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Fig. 12 Scaling of ʳ max (maximum adsorption) with N for polyacrylic acid on TiO 2 surfaces.
Taken from Mayoral and Nahmad-Achar ( 2014 )
ʓ max versus N is
plotted, the behaviour shown in Fig. 12 is obtained and the scaling function is
N and fitting each simulation to a Langmuir isotherm. When
ʓ max
N 4 / 5 . This result is in perfect agreement with the scaling theory in
the weak adsorption regime (de Gennes 1976 ), which indicates that at maximum
saturation
N 0 . 79
N 1 / 5
ʳ p = ʓ max N
,
(48)
where ʳ p is the number of monomers adsorbed in the flat plateau of the isotherm.
This implies
N 0 . 8 as obtained above.
Finally, another important example could be found in Gama Goicochea et al.
( 2014 ), where scaling laws for the viscosity ( ʷ ) and the friction coefficient ( μ )were
obtained by non-equilibrium DPD simulations.
N 4 / 5
ʓ max
=
6 Conclusions
The appropriate parametrisation for the relevant parameters in Dissipative Particle
Dynamics (DPD) simulations were presented. A clear methodology has been devel-
oped in the last few years to obtain the interaction parameters in great detail for realis-
tic systems, making possible the study of their dependence on concentration and tem-
perature. This work has proven to give predictions in accordance with experimental
results. Explicit examples of interfacial tension, adsorption isotherms, disjoining
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