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Electrospun polymer nanofibers (EPNF) constitute one of the most important nanomaterials with diverse applications. An overall review of EPNF is presented here, starting with an introduction to the most attractive features of these materials, which include the high aspect ratio and area to volume ratio as well as excellent processability through various production techniques. A review of these techniques is featured with a focus on electrospinning, which is the most widely used, with a detailed description and different types of the process. Polymers used in electrospinning are also reviewed with the solvent effect highlighted, followed by a discussion of the parameters of the electrospinning process. The mechanical properties of EPNF are discussed in detail with a focus on tests and techniques used for determining them, followed by a section for other properties including electrical, chemical, and optical properties. The final section is dedicated to the most important applications for EPNF, which constitute the driver for the relentless pursuit of their continuous development and improvement. These applications include biomedical application such as tissue engineering, wound healing and dressing, and drug delivery systems. In addition, sensors and biosensors applications, air filtration, defense applications, and energy devices are reviewed. A brief conclusion is presented at the end with the most important findings and directions for future research.

This literature review covers the solubility and processability of fluoropolymer polyvinylidine fluoride (PVDF). Fluoropolymers consist of a carbon backbone chain with multiple connected C–F bonds; they are typically nonreactive and nontoxic and have good thermal stability. Their processing, recycling and reuse are rapidly becoming more important to the circular economy as fluoropolymers find widespread application in diverse sectors including construction, automotive engineering and electronics. The partially fluorinated polymer PVDF is in strong demand in all of these areas; in addition to its desirable inertness, which is typical of most fluoropolymers, it also has a high dielectric constant and can be ferroelectric in some of its crystal phases. However, processing and reusing PVDF is a challenging task, and this is partly due to its limited solubility. This review begins with a discussion on the useful properties and applications of PVDF, followed by a discussion on the known solvents and diluents of PVDF and how it can be formed into membranes. Finally, we explore the limitations of PVDF’s chemical and thermal stability, with a discussion on conditions under which it can degrade. Our aim is to provide a condensed overview that will be of use to both chemists and engineers who need to work with PVDF.

In this work, the numerical simulation of the non-isothermal steady co-extrusion fiber spinning with flow-induced crystallization is explored. The model is based on the formulation originally proposed by China et al. in which Newtonian and Phan-Thien-Tanner (PTT) fluids are considered the core and the skin layer, respectively. The polymeric flow rate fraction, Deborah dimensionless number and the PTTs parameters on the temperature, the velocity and the crystallization profiles are analyzed. The numerical results show: the temperature profile is sensitive to the polymeric layer flow rate and the deformation parameters (shear thinning and extensional), the tensile stress induced crystallization parameter has a strong influence at the onset of the process, increasing drastically temperature and crystallinity.

The aim of this review is a faithful report of the panorama of solutions adopted to fabricate a component using vat photopolymerization (VP) processes. A general overview on additive manufacturing and on the different technologies available for polymers is given. A comparison between stereolithography and digital light processing is also presented, with attention to different aspects and to the advantages and limitations of both technologies. Afterward, a quick overview of the process parameters is given, with an emphasis on the necessities and the issues associated with the VP process. The materials are then explored, starting from base matrix materials to composites and nanocomposites, with attention to examples of applications and explanations of the main factors involved.

The present study deals with the swimming of gyrotactic microorganisms in a nanofluid past a stretched surface. The combined effects of magnetohydrodynamics and porosity are taken into account. The mathematical modeling is based on momentum, energy, nanoparticle concentration, and microorganisms’ equation. A new computational technique, namely successive local linearization method (SLLM), is used to solve nonlinear coupled differential equations. The SLLM algorithm is smooth to establish and employ because this method is based on a simple univariate linearization of nonlinear functions. The numerical efficiency of SLLM is much powerful as it develops a series of equations which can be subsequently solved by reutilizing the data from the solution of one equation in the next one. The convergence was improved through relaxation parameters in the study. The accuracy of SLLM was assured through known methods and convergence analysis. A comparison of the proposed method with the existing literature has also been made and found an excellent agreement. It is worth mentioning that the successive local linearization method was found to be very stable and flexible for resolving the issues of nonlinear magnetic materials processing transport phenomena.

Whilst synthetic polymers have changed the world in many important ways, the negative impacts associated with these materials are becoming apparent in waste accumulation and microplastic pollution due to lack of biodegradability. Society has become aware of the need to replace or substitute environmentally persistent synthetic polymers, and cellulose has received a large amount of attention in this respect. The mechanical properties of cellulose, its renewable nature and biodegradability are advantageous properties. Drawbacks exist for the use of plant cellulose (PC), including the water footprint of cotton, deforestation associated with wood/dissolving pulp, and the extensive processing required to refine plants and wood into pure cellulose. Bacterial cellulose (BC), also known as microbial cellulose, is gaining momentum in both academic and industry settings as a potential solution to the many drawbacks of plant-based cellulose. Compared to PC, BC has high purity, crystallinity and degree of polymerisation, and can be manufactured from waste in a way that yields more cellulose per hectare, per annum, and requires less intense chemical processing. Native bacterial cellulose can be formed and shaped to an extent and is found in a variety of commercial products. However, dissolving and regenerating bacterial cellulose is a potential avenue to broaden the applications available to this material. The aim of this study is to review the applications which utilize regenerated bacterial cellulose, with a focus on the dissolution/regeneration methods used and discussing the associated limitations and future outlook.

Layer multiplying co‐extrusion (LMCE) is a versatile and scalable technology for manufacturing polymeric composites with micro‐ and nano‐scale templated features. While previous studies have primarily focused on applications with neat polymers, incorporation of solid fillers into layered structures at high loading levels would enable new types of polymeric composites and templated precursors to dense solids. In this initial study, processing conditions and limitations of the LMCE process with respect to highly filled systems are explored using a model system of glass microsphere fillers in a polyolefin binder. Scanning electron microscopy of film cross‐sections indicates that layering persists for viscosity‐matched systems even as layer thicknesses approach the characteristic particle size of the fillers. However, when there is a significant viscosity mismatch between the filled and unfilled layers, an interfacial instability arises which disrupts the layer structure in high shear regions. These results demonstrate the feasibility of LMCE for highly filled systems and point to processing guidelines for the stable production of filled microlayer structures. This study explores processing conditions during the co‐extrusion of highly particle‐filled layered polymeric composites. With an appropriate rheology match, layers with thicknesses approaching the particle sizes are possible. However, instability‐driven layer break‐up occurs when a critical interfacial shear stress is exceeded.

By integrating multi-scale computational simulation with photo-regulated macromolecular synthesis, this study presents a new paradigm for smart design while customizing polymeric adsorbents for uranium harvesting from seawater. A dissipative particle dynamics (DPD) approach, combined with a molecular dynamics (MD) study, is performed to simulate the conformational dynamics and adsorption process of a model uranium grabber, i.e., PAO m - b -PPEGMA n , suggesting that the maximum adsorption capacity with atomic economy can be achieved with a preferred block ratio of 0.18. The designed polymers are synthesized using the PET-RAFT polymerization in a microfluidic platform, exhibiting a record high adsorption capacity of uranium (11.4 ± 1.2 mg/g) in real seawater within 28 days. This study offers an integrated perspective to quantitatively assess adsorption phenomena of polymers, bridging metal-ligand interactions at the molecular level with their spatial conformations at the mesoscopic level. The established protocol is generally adaptable for target-oriented development of more advanced polymers for broadened applications. Developing materials for uranium harvesting from seawater with high adsorption capacity remains challenging. Here, the authors develop a new protocol, by combining multi-scale computational simulations with the PET-RAFT polymerization, for rational design and precise synthesis of block copolymers with optimal architectures and atomic economy, achieving a capacity of 11.4 mg/g within 28 days.

Poly(lactic acid) (PLA) brings intriguing prospects to the realm of biodegradable polymers through environmental sustainability, processing, and affordability. However, the widespread use of PLA remains full of challenges mostly because of its brittleness and poor mechanical properties. This review highlighted recent studies on improving PLA brittleness by adding different elastomeric systems and using different crosslinking systems in order to improve the mechanical properties, enhance the interfacial interactions, and stabilize the micromorphology of PLA systems as an effective, promising strategy to mitigate intrinsic PLA problems. Looking at the different microstructures required to achieve better performance, an insightful discussion on the developed morphology between PLA and high‐elastic materials is featured along with reviewing primary mechanical concepts. It concludes with an outlook for static and dynamic vulcanization systems with a perspective of biodegradable PLA and draws attention to the new possibilities that crosslinked PLA can offer. This review highlights PLA‐based Thermoplastic Vulcanizates (TPVs) as promising materials that combine the processability of thermoplastics and elastomeric properties. Dynamic vulcanization of PLA‐based thermoplastic elastomers leads to new morphology such as sea‐sea or honeycomb structures. Optimizing rubber and vulcanization can yield super‐tough TPVs. Despite challenges in processing, PLA‐based TPVs show strong potential for diverse applications as sustainable alternatives.

Biopolymer-based aerogels can be obtained by supercritical drying of wet gels and endowed with outstanding properties for biomedical applications. Namely, polysaccharide-based aerogels in the form of microparticles are of special interest for wound treatment and can also be loaded with bioactive agents to improve the healing process. However, the production of the precursor gel may be limited by the viscosity of the polysaccharide initial solution. The jet cutting technique is regarded as a suitable processing technique to overcome this problem. In this work, the technological combination of jet cutting and supercritical drying of gels was assessed to produce chitosan aerogel microparticles loaded with vancomycin HCl (antimicrobial agent) for wound healing purposes. The resulting aerogel formulation was evaluated in terms of morphology, textural properties, drug loading, and release profile. Aerogels were also tested for wound application in terms of exudate sorption capacity, antimicrobial activity, hemocompatibility, and cytocompatibility. Overall, the microparticles had excellent textural properties, absorbed high amounts of exudate, and controlled the release of vancomycin HCl, providing sustained antimicrobial activity.