The flexible segment adjusted gelation of the aliphatic polycarbonates: Preparation, mechanical properties, and self-healing behavior

Abstract

Many methods are used to improve the mechanical properties of hydrogels, but it is still challenging to generate comparable to natural hydrogels, let alone synchronously give it excellent self-healing properties. Herein, we synthesize a novel type of the aliphatic polycarbonate hydrogel with the above advantages. In this work, the ring-opening polymerization of 2-methyl-2-benzyloxy carbonyl propylene carbonate (MBC) and 1, 3-trimethylene carbonate (TMC) are initiated by the hydroxyl group of methoxy poly(ethylene glycol) (mPEG113, Mn = 5000). The effect of the TMC as flexible segments on the structure, mechanical properties, and self-healing behavior of the obtained materials is systematically studied. The swelling ratios of the obtained gels in water are enhanced as the content of the monomer TMC increases. The self-healing ability of the materials is drove by the hydrogen bonds and the hydrophobic associations to heal the fracture interfaces. The obtained gels exhibit outstanding mechanical properties and excellent ability of self-healing at room temperature. Both of these abilities can be adjusted by the variation of the TMC flexible segment. Thus, we provide a novel strategy for the fabrication of modified tough hydrogel, which will expand the modification field of hydrogels.