| 초록 |
1,4:3,6-dianhydrohexitol (DAH) isomers, such as isosorbide (ISB), isomannide (ISM), and isoidide (ISD) are heterocyclic diols derived from renewable resources. The difference among DAH isomers is the position of two hydroxyl groups, providing variations in physical and chemical properties. The incorporations of DAHs to polyurethanes are expected to improve the glass transition temperature and mechanical properties due to its rigidity and chirality. In this study, polyester polyols were synthesized via polycondensation reaction of DAH (ISB or ISM) and diacid. Polyurethane (PU) prepolymers were prepared from DAH based polyester polyols and 4,4-diphenyl methane diisocyanate (MDI) and chain extended with DAH to get PU elastomers. It was found that the urethane groups formed by the reaction of DAH and MDI became reversible at elevated temperatures and imparted self-healing properties. Thermal and mechanical properties of the PUs were affected by the different structures of DAH isomers. |
