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Topic Review
Li-ion Batteries
With the ever-growing energy storage notably due to the electric vehicle market expansion and stationary applications, one of the challenges of lithium batteries lies in the cost and environmental impacts of their manufacture. The main process employed is the solvent-casting method, based on a slurry casted onto a current collector. The disadvantages of this technique include the use of toxic and costly solvents as well as significant quantity of energy required for solvent evaporation and recycling. A solvent-free manufacturing method would represent significant progress in the development of cost-effective and environmentally friendly lithium-ion and lithium metal batteries.
  • 1.5K
  • 11 Jan 2022
Topic Review
Encapsulation of Bioactive Phytochemicals
Many consumers are switching to a plant-based diet because of their concerns about animal-derived foods on the environment, human health, and animal welfare. There has therefore been great interest in identifying, isolating, and characterizing functional ingredients from botanical sources, especially waste streams from food and agricultural production. 
  • 1.5K
  • 16 Jul 2021
Topic Review
Conducting Silicone-Based Polymers
Conducting polymers (CPs) are unique due to their ease of synthesis, environmental stability, and simple doping/dedoping chemistry. Electrically conductive silicone polymers are the current state-of-the-art for, e.g., optoelectronic materials. 
  • 1.5K
  • 23 Apr 2021
Topic Review
Electrospun PVC Nanofibers
Electrospun PVC Nanofibers means PVC nanofibers manufactured by electrospinning.
  • 1.4K
  • 19 Feb 2021
Topic Review
Covalent and Non-Covalent Interactions in Chitosan-Based Biomaterials
Chitosan (CS) is a natural biopolymer that has gained great interest in many research fields due to its promising biocompatibility, biodegradability, and favorable mechanical properties. Through covalent and non-covalent chemical modifications, CS derivatives can reach optimal properties for the development of smart biomaterials in a wide range of biomedial applications.
  • 1.4K
  • 12 Jan 2022
Topic Review
Polymer Nanocomposites
PE and PVC Polymer nanocomposites used in underground cables have been of great interest to researchers over the past 10 years.
  • 1.4K
  • 31 Dec 2020
Topic Review
Flavonoids as Visible Light Photoinitiators
The design of biosourced and/or bioinspired photoinitiators is an active research field as it offers a unique opportunity to develop photoinitiating systems exhibiting better biocompatibility as well as reduced toxicity. In this field, flavonoids can be found in numerous fruits and vegetables so these structures can be of interest for developing, in the future, polymerization processes, offering a reduced environmental impact but also better biocompatibility of the polymers.
  • 1.4K
  • 29 Dec 2023
Topic Review
Self-Healing Elastomers
It is impossible to describe the recent progress of our society without considering the role of polymers; however, for a broad audience, “polymer” is usually related to environmental pollution. The poor disposal and management of polymeric waste has led to an important environmental crisis, and, within polymers, plastics have attracted bad press despite being easily reprocessable. Nonetheless, there is a group of polymeric materials that is particularly more complex to reprocess, rubbers. These macromolecules are formed by irreversible crosslinked networks that give them their characteristic elastic behavior, but at the same time avoid their reprocessing. Conferring them a self-healing capacity stands out as a decisive approach for overcoming this limitation. By this mean, rubbers would be able to repair or restore their damage automatically, autonomously, or by applying an external stimulus, increasing their lifetime, and making them compatible with the circular economy model.
  • 1.4K
  • 26 May 2022
Topic Review
Ionic Hydrogels
Hydrogels are three-dimensional polymer networks with excellent flexibility. Ionic hydrogels have attracted extensive attention in the development of tactile sensors owing to their unique properties, such as ionic conductivity and mechanical properties. These features enable ionic hydrogel-based tactile sensors with exceptional performance in detecting human body movement and identifying external stimuli. Currently, there is a pressing demand for the development of self-powered tactile sensors that integrate ionic conductors and portable power sources into a single device for practical applications.
  • 1.4K
  • 06 Apr 2023
Topic Review
Membrane Fabrication Using Recycled Waste
Polymeric membranes are generally manufactured using a variety of monomers/polymers, including polystyrene, polysulfone (PSF), polyether sulfone (PES), polyaniline, polyvinylidene fluoride (PVDF), and others. The industrial manufacturing of these chemical compounds causes significant greenhouse gas emissions. In addition, the application of these monomer/polymer compounds in daily necessities has been posing a massive burden for their post-utilization disposal. The emergence of waste and its recycling potential has attracted attention to its application in membrane fabrication. The utilization of recycled waste for fabricating the membranes can help in reducing the environmental impact by 2× amount (i.e., eliminate the use of polymer for membrane fabrication and its associated environmental impact and mitigating the effect of waste on the environment via its utilization), thus helping in maintaining environmental sustainability.
  • 1.4K
  • 19 Feb 2024
Topic Review
Waste Plastics’ Liquefaction into Fuel Fraction
Polymers and plastics are crucial materials in many sectors of our economy, due to their numerous advantages. They also have some disadvantages, among the most important are problems with the recycling and disposal of used plastics. The recovery of waste plastics is increasing every year, but over 27% of plastics are landfilled. The rest is recycled, where, unfortunately, incineration is still the most common management method. From an economic perspective, waste management methods that lead to added-value products are most preferred—as in the case of material and chemical recycling. Since chemical recycling can be used for difficult wastes (poorly selected, contaminated), it seems to be the most effective way of managing these materials. Moreover, as a result this of kind of recycling, it is possible to obtain commercially valuable products, such as fractions for fuel composition and monomers for the reproduction of polymers. 
  • 1.4K
  • 06 Dec 2022
Topic Review
The Assembly of PPTA Nanofibers and the Applications
Poly (p-phenylene terephthalamide) (PPTA) is one kind of lyotropic liquid crystal polymer. Kevlar fibers made from PPTA is widely used in many fields due to the superior mechanical properties resulted from highly oriented macromolecular structure. However, the “infusible and insoluble” characteristic of PPTA gives rise to its poor processability, which limits its scope of application. The strong interactions and orientation characteristic of aromatic amide segments make PPTA attractive in the field of self-assembly. The chemical derivations have proved an effective way to modify the molecular structure of PPTA to improve its solubility and amphiphilicity, which resulted in different liquid crystal behaviors or supramolecular aggregates, but the modification of PPTA is usually complex and difficult. Alternatively, higher order all-PPTA structures have also been realized through the controllable hierarchical self-assembly of PPTA from the polymerization process to the formation of macroscopic products. It briefly introduces the self-assembly methods of PPTA based materials in recent years, and focuses on the polymerization-induced PPTA nanofibers which can be further fabricated into different macroscopic architectures when other self-assembly methods are combined. This monomer-started hierarchical self-assembly strategy evokes the feasible processing of PPTA, and enriches the diversity of product, which is expected to be expanded to other liquid crystal polymers.
  • 1.4K
  • 20 Jul 2022
Topic Review
Polyurea for Blast and Impact Protection
Polyurea has attracted extensive attention from researchers and engineers in the field of blast and impact protection due to its excellent quasi-static mechanical properties and dynamic mechanical properties. Its mechanical properties and energy absorption capacity have been tuned by means of formulation optimization, molecular dynamics (MD) simulation and the addition of reinforcing materials. Owing to the special molecular structure of polyurea, the mechanism of polyurea protection against blasts and impacts is the simultaneous effect of multiple properties. For different substrates and structures, polyurea needs to provide different performance characteristics, including adhesion, hardness, breaking elongation, etc., depending on the characteristics of the load to which it is subjected. 
  • 1.4K
  • 11 Jul 2022
Topic Review
CPNHs for Fuel Cell Application
Carbon materials such as carbon graphitic structures, carbon nanotubes, and graphene nanosheets are extensively used as supports for electrocatalysts in fuel cells. Alternatively, conducting polymers displayed ultrahigh electrical conductivity and high chemical stability havegenerated an intense research interest as catalysts support for polymer electrolyte membrane fuel cells (PEMFCs) as well as microbial fuel cells (MFCs). Moreover, metal or metal oxides catalysts can be immobilized on the pure polymer or the functionalized polymer surface to generate conducting polymer-based nanohybrids (CPNHs) with improved catalytic performance and stability. Metal oxides generally have large surface area and/or porous structures and showed unique synergistic effects with CPs. Therefore, a stable, environmentally friendly bio/electro-catalyst can be obtained with CPNHs along with better catalytic activity and enhanced electron-transfer rate.
  • 1.4K
  • 17 Feb 2021
Topic Review
Fully Implanted Hearing Systems
The ear and brain work together in the hearing process. Sound energy in the audible frequency range (20 Hz–20 kHz) propagates through air medium as an acoustical mechanical wave which enters from the outer ear towards the middle ear to vibrate the eardrum. 
  • 1.4K
  • 02 Aug 2021
Topic Review
Preparation of Organosiloxane Telechelics by Cationic Ring-Opening Polymerization
Polydimethylsiloxanes (PDMS) telechelics are important both in industry and in academic research. They are used both in the free state and as part of copolymers and cross-linked materials. The most important, practically used, and well-studied method for the preparation of such PDMS is diorganosiloxane ring-opening polymerization (ROP) in the presence of nucleophilic or electrophilic initiators. Cationic ROP is also of interest for the preparation of functional PDMS. The advantage of this process is that it can be carried out at a relatively low temperature, the catalyst can be easily deactivated, and the process can also be used to synthesize polysiloxanes having base-sensitive substituents such as Si–H or Si–(CH2)3–SH.
  • 1.4K
  • 24 Jun 2022
Topic Review
Polysaccharide Sequence Determination
NMR analysis combined with statistical modeling offers a useful approach to investigate the microstructures of biobased polymers. In particular, this approach may be used to study the microstructures of polysaccharides. If the polysaccharides are composed of two or three monosaccharide units, and the NMR spectral features are sensitive to the different sequence placements of these units, then a detailed analysis of a polysaccharide (or its fractions) can be made by NMR with the help of statistical modeling.   
  • 1.4K
  • 12 Mar 2024
Topic Review
Friction Stir Welding of Polymers
Friction Stir Welding (FSW) is one of the welding methods within the category of friction welding, as it uses the friction between the base material and the tool to generate the heat necessary to soften the material of the joint. The FSW process was developed, demonstrated and patented by “The Welding Institute (TWI)” in England for the first time by Thomas et al.. The principle of the conventional process is illustrated in, as well as its main variables.
  • 1.4K
  • 30 Jun 2021
Topic Review
Kappa-2 Carrageenans
Hybrid carrageenans, also called kappa-2 (K2) or weak kappa, are a class of sulfated polysaccharides with thermo-reversible gelling properties in water and are extracted from a specific family of red seaweeds. K2 are known in the industry for their texturizing properties which are intermediate between those of kappa-carrageenans (K) and iota-carrageenans (I). As such, K2 are gaining industrial interest, as they can replace blends of K and I (K + I) in some niche applications. 
  • 1.4K
  • 22 Sep 2023
Topic Review
Perfluoropyridine
The fluorine atom exhibits many unique properties, including a small atomic radius, large electronegativity, and minimal polarizability. Thus, when coupled with carbon in the form of a C-F bond, organofluorine compounds with highly sought after properties can be obtained. Perfluoropyridine (PFPy) is an organofluorine compound that has been employed for a variety of applications, from straightforward chemical synthesis to more advanced functions, such as fluorinated networks and polymers. This can be directly attributed to the highly reactive nature of PFPy, especially towards nucleophilic aromatic substitution (SNAr).
  • 1.4K
  • 10 Mar 2022
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