Abstract: Phase separation in polymer blends is a crucial method for polymer modification, which is covered in the course “Polymer Structure and Properties”. Different phase separation mechanisms result in distinct phase-separated structures, ultimately leading to various material properties. Understanding these mechanisms is essential yet challenging for students due to their abstract nature, making it a key focus in theoretical teaching. Based on years of teaching experience and research findings, we developed a process reproduction teaching method that demonstrates how phase diagrams of polymer blends are obtained. The teaching approach begins with basic binary mixture thermodynamics, then progresses to explaining thermodynamic behaviors of endothermic and exothermic binary systems at both low and high temperatures. Finally, it addresses complex binary blend thermodynamics and phase diagram construction. Using these phase diagrams, we explain two types of phase separation mechanisms under different compositions and temperatures. This teaching method has effectively helped students understand phase separation mechanisms, with some students successfully applying this knowledge to enhance ionic liquid gels.

Key words: Structure and properties of polymer, Phase separation mechanism of polymer blends, Process representation teaching method