The determination of polymer/polymer interaction parameters (χ) from melting point data is critically reviewed with emphasis on two major areas. The first concerns variations of morphology with blend composition which can restrict attempts to calculate χ if nonequilibrium melting points are used. An equation is presented that relates the experimentally observed melting point change upon blending to the thermodynamic melting point depression and a morphological term that accounts for changes in lamellar thickness. Other morphological factors such as crystalline perfection and size are discussed. The second area of interest involves processes such as lamellar thickening during thermal analysis that can seriously impair determination of “true” crystalline melting points. Finally, methods for directly determining blend equilibrium melting points are discussed.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry