Interfacial tension and acid-base approaches to polymer interactions

A significant correlation has been shown to exist between the interfacial t ension of polymer pairs and their acid-base pair interaction. The relations hip is inverse, with interfacial tensions decreasing as acid-base interacti ons increase. Interfacial tensions, frequently used as an indicator of poly mer compatibility, were measured by the breaking thread method at temperatu res in the vicinity of 200 degrees C. Acid-base pair interaction values wer e measured by inverse gas chromatography over wide temperature ranges. The observed correlation confirms the important contribution made by short-rang e, acid-base interactions to the observed value of interfacial tension and supports the prediction of equations based on fundamental definitions of su rface forces. A collateral finding of this work is the decrease of acid-bas e functionality with rising temperature for all polymers studied. (C) 2000 John Wiley & Sons, Inc.