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Topic Review
Synthesis of Polymers for Electrospun Nanofiber Membranes
The use of nanofiber a filtering medium is well established, and the electrospun nanofiber have several applications such as electrospun fibers for air purification and air filtration media. The different characteristics of nanofibers as morphologies, mechanical and optical properties, thermal stability, electrical conductivity, photocatalytic activity and bioactivity underlie their macromolecular structure and chemical composition. 
  • 1.0K
  • 08 Feb 2023
Topic Review
Bioactive Polymers via the Biginelli Reaction
Multicomponent reactions (MCRs) have been used to prepare polymers with appealing functions. The Biginelli reaction, one of the oldest and most famous MCRs, has sparked new scientific discoveries in polymer chemistry since 2013. The applications of the Biginelli reaction in developing functional polymers are mainly focusing on polymers that can be used in the biomedical area as antioxidants, anticancer agents, and bioimaging probes.
  • 1.0K
  • 22 Nov 2022
Topic Review
Aerogels for the Removal of Heavy Metal Ions
Aerogel is a general term referring to novel nanostructured materials characterized by very high porosity and tunable physicochemical properties that are obtained following a sol–gel process and an appropriate drying method. Such novel materials are entering the market in everyday products and a wide portfolio of properties usable for applications in health care, foods, agriculture, energy, and environmental remediation. Bio-based aerogels obtained from renewable resources and biomass are biodegradable and biocompatible due to the natural origin of the polymers, and for this reason, they greatly contribute to the sustainable concept of the bio-economy, offering promising commodities for environmental remediation.
  • 1.0K
  • 22 Jan 2024
Topic Review
Solid State Nuclear Magnetic Resonance Investigating Cellulose-Based Materials
Solid state nuclear magnetic resonance (ssNMR) is a powerful and attractive characterization method for obtaining insights into the chemical structure and dynamics of a wide range of materials. Current interest in cellulose-based materials, as sustainable and renewable natural polymer products, requires deep investigation and analysis of the chemical structure, molecular packing, end chain motion, functional modification, and solvent–matrix interactions, which strongly dictate the final product properties and tailor their end applications. In comparison to other spectroscopic techniques, on an atomic level, ssNMR is considered more advanced, especially in the structural analysis of cellulose-based materials
  • 1.0K
  • 15 Apr 2022
Topic Review
PEDOT-based Catalytic Counter Electrode Material
Dye-sensitized solar cells (DSSCs) emerged in the early 1990s as a promising alternative to the classic silicon-based solar cell due to their unique combination of low cost, ease of fabrication, color palette for building integration, and high efficiency in indoor applications. 
  • 1.0K
  • 08 May 2021
Topic Review
Simultaneous Production of Cellulose Nitrates and Bacterial Cellulose
The scientific hypothesis about the possibility of simultaneous production of two independent of each other products from Miscanthus giganteus, namely the product of chemical modification of cellulose - cellulose nitrates and the product of biosynthesis - bacterial cellulose was tested.
  • 1.0K
  • 27 Dec 2023
Topic Review
Directed Assembly of Particle-Polymer Composites
Particle-polymer dispersions are ubiquitous in additive manufacturing (AM), where they are used as inks to create composite materials with applications to wearable sensors, energy storage materials, and actuation elements. It has been observed that directional alignment of the particle phase in the polymer dispersion can imbue the resulting composite material with enhanced mechanical, electrical, thermal or optical properties. 
  • 1.0K
  • 17 Aug 2021
Topic Review
Natural Polymer-Based Hydrogels for Glaucoma Therapy
Biopolymers have been extensively investigated in a number of medical fields, including tissue engineering and drug delivery. This is largely due to the fact that they are biodegradable within the body, and do not induce an inflammatory reaction. Polynucleotides such as nucleic acids (DNA and RNA), proteins such as polypeptides, and polyesters derived from both plants and animals are also used. When compared to synthetic polymers, naturally occurring biopolymers and their derivatives have acquired preference, and have a comprehensive range of applications in pharmaceutical as well as biomedical research. Natural biopolymers are preferred for medical applications due to their biodegradability, biostability, biocompatibility, and non-toxicity. Additionally, natural polymers have the advantage of being readily available, economically friendly, and ecofriendly. Hydrogels designed from natural polymers exhibit high potential as drug delivery systems for biomaterials to treat ocular impairments.
  • 1.0K
  • 28 Jun 2022
Topic Review
Biocomposite Based on Natural Polymers
Biopolymers are materials obtained from renewable resources. Despite the exciting properties of biopolymers, such as biocompatibility and environmental sustainability, they do not present antimicrobial properties (except chitosan). However, this lack of antimicrobial properties can be solved by incorporating or encapsulating antimicrobial agents. Natural polymers possess low stability in aqueous media and limited mechanical strength, which could be improved through cross-linking strategies. Hydrogels are biocompatible materials that can be synthesized from natural polymers, forming a cross-linking material. Alginate, collagen, fibrin, chitosan, gelatin, and hyaluronic acid are some natural polymers used to synthesize hydrogels.
  • 1.0K
  • 12 Jul 2022
Topic Review
Crosslinked nanogel for cancer theranostics
Crosslinked nanogels the structures of which are covalently crosslinked have better physiological stability than micelles and liposomes, making them more suitable for cancer theranostics. The applications of nanogels in drug and gene delivery as well as development of novel cancer therapeutic methods are first introduced, followed by the introduction of applications in optical and multimodal imaging, and imaging-guided cancer therapy. 
  • 999
  • 01 Sep 2020
Topic Review
Weak Polyelectrolytes for Nanoarchitectonic Design Tools
The ionization degree, charge density, and conformation of weak polyelectrolytes can be adjusted through adjusting the pH and ionic strength stimuli. Such polymers thus offer a range of reversible interactions, including electrostatic complexation, H-bonding, and hydrophobic interactions, which position weak polyelectrolytes as key nano-units for the design of dynamic systems with precise structures, compositions, and responses to stimuli. From surface platforms to colloids and gels, weak polyelectrolytes have enabled the development of a wide range of functional materials owing to their intrinsic response to stimuli, including solvents, temperature, pH, and salt.
  • 997
  • 30 May 2022
Topic Review
Aliphatic Polyesters by ADMET Polymerization and Hydrogenation
The recent developments of the synthesis of bio-based long-chain aliphatic polyesters by the acyclic diene metathesis (ADMET) polymerization of α,ω-dienes, derived from plant oils and bio-based chemicals, like bis(10-undecenoate) with isosorbide, using ruthenium-carbene catalysts. The development of subsequent (one-pot) tandem hydrogenation produced saturated polyesters under mild conditions.
  • 995
  • 06 Feb 2024
Topic Review
Mucoadhesive and Mucopenetrating Polymer-Based Adjuvants
Mucus is a viscoelastic gel that acts as a protective barrier for epithelial surfaces. The mucosal vehicles and adjuvants need to pass through the mucus layer to make drugs and vaccine delivery by mucosal routes possible. The mucoadhesion of polymer particle adjuvants significantly increases the contact time between vaccine formulations and the mucosa; then, the particles can penetrate the mucus layer and epithelium to reach mucosa-associated lymphoid tissues.
  • 993
  • 23 May 2023
Topic Review
Polymer Membranes in Contamination Situations
Depending on the type of contamination, various methods are used, including sorption, biodegradation, separation, or ion exchange processes in which membranes play an important role. The type of membrane is selected in respect of both the environment and the type of neutralized pollutants.
  • 992
  • 17 Jun 2021
Topic Review
Glass–fibre–reinforced Polymer
Wind barrier structures are usually installed on railway bridges to reduce wind effects on travelling trains for safety considerations. This however adversely transfers wind loads and causes associated aerodynamic effects to the bridge. An innovative concept of wind barriers using glass fibre reinforced polymer (GFRP) composites is proposed in this work with experimental investigations and numerical modelling. This work provides a solution to mitigate the wind and associated aerodynamic loads. With an appropriate design of bending stiffness, the proposed barriers may deform adaptively in strong wind scenarios and let the wind to pass through their deformed shape and therefore transfer less load to the bridge. Wind-tunnel experiments and numerical studies are conducted on the aerodynamic responses of the train-barrier-bridge system under crosswind with various speeds. The influences of barrier height, air-flow speed and location of the train on the aerodynamic responses of the system were clarified. Both reduced-scale and full-scale finite element models were established for the train-barrier-bridge system and the results were validated with the experimental results to further support the research findings.
  • 991
  • 22 Oct 2020
Topic Review
Covalent Organic for Solar Fuel
Harnessing solar energy and converting it into renewable fuels by chemical processes, such as water splitting and carbon dioxide (CO2) reduction, is a highly promising yet challenging strategy to mitigate the effects arising from the global energy crisis and serious environmental concerns. In recent years, covalent organic framework (COF)-based materials have gained substantial research interest because of their diversified architecture, tunable composition, large surface area, and high thermal and chemical stability. Their tunable band structure and significant light absorption with higher charge separation efficiency of photoinduced carriers make them suitable candidates for photocatalytic applications in hydrogen (H2) generation, CO2 conversion, and various organic transformation reactions. 
  • 991
  • 13 Jul 2021
Topic Review
Crosslinking Density in Imprinting Polymerization
The crosslinking density of a material determines its physical properties, such as the porosity of the material. In imprinting polymerizations, the porosity determines access to internal binding sites and thus the capacity of the imprinted material. This entry is about effect of the commonly used crosslinking density in imprinting polymerization for a variety of applications.
  • 991
  • 30 Sep 2021
Topic Review
Chemical Recycling for Plastic Waste
Plastics play an integral role in shaping our modern society and are ubiquitous in our daily lives. Their superior material characteristics, performance, and low production cost make them desirable for vast consumer and industrial applications. Chemical or feedstock recycling refers to any reprocessing technology directly affecting the formulation of polymeric waste or the polymer itself.  The recycling plastic waste through chemical means are explored.
  • 982
  • 23 May 2023
Topic Review
Organic Photorefractive Materials
Photorefractive materials are capable of reversibly changing their index of refraction upon illumination. That property allows them to dynamically record holograms, which is a key function for developing an updateable holographic 3D display. The transition from inorganic photorefractive crystals to organic polymers meant that large display screens could be made.
  • 972
  • 01 Dec 2021
Topic Review
Solid-State Zinc Secondary Batteries with Alkaline Electrolytes
Aqueous zinc-ion batteries (ZIBs) have gained significant recognition as highly promising rechargeable batteries for the future due to their exceptional safety, low operating costs, and environmental advantages. Alkaline electrolytes have a long history of application in zinc-ion batteries. Alkaline electrolytes offer several advantages compared to neutral and acidic electrolytes. The benefits of alkaline electrolytes encompass a high operating voltage, rapid reaction kinetics, and enhanced ionic conductivity. KOH is the preferred alkaline electrolyte in rechargeable zinc batteries due to its notable characteristics such as the high solubility of zinc salt in KOH solution and the superior ionic conductivity of K+ (73.5 S cm−2) compared to Na+ (50.1 S cm−2) and Li+ (38.7 S cm−2). 
  • 972
  • 17 Oct 2023
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