Macromolecular Materials and Engineering最新文献

Liquid-solid triboelectric nanogenerator (LS-TENG) harvests energy efficiently while eliminating wear issues associated with solid-solid TENG. However, the effect of ions or charges in the liquid on output performance needs further examination. In this work, the impact of fluorine and copper ions introduced through deionized water with sodium fluoride (DI-NaF) and deionized water with copper sulfate (DI-CuSO₄) solution on the output voltage, charge and current of a tubular LS-TENG with polytetrafluoroethylene (PTFE) and Nylon as solid materials is examined. The results indicate that fluorine and copper ions have opposite effects on PTFE and Nylon LS-TENG's output. The fluorine (F⁻) ions enhance the triboelectric effect and charge transfer in Nylon LS-TENG, increasing output, while they hinder the charge transfer process in PTFE LS-TENG, consequently decreasing its output. Conversely, the copper (Cu²⁺) ions have a positive effect on the output of PTFE LS-TENG and a detrimental effect on Nylon LS-TENG's output. Moreover, the results indicate that LS TENG's output performance depends on the charges of solid and liquid triboelectric materials. Thus, this study provides insights into material-ion interaction in LS-TENG and underscores the importance of triboelectric material selection for optimizing output performance.

The textile industry comprises technologies that transform synthetic or natural fibers into yarn, cloth, and felt for manufacturing clothing, upholstery, and household linens. The major public health threat in tropical and subtropical countries is mosquito-borne malaria. Nowadays, the demand for insect repellent-based textiles is continuously rising, as they are used for protection against diseases transmitted by mosquitoes. The present work reviews studies on the fabrication of insect repellent containing electrospun polymeric nanofibers as principal tools for protecting people against mosquito bites. Electrospinning technology is a remarkably facile technique for fabricating polymeric nanofiber devices. The technique is outlined and elucidated. The performance of insect repellent-based polymeric nanofibers against mosquitoes is carefully reported and comprehensively reviewed in-depth. Furthermore, the progress made on the mathematical modeling of the release rate of repellents through polymeric nanofiber devices is reviewed. The reviewed studies demonstrate that repellents can be released slowly from electrospun nanofibers, increasing the product's protection period against insects. The reviewed works suggest that electrospinning technology has led to an effective and facile methodology for fabricating functional nanofiber textiles with insect repellent. The reviewed studies showed that product-based repellents can be effective not only against malaria but also against other mosquito-borne diseases.

Membrane osmotic distillation (OD) is applied in this work for the partial dealcoholization of beer (5.2 v/v% alcohol content) to diminish its ethanol content by around 50% giving rise to a low alcohol beer. A compromise is sought between the low alcoholic degree achieved and beer sensory properties. Moreover, the feasibility of the membrane OD process intensification is studied thanks to its combination with membrane pervaporation (PV). Two successive PV stages, one hydrophobic and the other hydrophilic, allow the production of recycled water (with less than 0.5 wt% ethanol) for the membrane OD operation and bioethanol (99% ethanol) as valuable byproduct.

Macromol. Mater. Eng. 2024, 309, 2300273

In the list of authors at the beginning of the article, we misspelled the name of the first author as “Jinqin Wang”, which is incorrect.

The correct spelling should be “Jinqing Wang”.

We apologize for this error.

The first author's first name has been corrected in the article itself: https://doi.org/10.1002/mame.202300273

Three-dimensional (3D) printing is an innovative manufacturing method for preparing designer materials with complex geometries. However, there are very few studies on the fabrication of antimicrobial polymer materials suitable for use in everyday clinical objects, via 3D printing. In this work, an antibacterial polymer material is prepared by blending polyamide 11 (matrix), a high-performance engineering thermoplastic, and a styrene maleimide copolymer with pendant quaternary amine moieties, and the blend 3D printed via selective laser sintering. The quaternary amine functionalities confer permanent antimicrobial properties. Blend properties are studied prior to printing via differential scanning calorimetry, powder X-ray diffraction, and FTIR spectroscopy. Additionally, the mechanical and antimicrobial properties of the polymer blends and printed material are also assessed. The microstructure of the 3D printed polymer materials is further characterized via DOSY NMR spectroscopy. This study indicates that this is a promising approach for preparing nonleaching antimicrobial 3D printable materials.

In this study, modified nano zinc oxide (ZnO)-reinforced polymer-supported novel thermally enhanced form-stable composite phase change materials (PCMs) are presented, which are prepared via water in oil emulsion polymerization and following impregnation process steps. First, ZnO nanoparticles are modified with oleic acid (OA) to obtain lipophilic structures for emulsion stability, which are designed to take a role as a heat transfer activator. To ensure the shape stabilization of n-hexadecane used as organic PCM, polymeric support materials are synthesized in the presence of modified ZnO nanoparticles (ZnO@OA). The polymeric frameworks exhibit open porous morphology, and the thermal stability of the support matrix improves with the addition of ZnO nanofiller. In the second step, composite PCMs are prepared by incorporation of n-hexadecane with the solvent-assisted vacuum impregnation method into polymer composites. The 1.0% ZnO@OA incorporated composite PCM has the highest incorporation ratio and exhibits a thermal storage capability (η) of 100%. According to the T-history and thermal conductivity tests, it is observed that the heat conduction rate is enhanced with the addition of ZnO@OA nanofiller. The conclusion is that the obtained ZnO@OA integrated composite PCMs have a remarkable potential for latent heat storage applications requiring low temperature in the range of 5–25 °C.

Structurally defined, protein-grafted nanoparticles are widely used in various biomedical applications, particularly as intelligent nanocarriers for drug delivery. The integration of synthetic polymers with natural proteins such as silk sericin enhances the functionality and stability of these nanocarriers, making them suitable for targeted and controlled drug release. In this context, an optimized grafting procedure for silk sericin is presented, employing a protein macroinitiator and atom transfer radical polymerization (ATRP). This study aims to elucidate the significance of the grafting process in tailoring the structure of sericin through the chemistry of synthetic grafts. The grafting procedure uses block copolymers of N-isopropylacrylamide (NIPAM) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS), such as Poly-(AMPS-block-NIPAM)/Poly-(NIPAM-block-AMPS). The procedure employs both one-step and two-step synthesis methods to produce a well-defined, biofunctionalized sericin. Subsequently, sericin-based nanoparticles are prepared, demonstrating the significance of the optimized procedure. The synthesized products undergo structural analysis using H-NMR, FTIR-ATR, XPS, DLS, and zeta potential measurements. In addition, their thermal behavior is assessed using differential scanning calorimetry. To further investigate the prepared nanoparticles, SEM and DLS analyses are conducted. Through synthesis optimization, position and length of each synthetic block is precisely determined, significantly influencing properties of the grafted products and characteristics of the resulting nanoparticles.

This article reports the coexistence of hardening and softening phenomena when polyurea is submitted to repeated nano-impacts with various impact forces while controlling the strain rate. The manifestation of these phenomena is further elucidated by interrogating ultraviolet irradiated samples under ambient and nitrogen atmospheres, wherein artificial weathering accelerates hardening by reducing the nano-impact depths as a function of exposure duration while increasing the impact load, nano-impact repetitions and strain rate sensitivity favored softening. A 21% and 48% increase in indentation depth are recorded after 100 repetitions at a relatively higher force (10 mN) at a low strain rate and low force (2.5 mN) at a relatively higher rate for pristine and weathered polyurea, respectively. Electron microscopy evidences the induced, progressive damage at the nanoscale based on the agglomeration of hard segments, reduced free volume, and weathering-induced surface embrittlement.