A way to better understand surface properties of carbon black fillers upon different polymers and coverages’ evolution
Executive summary
When modifying the surface of a solid material by impregnation, e.g. to obtain a polymeric layer on carbon black filler particles for improved compatibility, several questions usually arise:
Is the surface totally or only partially covered by the polymer? How much polymer is needed to cover the surface entirely? How does the choice of the polymer influence the surface properties?
Inverse Gas Chromatography at infinite dilution (IGC-ID) is a useful technique to evaluate the quality of the impregnation and to explore the surface interactions between the polymer and the carbon black filler. The method used here is based on the assessment of the surface properties displayed by the areas of carbon black particles left uncovered by the polymer deposits. Three types of surface properties are determined: the dispersive component of surface energy ( ), the nanoroughness defined by the morphological index (IM) and the specific interaction parameter (ISP). By the combination of these properties, it is possible to determine:
- the quality (i.e. the covering ratio) of the polymer deposition
- on the filler particles
- the quantity of polymer necessary to cover the whole surface area of the carbon black filler particles
- the energetic sites involved by the polymer adsorption
- the difference of adsorption behavior between two polymers
