The wetting, the adhesion to other objects, or the adhesion of paints is determined by the chemical and physical structure of a surface layer which is less than 1 nm thick. An analysis of chemically heterogeneous surface layers in that dimension is very challenging for modern analytical technology. Chemical functionalities have to be analyzed in a concentration in the order of 10-10 mol/cm2 before a background of the bulk material which is usually at least 104 times higher.
The combination of surface chemistry with instrumental methods creates powerful tools for the determination of functional groups on polymer surfaces. The idea behind this method called labelling or derivatization is that a certain functional group or a class of functional groups is reacted specifically with an agent that can be easily analyzed by an instrumental method.