| 초록 |
Herein, we introduce highly self-healable ABA-type block copolymers by chemical reaction of poly(2-(N-phthalimido) ethyl methacrylate) (PNPEMA) and polyurethane (PU). The 2-hydroxyethyl phthalimide is reacted with methacryloyl chloride in the presence of triethylamine to from the 2-(N-Phthalimido) ethyl methacrylate (NPEMA). Subsequently, RAFT polymerization of the NPEMA previously synthesized is performed at 70 ℃ for 5 hours. Then, by using H2O2. The dithiobenzoate end-groups of PNPEMA are substituted with hydroxyl groups. Polyurethanes with isocyanate groups at both chain ends are synthesized via condensation reaction using ethylene glycol and isophorone diisocyanate (IPDI). Finally, ABA-type block copolymers are synthesized by reaction between end-groups of PNPEMAs and PUs. The triblock copolymers are characterized by using GPC and NMR. In addition, the self-healing properties of the block copolymers are characterized by using DMA and DSC experiments. |
