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In this work, SMPUs with non-planar ring structures in the hard segments display a low degree of phase separation but excellent shape recoverability (shape recovery rate ∼99% with 500% strain). The accepted wisdom is that there are two criteria for SMPUs possessing good shape recoverability: (i) high degree of phase separation forming physical crosslinks; (ii) strong physical interactions between hard segments which keep physical crosslinks stable under external stress. However, our results are completely against the accepted wisdom since the asymmetrical non-planar ring structures will depress the micro-phase separation and physical interactions in the hard phase. Thus, the excellent shape recovery could not be attributed to the phase morphology. Based on such results, single molecule force spectroscopy was adopted to study the properties of single polymer chains with non-planar ring structures. We …