Compatibilization criteria and procedures for binary blends: A review

Polymer blends have been widely studied for the property improvement of commercial polymers. Most polymer blends, however, present coarse and unstable phase morphologies and poor adhesion at the interface, which is due to their immiscibility. Such problems have often been overcome with the addition of a proper compatibilizer that is able to modify the interfacial condition. In this way, it is possible to control the morphology of the material and the interphase adhesion in an appropriate manner to achieve an effective stress transfer within the blend. Compatibilization criteria and procedures, either by adding a third component ("compatibilizer") or by inducing in situ chemical reactions between blend components, are reviewed. Some theoretical aspects of compatibilization processes have also been considered, giving examples of experimental consistency. The authors also report on the different compatibilizers used for several pairs of immiscible polymers with indications of their action to promote homogenization between phases.