Characterisation of the surface Lewis acid–base properties of the components of pigmented, impact-modified, bisphenol A polycarbonate–poly(butylene terephthalate) blends by inverse gas chromatography–phase separation and phase preferences

Inverse gas chromatography was used to study the surface Lewis acid–base properties of the major components of pigmented, impact-modified, polycarbonate–poly(butylene terephthalate) blends. An investigation of the Lewis acid–base interactions in these polymeric systems has been carried out, based on the values determined for the surface Lewis acidity constant (Ka), surface Lewis basicity constant (Kb) and on the chemical and physical structure of the materials involved. This analysis provided the rationale for an interpretation of the phase separation and the phase preference that exist in these polymer blends, and of the consequences to their physical and mechanical properties.