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Topic Review
Material Reactions, Degradation and Applications of Polyvinylidene Fluoride
Polyvinylidene fluoride (PVDF), the chemical formula is (C2H2F2)n. Its basic building blocks are therefore carbon, hydrogen, and fluorine. These three elements can form several crystalline chain conformations. Conformations are defined by polar and nonpolar phases. Four phases are most commonly found in the literature: α-, β-, γ-, and δ-. 
  • 651
  • 17 Oct 2022
Topic Review
Carbon Nanomaterials for Electro-Active Structures
The use of electrically conductive materials to impart electrical properties to substrates for cell attachment, proliferation and differentiation, represents an important strategy in the field of tissue engineering. Carbon nanomaterials have great potential for fabricating electro-active structures due to their exceptional electrical and surface properties, opening new routes for more efficient tissue engineering approaches. The concept of electro-active structures and their roles in tissue engineering is discussed in this review, the most relevant carbon-based nanomaterials used to produce electro-active structures are presented. Particular emphasis is put on the electrically conductive property, material synthesis and their applications on tissue engineering. Different technologies, allowing the fabrication of two-dimensional and three-dimensional structures in a controlled way, are also presented. Finally, challenges for future research are highlighted. 
  • 645
  • 18 Dec 2020
Topic Review
Soluble Chitosan Derivatives Nanoparticles
Herein, a novel chitosan derivative nanoparticle was proposed to function as a delivery carrier. First of all, an improvement was made to the way N-2-hydroxypropyl trimcthyl ammonium chloride chitosan (N-2-HACC) was synthesized. 
  • 643
  • 02 Dec 2021
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.
  • 640
  • 17 Jun 2021
Topic Review
Recycling of High-Molecular-Weight Organosilicon Compounds in Supercritical Fluids
The main known patterns of thermal and/or catalytic destruction of high-molecular-weight organosilicon compounds are considered from the viewpoint of the prospects for processing their wastes. The advantages of using supercritical fluids in plastic recycling are outlined in this entry. They are related to a high diffusion rate, efficient extraction of degradation products, the dependence of solvent properties on pressure and temperature, etc. A promising area for further research is described concerning the application of supercritical fluids for processing the wastes of organosilicon macromolecular compounds.
  • 640
  • 14 Dec 2022
Topic Review
Effect of Nano-Additives on PLA/Nanocomposite Properties
Poly(lactic acid) (PLA) is considered the most promising biobased substitute for fossil-derived polymers due to its compostability, biocompatibility, renewability, and good thermomechanical properties. However, PLA suffers from several shortcomings, such as low heat distortion temperature, thermal resistance, and rate of crystallization, whereas some other specific properties, i.e., flame retardancy, anti-UV, antibacterial or barrier properties, antistatic to conductive electrical characteristics, etc., are required by different end-use sectors. The addition of different nanofillers represents an attractive way to develop and enhance the properties of neat PLA. Numerous nanofillers with different architectures and properties have been investigated, with satisfactory achievements, in the design of PLA nanocomposites.
  • 640
  • 21 Mar 2023
Topic Review
Quinoxaline-Based Photoinitiators of Polymerization
Photopolymerization offers a unique opportunity to convert liquid monomers to polymers using light as the activation source. Major efforts have been devoted to developing visible light photo-initiating systems, and the search for new dyes that can be incorporated into photocurable resins and polymerize a resin within a few seconds is still ongoing.
  • 640
  • 24 Apr 2023
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. 
  • 636
  • 08 May 2021
Topic Review
Improving the Barrier Properties of the Biodegradable Polymers
Biodegradable polymers have become a topic of great scientific and industrial interest due to their environmentally friendly nature. For the benefit of the market economy and environment, biodegradable materials should play a more critical role in packaging materials. 
  • 636
  • 27 Feb 2024
Topic Review
General Synthesis Methods of Poly (ε-caprolactone)-Based Graft Copolymers
Synthetic biopolymers are attractive alternatives to biobased polymers, especially because they rarely induce an immune response in a living organism. Poly ε-caprolactone (PCL) is a well-known synthetic aliphatic polyester universally used for many applications, including biomedical and environmental ones.  To expand the range of applications for PCL, researchers have investigated the possibility of grafting polymer chains onto the PCL backbone. As the PCL backbone is not functionalized, it must be first functionalized in order to be able to graft reactive groups onto the PCL chain. These reactive groups will then allow the grafting of new reagents and especially new polymer chains. Grafting of polymer chains is mainly carried out by “grafting from” or “grafting onto” methods.
  • 633
  • 29 Nov 2022
Topic Review
Silicones Renewed for Emerging Applications
Polydimethylsiloxane (PDMS) is the basis of the vast majority of silicone products that have found use in almost all areas of human activity, from cosmetics to the nuclear or aerospace industry. After 80 years from the first direct synthesis of silicones (2020), they still enjoy great interest, both scientific and applicative, being extremely versatile. Polydimethylsiloxane (PDMS), in spite of its well-defined helical structure, is an amorphous fluid even at extremely high molecular weights. The cause of this behavior is the high flexibility of the siloxane backbone and the lack of intermolecular interactions attributed to the presence of methyl groups. These make PDMS incompatible with almost any organic or inorganic component leading to phase separation in copolymers and blends. The material itself is hydrophobic and permeable to gases, with low viscosity, solubility parameters, low glass transition temperature and very low surface tension. This makes the silicones spread very easily, distinguished by their ability to form temporary films and thin coatings to more substantial durable films or with self-leveling and adhesive capacities as stand-alone sheets of different sizes and thickness, from a few micrometers to a few millimeters. One application that is based on this property is the formation of free standing, flexible submicrometric films of interest as active elements in certain devices, such as dielectric elastomer transducers (DETs). Dielectric elastomers (DEs), three-dimensional networks of long and flexible polymer chains, are soft active materials showing promising properties that mimic natural muscle for use in advanced robotics and smart prosthetics, as well as in haptic and microfluidic devices. They enjoy great interest due to their inherent flexibility, large strain, high efficiency, high energy density, and fast response of the material. In addition, some of their properties can be adjusted as required by chemical, physical or combined approaches. 
  • 623
  • 23 Jun 2021
Topic Review
Biodegradable Microparticles for Regenerative Medicine
Regenerative medicine is one of the most attractive topics of research worldwide. Different strategies are proposed, and a range of materials of various forms and compositions tailored for tissue engineering are developed, but this approach just started to emerge in clinics. Biodegradable microparticles (MPs) made from degradable and biocompatible polymers, with a mean diameter of ~200 μm, are attractive not only as 3D matrices to multiply cells but also as a scaffold to support tissue rebuilding.
  • 617
  • 19 Apr 2022
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. 
  • 617
  • 08 Feb 2023
Topic Review
Polyelectrolyte–Dye Interactions
Polyelectrolytes are polymers with repeating units of ionizable groups coupled with counterions. Recently, polyelectrolytes have drawn significant attention as highly promising macromolecular materials with potential for applications in almost every sector of our daily lives. Dyes are another class of chemical compounds that can interact with substrates and subsequently impart color through the selective absorption of electromagnetic radiation in the visible range.
  • 613
  • 07 Feb 2022
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.
  • 613
  • 19 Feb 2024
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.
  • 613
  • 28 Jun 2022
Topic Review
Electronics Applications of P(VDF-TrFE) Composites
Piezoelectric polymers are a class of material that belong to carbon–hydrogen-based organic materials with a long polymer chain. They fill the void where single crystals and ceramics fail to perform. This characteristic of piezoelectric polymers made them unique. Their piezoelectric stress constant is higher than ceramics and the piezoelectric strain is lower compared to ceramics. 
  • 608
  • 20 Dec 2023
Topic Review
Polymer-Based Thermally Conductive Materials by Fused Filament Fabrication
With the miniaturization and integration of electronic products, the heat dissipation efficiency of electronic equipment needs to be further improved. Notably, polymer materials are a choice for electronic equipment matrices because of their advantages of low cost and wide application availability. Intelligent electronic devices are currently being researched to meet people’s pursuit of a high-quality life through integration and miniaturization. In order to ensure product safety and operational efficiency, it is imperative to improve the thermal conductivity of electronic devices. Polymers are frequently used in preparing heat dissipation materials because of their low price, light weight, ease of processing, and wide applications.
  • 600
  • 25 Oct 2022
Topic Review
Chitosan-Containing Composite Materials for Adsorption and Catalysis
Composite materials including organic–inorganic systems have drawn special attention due to their enhanced properties such as adsorbents and heterogeneous catalysts. At the same time, large-scale production of environmentally benign functionalized biopolymers, such as chitosan (CS), allows for constantly developing new materials, since CS reveals remarkable properties as a stabilizing agent for metal-containing compounds and enzymes and as an adsorbent of organic molecules. 
  • 594
  • 15 Mar 2023
Topic Review
Patchy Micelles via Crystallization-Driven Self-Assembly
Crystallization-driven self-assembly (CDSA) represents a highly versatile method for the production of well-defined block copolymer micelles in solution giving access to numerous tailor-made one-, two- and three-dimensional assemblies with controlled length, length distribution, shape, and corona chemistries. One special example of micelles derived by CDSA are the so-called patchy micelles, which possess a corona made of alternating nanometer-sized compartments. These patchy micelles show superior interfacial activity making them excellent candidates for the use as compatibilizers or metal (oxide) nanoparticle templates.
  • 593
  • 23 Jun 2021
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