Dorris and Gray

Assuming that the work of adhesion between a saturated hydrocarbon and a second phase Is equal to the free energy of desorption per mole of CHj groups, Dorris and Gray (5 ) proposed the equation for the estimation of the London component of the surface free energy of the adsorbent ... 

This parameter is independent on the chosen reference state of the adsorbed molecule. According to Dorris and Gray [22] ... 

There are three accepted methods of determining values at infinite dilution and which were published by Dorris and Gray [98], Schultz et al. [95] and Donnet et al. [99]. 

Extending the approach of Dorris and Gray [6] to the PDMS oligomers, we may calculate an increment of free enthalpy of adsorption corresponding to a monomer unit, AGa, according to ... 

However, some authors have stressed the difficulties associated with the determination of the molecular area, especially for non-spherical molecules such as straight alkanes. To avoid the problems derived from the molecular area, Dorris and Gray [26] considered the adsorption characteristics of single methylene groups in the n-alkane probes. By defining the increment in free energy of adsorption per - CH2- unit ... 

The validity of this approach has established on the basis that IGC and wettability measurements lead to approximately the same yf value for poly(ethylene tereph-thalate) [28]. Furthermore, Dorris and Gray stated that the molecular area could be an adjustable parameter. 

The dispersive component of the surface energy 7 can be calculated from the retention time obtained from iGC measurements of a series of n-alkane probes injected at infinite dilution (concentration within the Henry"s portion of the adsorption isotherm) [8]. Two approaches are used for the evaluation of these dependencies, the first one according to Schultz and co-workers [9] Equation 4.1 and the second one according to Dorris and Gray [10] Equation 4.2 ... 

D. Klemm, E Kramer, S. Moritz, T. Lindstrom, M. Ankerfors, D. Gray, and A. Dorris, Angewandte Chemie International Edition, 50, 5438,2011. 

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