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Antimicrobial polymers represent a very promising class of therapeutics with unique characteristics for fighting microbial infections. As the classic antibiotics exhibit an increasingly low capacity to effectively act on microorganisms, new solutions must be developed. The importance of this class of materials emerged from the uncontrolled use of antibiotics, which led to the advent of multidrug-resistant microbes, being nowadays one of the most serious public health problems. This review presents a critical discussion of the latest developments involving the use of different classes of antimicrobial polymers. The synthesis pathways used to afford macromolecules with antimicrobial properties, as well as the relationship between the structure and performance of these materials are discussed.

Adhesives and sealants (AS) are materials with excellent properties, versatility, and simple curing mechanisms, being widely used in different areas ranging from the construction to the medical sectors. Due to the fast-growing demand for petroleum-based products and the consequent negative environmental impact, there is an increasing need to develop novel and more sustainable sources to obtain raw materials (monomers). This reality is particularly relevant for AS industries, which are generally dependent on non-sustainable fossil raw materials. In this respect, biopolymers, such as cellulose, starch, lignin, or proteins, emerge as important alternatives. Nevertheless, substantial improvements and developments are still required in order to simplify the synthetic routes, as well as to improve the biopolymer stability and performance of these new bio-based AS formulations. This environmentally friendly strategy will hopefully lead to the future partial or even total replacement of non-renewable petroleum-based feedstock. In this brief overview, the general features of typical AS are reviewed and critically discussed regarding their drawbacks and advantages. Moreover, the challenges faced by novel and more ecological alternatives, in particular lignocellulose-based solutions, are highlighted.

The gamification of education can enhance levels of students’ engagement similar to what games can do, to improve their particular skills and optimize their learning. On the other hand, scientific studies have shown adverse outcomes based on the user’s preferences. The link among the user’s characteristics, executed actions, and the game elements is still an open question. Aiming to find some insights for this issue, we have investigated the effects of gamification on students’ learning, behavior, and engagement based on their personality traits in a web-based programming learning environment. We have conducted an experiment for four months with 40 undergraduate students of first-year courses on programming. Students were randomly assigned to one of the two versions of the programming learning environment: a gamified version composed of ranking, points, and badges and the original non-gamified version. We have found evidence that gamification affected users in distinct ways based on their personality traits. Our results indicate that the effect of gamification depends on the specific characteristics of users. First part title: Studying the impact of gamification on learning and engagement based on the personality traits of students

The concern for the environment and sustainability has intensified the search for alternative materials to replace non-degradable plastics. Poly(butylene adipate-co-terephthalate) (PBAT) is a bioplastic that has been extensively studied due to its excellent mechanical properties, which are similar to those of low-density poly(ethylene) (LDPE). However, the high cost of this polymer still hinders its wider application. Among the different approaches that have been studied, blending PBAT with thermoplastic starch (TPS) could be an interesting solution to reduce the cost of the material and increase the degradability of the blends. This review covers most of the work reported in recent years on PBAT/TPS blends, including the effects of starch plasticizers, starch modifications, processing methods, use of chain extenders, various compatibilizers, and additives used for different applications.

Flexible, monolithic and superhydrophobic silica aerogels were obtained by combining methyltrimethoxysilane (MTMS), vinyltrimethoxysilane (VTMS) and tetramethylorthosilicate (TMOS) (50:30:20 mol%) in a one-step base-catalyzed co-precursor sol–gel procedure. Polybutylacrylate (PBA) and polystyrene (PS) were grafted and cross-linked in the gel aiming to enhance the mechanical performance. Fourier transform infrared spectroscopy, thermogravimetry analysis and scanning electron microscopy confirmed the presence of the polymers as a binding coating on the 3D silica network, primarily formed by firmly connected 3–5 μm secondary particles. When compared to the MTMS-based aerogels, the VTMS–MTMS–TMOS-derived aerogels, either reinforced or not, show a threefold increase of the bulk density (to ~150–160 kg m⁻³) and a consequent decrease in the surface area and average pore size; the thermal conductivity also increases to 60–70 mW m⁻¹ K⁻¹, a 50 % increase over the values of MTMS-derived aerogels. Although these tendencies are more marked in the polymer-reinforced materials, the change of the silica skeleton from MTMS to VTMS–MTMS–TMOS is responsible for the main differences. The VTMS–MTMS–TMOS underlying structure gives a fourfold increase in compressive strength relatively to the MTMS-derived aerogels, even when not reinforced. In addition, it retains a high elongation at break (40–50 %) and flexibility—modulus of 25 kPa for the PBA-reinforced aerogel, the more flexible aerogel, and modulus of 91 kPa for PS-reinforced aerogel, the stiffer and stronger material. The obtained aerogels have touch feeling that resembles that of expanded polystyrene foams, and also show negligible particle shedding, which is a valued characteristic for aerospace applications.

This concept focuses on the application of alternating current (AC) and pulsed electrolysis in Atom Transfer Radical Polymerization (ATRP) for polymer synthesis. AC electrolysis, which oscillates between reduction and oxidation, can be tuned to increase selectivity for a specific reaction pathway, minimize side reactions, and improve product selectivity and reagent conversion. Pulsed electrolysis can also be used to sustain electrochemical reactions in ATRP. The challenges and limitations associated with AC electrolysis are discussed along with an outlook on future developments in polymer synthesis and related applications. A concise overview of recent developments in electro‐organic synthesis using AC electrolysis will be provided. AC electrolysis is emerging as a promising method for electrifying chemical synthesis, offering potential benefits, such as improved reaction control and sustainability in ATRP. However, optimizing AC electrolysis parameters, such as frequency and waveform, remains complex. High‐throughput methods and machine learning can be used to accelerate this process. Expanding AC capabilities in electrochemical instrumentation, especially for polymerization processes such as eATRP, could transform large‐scale polymer production and other electrosynthetic applications.

The lack of personalized wound dressings tailored to individual needs can significantly hinder wound healing. Hydrogels offer a promising solution, as they can be engineered to mimic the extracellular matrix (ECM), providing an optimal environment for wound repair. The integration of digital light processing (DLP), a high-resolution 3D printing process, allows precise customization of hydrogel-based wound dressings. In this study, gelatin methacrylate (GelMA)-based formulations were prepared in combination with three different polymeric precursors: methacrylated hyaluronic acid (HAMA), poly (ethylene glycol) diacrylate (PEGDA) and allyl cellulose (MCCA). These precursors were used to print high-resolution micropatterned patches. The printed constructs revealed a high gel content and a good resistance to hydrolytic degradation. To improve the adhesive and antioxidant properties of the printed patches, gallic acid (GA) was incorporated through surface functionalization. This enabled the scavenging of approximately 80% of free radicals within just 4 h. The adhesive properties of the printed wound dressings were also significantly improved, with further enhancement observed upon the addition of Fe3+ ions. In vitro cytocompatibility tests using a fibroblast (NHDF) cell line confirmed the suitability of the materials for biomedical applications. Thus, this study demonstrates the potential of DLP-printed hydrogels as advanced personalized wound dressing materials.

Polymers generally form incompatible mixtures that make the process of recycling difficult, especially the mechanical recycling of mixed plastic waste. One of the most commonly used films in the packaging industry is multilayer films, mainly composed of polyethylene (PE) and polyamide (PA). Recycling these materials with such different molecular structures requires the use of compatibilizers to minimize phase separation and obtain more useful recycled materials. In this work, commercial polyisoprene–graft–maleic anhydride (PI-g-MA) was tested as a compatibilizer for a blend of PE and PA derived from the mechanical recycling of PE/PA multilayer films. Different amounts of PI-g-MA were tested, and the films made with 1.5% PI-g-MA showed the best results in terms of mechanical properties and dart impact. The films were also characterized thermally via thermogravimetric analysis (TG) and differential scanning calorimetry (DSC), using Fourier-transform infrared spectroscopy (FTIR), and morphologically using a scanning electron microscope (SEM). Other parameters, such as tearing and perforation, were analyzed.

In this paper, we present a framework for exploring the spare capacity of IoT devices for clustered execution of multimedia applications. Applications of this type are usually framed with specific quality parameters that enable a desirable level of service. This means that the IoT cluster must guarantee strict quality ranges of service to work as expected. The framework is totally customizable, and QoS dimensions can be easily added or removed given their relevance in the application scenario. The achieved results clearly demonstrate the utility of using the spare capacity of IoT devices, otherwise unused, to cooperatively execute servies within the desired quality of service levels.

Non-biodegradable superabsorbent polymers (SAPs) in personal care products (PCPs) pose significant environmental and health concerns despite their high absorption capacity. The aim of this study was to develop cellulose-based hydrogels as a sustainable alternative to those conventional SAPs, taking advantage of cellulose properties such as biocompatibility, biodegradability, and hydrophilicity. A synthesized allyl cellulose (AC) derivative was copolymerized with unusual monomers used in the production of SAPs, and the influence of monomer ratios, crosslinking density, and the ratio of cellulose to monomers on the absorption capacity was investigated and optimized. The most promising hydrogels were fully characterized for the proposed application and compared with a commercial SAP extracted from a baby diaper. The cellulose-based hydrogels showed promising absorption capacities in synthetic urine (~15 g/g), and a high centrifuge retention capacity (12.5 g/g), which was only slightly lower than the commercial SAP. These new hydrogels exhibited excellent biocompatibility and outperformed the established commercial diaper SAP. This study represents a more sustainable alternative to conventional SAPs, potentially reducing health risks while increasing the bio-based content of PCPs. Further optimization of these hydrogels could transform the hygiene product industry, by providing a balance between performance and environmental sustainability.