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Long polymer chains are admittedly beneficial for formation of flow‐induced shish‐kebabs, but up to now, the role of pressure, one major polymer processing parameter, in flow‐induced shish‐kebab is not touched. In the current work, bulk polyethylene (PE) and blend of 98 wt% PE and 2 wt% linear ultra‐high molecular weight polyethylene (LUHMPE/PE) were used as model polymers. Utilizing the pressuring and shearing device (PSD), the combined effect of pressure and long chains on flow‐induced shish‐kebab was revealed for the first time. Under a pressure of 50 MPa, there was no trace of shish‐kebab over the entire range of applied shear rates (0.5‐28.3 s−1). As the pressure increased to 75 MPa, shish‐kebab was induced by flow at 28.3 s−1 for PE, while shish‐kebab appeared in LUHMPE/PE blends at 15.7 s−1. Undoubtedly, the pressure significantly facilitated the formation of shish‐kebab and revealed a synergistic effect on flow‐induced shish‐kebab when cooperating with long chains. Our research not only demonstrates the importance of pressure conditions in flow‐induced crystallization, but also provides more valuable data for actual processing. [ABSTRACT FROM AUTHOR]

The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank-Kasper σ superlattices., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)