| 초록 |
The highly self-healable polyurethane (hsPU) based on blend of conventional polyurethane (cPU) and functional polyimide (fPI) is synthesized and its self-healing properties and mechanical surface properties are examined. From the results of DSC and TGA experiments, cPU and fPI are completely miscible with each other and the thermal stability of hsPU is significantly improved on incorporation of fPI into cPU. By adding a small amount of fPI to cPU, hsPU exhibit better self-healing efficiency, faster self-healing kinetics, and, interestingly, more excellent surface hardness and modulus than cPU only. These outstanding properties are attributed to the strong supramolecular networks resulting from the intermolecular interactions between urethane groups and imide groups. FT-IR spectroscopy is performed to prove the effective self-healing mechanism of hsPU, and nanoindentation tester is used to compare the mechanical surface properties of hsPU and cPU after the self-healing process. |
