Effects of Zig-Zag Hydrogen Bonding and Movable Cross-Linking on the Physical Properties of Poly(ether-thioureas)-Based Elastomer

It is important but challenging to overcome the trade-off in mechanical properties by simultaneously increasing the tensile strength and elongation of elastomers for many applications requiring diverse mechanical properties of polymeric materials. Here, we fabricated an elastomer that forms two types of physical bonds (hydrogen bond and host-guest interaction). The combination of poly(ether-thiourea) (TUEG) with zig-zag array of hydrogen bonds and polyrotaxane (PRX) with movable cross-linking junctions simultaneously increased the mechanical strength (tensile stress of 15 MPa) and elongation (tensile strain of 600%) of the elastomer. It was investigated that degradation of mechanical properties of polymer network against repeated deformation (10 times, tensile strain of 150%) was prevented owing to movable cross-linking junction of PRX. Therefore, this work presents a dual physically cross-linked elastomer having a short main chain (3k) with high tensile strength, tensile strain, and resilience.