Abstract
The investigations presented were aimed at a description of the structure of the adsorbed layers of polyethylene glycol (PEG) on the surface of Al2O3. This was obtained from measurements of the adsorption heat of PEG macromolecules as well as of 1,2-dimethoxyethane (C4H10O2) and tetraethylene glycol dimethyl ether (C10H22O5), i.e. low-molecular weight compounds constituting the monomers forming the PEG chain.
The results allowed the fraction of polymer segments bonding directly to the Al2O3 surface to be estimated. Other information obtained from calculations based on the Scheutjens–Fleer theory included the distribution of chain segment conformations as trains, loops and tails, together with a determination of some structural changes and the sizes of PEG macromolecules as they moved from the bulk solution to the solid phase surface. The thickness of the adsorbed macro-molecular polymer layers on the alumina surface was also determined. All these data enabled an approximate description to be made of the polymer chain structure at the Al2O3–polymer solution interface.