ESTIMATION OF MISCIBILITY OF POLYMER BLENDS USING THE SOLUBILITY PARAMETER CONCEPT

A number of approaches for the prediction of polymer-polymer miscibility have been reviewed. Much work, reported in the literature, has been directed towards understanding the behaviour of polymer and copolymer mixtures using polymer interaction parameters based on empirical or semi-empirical values. These values often require extensive experimental data for their calculation and tend to lack general applicability. A new concept is presented here that is based upon the utilization of the individual component contributions to the solubility parameter. The development of a 'miscibility parameter', which describes the interaction of polymer repeat units, provides semi-quantitative values which relate the three basic interactive forces, i.e. dispersive, polar and hydrogen bonding. This results in a generalized scheme applicable to large classes of systems. The validity of the miscibility parameter is tested against other methods described in the literature with good results.