“…Especially, topological constraint is one of the unresolved topics in polymer crystallization. , Solid-state NMR is anticipated to provide more detailed information about the impacts of connectivity, flexibility, and topological constraint on polymer crystallization at the molecular level. , In polymer glasses, the dynamic heterogeneity, as related to spatial nanoscale heterogeneity or dynamic fluctuations, is an important driver for glass formation, while the quantitative characterization of such dynamic heterogeneity still remain elusive, not to mention its effects on macroscopic viscoelastic observations. , In polymer processing, the chain entanglements are dominating the flow behaviors of polymer melts, while quantitative characterization of the heterogeneous distribution of entanglements is still challenging . In polymer theory, direct molecular-level experimental evidence from ssNMR is expected to drive the development of theoretical models for polymers with special topologies, such as ring, star, bottlebrush, comb, etc., which are fundamentally important for the design of polymers with complex architecture and thus unique rheological and mechanical properties . In polymer applications, fundamental understanding of ion-containing polymers for better design of polymer electrolyte applications is still deficient due to the intricate interplay of charges transport, ionic correlations, compositions, self-assembled nanostructures, and chain dynamics .…”