Thermotropic Mesophases Enable Vitrification in Aliphatic Carboxylate Coordination Polymers
발표자
문회리 (이화여자대학교)
연구책임자
문회리 (이화여자대학교)
초록
내용
Vitrification of coordination polymers (CPs), particularly those based on carboxylate networks, remains rare despite their potential for creating functional hybrid glasses. Here, we report mesophase-driven vitrification in a family of carboxylate CPs, C-MgCnDC (n = 2–7, C stands for crystalline), based on aliphatic dicarboxylate linkers. Thermal dehydration triggers a conformational disorder in the aliphatic linkers and changes in carboxylate binding modes without cleavage of metal-ligand bonds, yielding a semicrystalline mesophase (desC-MgCnDC) of extended coordination networks. Continued heating induces a direct glass transition, producing mesophase-derived glasses. Notably, only the n = 7 derivative undergoes conventional melting, highlighting distinct mechanisms between mesophase- and melt-driven vitrification. The mechanical robustness of mesophase-derived glasses, attributed to chain entanglement, is contrasted with the softer nature of melt-quenched glass, in which the Mg–O backbone is partially dissociated. Our results demonstrate that ligand chain flexibility governs vitrification and cold crystallization pathways, establishing a mechanistic link to organic polymers. This mesophase-based strategy not only offers new design principles for fabricating hybrid glasses but also significantly broadens the chemical space of vitrifiable coordination networks beyond melt-processable materials.