Calculation of dispersion force interactions between colloidal particles in butan-1-ol

Calculation of dispersion force interactions between colloidal particles of Graphon, polystyrene and polytetrafluoroethylene dispersed in butan-1-ol using the Lifshitz method is described. The complex frequency-dependent permittivity has been estimated from spectroscopic data for the colloidal materials and has been used to assess the frequency dependent contributions to the Hamaker function over a range of particle separation distances. The Hamaker functions for interaction between Graphon particles, and between Graphon and polystyrene particles are shown to be insensitive to the precise value of the static permittivity of Graphon. In contrast the dispersion force interaction between Graphon and PTFE is markedly dependent on the value of Iµ0(Graphon) and may under some conditions be repulsive.