A MODEL FOR POLYBUTADIENE COATINGS ON POROUS SILICA

Non-wetting viscous liquids such as oligobutadiene prefer ''active'' s ites such as pores during the process of physisorption. Thus, polybuta diene (PBD) coatings on porous silica do not result in a homogeneous p olymer film but in an inhomogeneous loading where the bulk polymer is mainly sited in the pores of the silica. An increasing polymer loading leads to increasingly filled pores instead of a thicker polymer film. We cannot exclude the possibility that most of the surface is covered at least with a thin polymer film since the chromatographic behaviour is relatively good for polypeptides, which are highly susceptible to the silanol groups of silica.