Formation of Poly(ε-caprolactone) Networks via Supramolecular Hydrogen Bonding Interactions
In this contribution, we reported a novel approach to crosslink poly(ε-caprolactone) (PCL) via supramolecular hydrogen bonding interactions. First, a series of octa-armed poly(ε-caprolactone) stars with polyhedral oligomeric silsesquioxane (POSS) cores were synthesized via the ring-opening polymerizations. Thereafter, the arm ends of organic-inorganic star-shaped PCLs were reacted with 2-(6-isocyanatohexylaminocarbonylamino)-6-methyl-4[1H]-pyrimidinone to obtain 2-ureido-4[1H]-pyrimidone (UPy)-terminated PCL stars. Notably, the UPy-terminated PCL stars were physically crosslinked, which was evidenced by means of dynamic mechanical thermal analysis (DMTA) and rheological analysis. Owing to the formation of the physically-crosslinked networks, the organic-inorganic PCL stars displayed significant shape memory properties with about 100% of shape recovery, which was in marked contrast to the PCL stars without UPy termini.
KeywordsPOSS PCL Physical crosslinking Shape memory properties
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This work was financially supported by the National Natural Science Foundation of China (Nos. 51133003, 21274091, and 21774078).
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