Mesh infection is a major complication of hernia surgery after polypropylene (PP) mesh implantation. Modifying the PP mesh with antibacterial drugs is an effective way to reduce the chance of infection, but the hydrophobic characteristic of PP fibers has obstructed the drug adhesion. Therefore, to prepare antimicrobial PP mesh with a stable drug coating layer and to slow the drug release property during the hernia repair process has a great practical meaning. In this work, PP meshes were coated by bio-inspired polydopamine (PDA), which can load and release levofloxacin. PP meshes were activated with cold oxygen plasma and then plasma activated PP fibers were coated with PDA. The PDA coated meshes were further soaked in levofloxacin. The levofloxacin loaded PP meshes demonstrate excellent antimicrobial properties for 6 days and the drug release has lasted for at least 24 h. Moreover, a control PP mesh sample without plasma treatment was also prepared, after coating with PDA and loading levofloxacin. The antimicrobial property was sustained only for two days. The maximum inhibition zone of PDA coated meshes with and without plasma treatment was 12.5 and 9 mm, respectively. On all accounts, the modification strategy can facilely lead to long-term property of infection prevention.

Mesh infection is a major complication of hernia repair. After knitted mesh implantation, bacteria can grow within textile structures causing infection. In this work, polypropylene (PP) mesh devices were two-step grafted with hexamethylene diisocyanate (HDI) and β–cyclodexrins (CD) and then loaded with suitable antimicrobial levofloxacin HCL for hernia mesh-infection prevention. First, oxygen plasma was able to create surface roughness, then HDI was successfully grafted onto PP fiber surfaces. Afterwards, CD was covalently grafted onto the HDI treated PP meshes, and levofloxacin HCL (LVFX) was loaded into the CD cavity of the modified meshes. The modified devices were evaluated for sustained antibiotic properties and drug-release profiles in a phosphate buffer, and sustained drug release was observed between interfaces of meshes and aqueous environment. The antibiotic-loaded PP mesh samples demonstrated sustained antibacterial properties for 7 and 10 days, respectively, against both Gram-negative and Gram-positive bacteria. The CD-captured levofloxacin HCL showed burst release after 6 h but later exhibited sustained release for the next 48 h. Among all samples, the modified mesh LVFX-6 was more stable and showed more sustained drug release and could be employed in future clinical applications.

An ideal hernia mesh is one that absorbs drugs and withstands muscle forces after mesh implantation. Polypropylene (PP) mesh devices have been accepted as a standard material to repair abdominal hernia, but the hydrophobicity of PP fibers makes them unsuitable to carry drugs during the pre-implantation of PP meshes. In this study, for the first time, one-step functionalization of PP mesh surfaces was performed to incorporate bio-inspired polydopamine (PDA) onto PP surfaces. All PP mesh samples were dipped in the same concentration of dopamine solution. The surface functionalization of PP meshes was performed for 24 h at 37 °C and 80 rpm. It was proved by scanning electron microscopic (SEM) images and Fourier Transform Infrared Spectroscopy (FTIR) results that a thin layer of PDA was connected with PP surfaces. Moreover, water contact angle results proved that surface functionalized PP meshes were highly hydrophilic (73.1°) in comparison to untreated PP mesh surfaces (138.5°). Thus, hydrophilic PP meshes with bio-inspired poly-dopamine functionalization could be a good choice for hernia mesh implantation.

Ultra-high-molecular-weight polyethylene (UHMWPE) fabric is widely used in many fields due to its excellent properties such as high modulus, high strength, and impact resistance. However, its high flammability prevents its application in high-temperature environments. Therefore, it is important to develop multifunctional UHMWPE fabric to meet its different requirements in firefighting, military, and other scenarios. Here, we have prepared a durable flame-retardant superhydrophobic UHMWPE fabric by a simple coating method. A polyurethane solution mixed with decabromodiphenylethane and antimony trioxide is scraped on the surface of the fabric to form a coating, which endows the fabric with flame retardancy. The sprayed fluorinated hydrophobic agent provides superhydrophobic properties to the fabric. It is worth mentioning that plasma pretreatment greatly improves the adhesion properties of the coating by stimulating the active groups on the surface of the fabric. Tests have shown that the adhesion between the coating and the surface of the plasma-treated UHMWPE fabric has been greatly improved. The limiting oxygen index value of the coating UHMWPE fabric has increased by 90%, and it immediately extinguishes after leaving the flame, demonstrating excellent flame retardancy. The contact angle between its surface and water reaches 156°, exhibiting excellent superhydrophobicity and self-cleaning properties. This study provides a simple, convenient, and effective method for the development of multifunctional UHMWPE fabric, greatly expanding its application scenarios and providing ideas for future development.

High-strength nanofiber yarns exhibit pronounced nonlinear tensile responses arising from their hierarchical fibrous architecture, yet compact constitutive descriptions remain limited. Here, high-strength polyacrylonitrile nanofiber yarns were prepared by post-drawing as-spun yarns above the glass transition temperature, and their aligned, stacked morphology was confirmed by scanning electron microscopy. Monotonic tensile tests at different loading rates were used to quantify the rate-dependent stress–strain response. The tangent modulus derived from the tensile curve varied strongly with strain, confirming clear deviation from linear viscoelasticity. To capture this behavior, two effective models were established: a modified nonlinear three-element model and a structural four-element model incorporating a nonlinear elastic contribution. Closed-form stress–strain expressions were derived for constant strain-rate loading and fitted to experimental data using nonlinear regression. Both models reproduced the measured tensile curves with high accuracy over the investigated loading-rate range, with correlation coefficients close to unity and low fitting errors. The identified parameters were highly consistent between formulations, indicating functional equivalence for the present monotonic tensile dataset. These results provide a compact framework for characterizing and designing hierarchical polymer nanofiber yarns.