Figure 7.

Thermoplastic elastomers by switch catalysis, exploiting the rigid structures of polyesters prepared by ROCOP as hard domains for physical cross-linking and amorphous elastomeric polyesters prepared by lactone ROP. (a) Switch catalysis illustration of ε-decalactone ROP (green) and ROCOP of phthalic anhydride (red)/cyclohexene oxide (blue). (b) Conversion–time plot of switch reaction monitored at regular intervals by ¹H NMR spectroscopy. (c) Schematic illustrating the stretching and relaxing of triblock copolymer. (d) Stress–strain plot of elastomer undergoing stretching and relaxing with minimal hysteresis loss over 10 cycles.⁷² Image adopted from ref (72) with permission from The Royal Society of Chemistry.