific application. Determination of wettability is based on the measurement of the material surface contact angle. Contact angle is the main parameter that characterizes the drop shape on the solid surface and is also one of the directly measurable properties of the phase interface. In this chapter, the wettability and its related properties of pristine and modified polymer foils will be described. The wettability depends on surface roughness and chemical composition. Changes of these parameters can adjust the values of contact angle and, therefore, wettability. In the case of pristine polymer materials, their wettability is unsuitable for a wide range of applications (such as tissue engineering, printing, and coating). Polymer surfaces can easily be modified by, e.g., plasma discharge, whereas the bulk properties remain unchanged. This modification leads to oxidation of the treated layer and creation of new chemical groups that mainly contain oxygen. Immediately after plasma treatment, the values of the contact angles of the modified polymer significantly decrease. In the case of a specific polymer, the strongly hydrophilic surface is created and leads to total spreading of the water drop. Wettability is strongly dependent on time from modification.