초록 |
Crosslinked polymers containing dynamic covalent bonds have recently attracted considerable interests due to their reprocessability along with conventional thermoset-like features. However, their facile fabrication without need for extra monomer/polymer modification reactions is still a challenging issue. In this work, a branched PCL polyol containing a disulfide bond (PCLDS) was synthesized by ring-opening bulk polymerization of ε-caprolactone using 2-hydroxyethyl disulfide (HEDS) as an initiator. Then, PCL-DS/HEDS mixture with varying ratio was reacted with hexamethylene diisocyanate to construct a network bearing disulfide bonds (X-PCLDS/HEDS). Thermal and mechanical properties as well as reprocessing capability of the X-PCLDS-HEDS networks were investigated using DSC, DMA, and tensile test. The results revealed that the X-PCLDS/HEDS with a HEDS content of 7 wt% demonstrated a balanced mechanical and recycling properties as well as thermally triggered shape memory effects. |