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Adsorptive separation of propyne/propylene (C3H4/C3H6) is a crucial yet complex process, however, it remains a great difficulty in developing porous materials that can meet the requirements for practical applications, particularly with an exceptional ability to bind and store trace amounts of C3H4. Functionalization of pore‐partitioned metal–organic frameworks (ppMOFs) is methodically suited for this challenge owing to the possibility of dramatically increasing binding sites on highly porous and confined domains. We here immobilized Lewis‐basic (−NH2) and Lewis‐acidic (−NO2) sites on this platform. Along with an integrated nature of high uptake of C3H4 at 1 kPa, high uptake difference of C3H4−C3H6, moderated binding strength, promoted kinetic selectivity, trapping effect and high stability, the NH2‐decorated ppMOF (NTU‐100‐NH2) can efficiently produce polymer‐grade C3H6 (99.95 %, 8.3 mmol ⋅ g−1) at room temperature, which is six times more than the NO2‐decorated crystal (NTU‐100‐NO2). The in situ infrared spectroscopy, crystallographic analysis, and sequential blowing tests showed that the densely packed amino group in this highly porous system has a unique ability to recognize and stabilize C3H4 molecules. Moving forward, the strategy of organic functionalization can be extended to other porous systems, making it a powerful tool to customize advanced materials for challenging tasks. [ABSTRACT FROM AUTHOR]

Natural silk fibroin nanofibers (SNF) have recently attracted great attention in the field of biomaterials due to their excellent biocompatibility, outstanding mechanical properties, and biomimetic nanostructures. However, the poor structural stability of SNF assembly in aqueous conditions remains a major obstacle to their biomedical application. In this work, SNF scaffolds with extracellular matrix‐mimicking architecture and tunable properties were developed by using a small amount of konjac glucomannan (KGM) as a physical adhesive. Fourier transform infrared spectroscopy (FTIR) results revealed that KGM facilitated the formation of hydrogen bond networks between SNF as well as nanofibers/polysaccharide molecules, thereby reinforcing the interconnectivity between SNF. The water stability test showed that SNF scaffolds exhibited good structural stability in water when the mass ratio of KGM/SNF reached 2.5/100. Raising KGM content significantly enhanced the compression strength, modulus, and swelling ratio of the porous scaffold. Whereas, the nanofibrous morphology and porosity of the scaffolds were significantly sacrificed as KGM content exceeded 10% as evidenced by scanning electron microscopy (SEM) results. In vitro, cytocompatibility results also demonstrated the excellent biocompatibility of the biomimetic nanofibrous scaffolds, and the high porosity significantly enhanced cell viability. These results suggest that KGM‐reinforced SNF scaffolds may serve as promising candidates for biomaterial applications. [ABSTRACT FROM AUTHOR]

Chitosan (CS) fibers have been applied in various fields due to their biocompatibility, biodegradability, and antibacterial properties. However, weak mechanical properties remain as obstacles to further applications. Silk nanofibrils (SNFs) extracted from natural silk fibroin fibers preserve outstanding mechanical properties at the nanoscale, which are expected to impact structural programming and mechanical reinforcement for CS fibers. In this study, wet‐spun CS/SNFs composite fibers were continuously collected from NaOH/ethanol coagulation. Scanning electron microscope (SEM) results showed that SNFs were uniformly distributed in the CS matrix, and obvious orientation was observed when the mass ratio of SNF/CS was 75/100. Tensile tests showed that the introduction of SNFs significantly enhanced the mechanical properties of CS fibers when the mass ratio of SNF/CS was more than 25/100. With the increasing of SNF content, the tensile strength gradually increased, and the tensile strength and modulus could be increased 2.9 times and 3.5 times, respectively, when 100% SNF was added. The improvement of mechanical properties was partially attributed to hydrogen bonding between SNF filaments and CS, which was confirmed by FTIR and XRD results. This study provides a facile and eco‐friendly method to spin CS fibers with enhanced mechanical properties and a hierarchical structure. [ABSTRACT FROM AUTHOR]