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Wound dressings play a crucial role in wound treatment. Silk fibroin fiber membranes prepared via electrostatic spinning have generated medical wound dressings, exhibiting good biocompatibility with hemostatic, antimicrobial, and pro-healing properties. A pH-responsive ZnS/SF composite fiber membrane was prepared by loading zinc sulfide (ZnS) nanoparticles into a silk fibroin fiber membrane via in situ polymer matrix growth. The composite fiber membranes produced under the optimized conditions were successfully loaded with nanoscale ZnS particles. They had a dense reticular structure and high-water absorption with good biocompatibility and hemostatic properties. Upon exposure to an acidic microenvironment at the wound site, ZnS reacted with H+, giving a sustained release of hydrogen sulfide (H2S) and zinc ions (Zn2+), possessing strong bactericidal activity and pro-cell migration effects, facilitating angiogenesis. The composite fiber film is effective in helping to further promote wound healing when it is used as a wound dressing. This pH-responsive multifunctional ZnS/SF composite fiber membrane has potential applications in medical wound dressings. [ABSTRACT FROM AUTHOR]

To study the effect of the melt-draw ratios (MDRs) on the structure and properties of the poly(4-methyl-1-pentene) (PMP) film, the crystal structure evolution and mechanical properties of the PMP film with an MDR of 40–160 were characterized using scanning electron microscopy, differential scanning calorimetry, wide-angle X-ray scattering, and mechanical test. The results show that with the increase of MDR, the spherulite to platelet transition occurs in the PMP. When the MDR exceeds 100, a parallel platelet structure appears. Due to the side chains, with the increase of MDR, the distribution density of tie chains in PMP decreases and the entanglement density of amorphous chains increases. This leads to a decrease in the yield strength and the strain hardening becomes noticeable. Although the crystalline network becomes loose due to the decrease in tie chain density, the elastic recovery (ER) value still increases with the increase of MDR. This result indicates that the entanglement density of the amorphous region greatly contributes to the ER.

Responsive hydrogels hold great promise for applications such as biological tissue engineering, controlled drug release, soft actuators, and intelligent sensors. However, the design and construction of robust responsive hydrogels using a simple method remains a significant challenge. Herein, a non‐covalently crosslinked responsive hydrogel was constructed by introducing carboxyl‐Zr4+ metal coordination to the hydrophobic association network of P(AA‐co‐LMA) hydrogel through a facile one‐pot polymerization method. The incorporation of multiple reversible interactions, including hydrogen bonding, metal coordination, and hydrophobic association, resulted in a responsive hydrogel with exceptional mechanical strength (≈2.92 MPa), outstanding flexibility (elongation>1000%), and rapid response to pH alterations. Furthermore, the hydrogel also presented good ionic conductivity due to the abundant movable ions, as well as high sensitivity and stability. As application demonstrations, the supermolecular hydrogel had been successfully used in actuating and strain sensing. This work establishes an effective design strategy for creating tough and multifunctional responsive hydrogel. [ABSTRACT FROM AUTHOR]