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Topic Review
Polymeric Emissive Materials Based on Dynamic Covalent Bonds
Dynamic covalent polymers, composed of dynamic covalent bonds (DCBs), have received increasing attention due to their adaptive and reversible nature compared with common covalent linked polymers. Incorporating the DCBs into the polymeric material endows it with advanced performance including self-healing, shape memory property, and so forth.
  • 1.6K
  • 25 Nov 2022
Topic Review
Mixed-Matrix Membranes for Gas Separation
Nanocomposite membranes, obtained by dispersing solid particles within a polymeric matrix, are referred to as mixed-matrix membranes (MMMs) and are potentially capable to exceed the trade-off restrictions between membrane permeability and selectivity, that is an intrinsic trait for polymeric membranes applied to gas separation. Making the most appropriate combination of filler and polymer is an exciting challenge for materials scientists.
  • 1.6K
  • 28 Jan 2022
Topic Review
Metal Complexes of the Porphyrin-Functionalized Polybenzoxazine
Porphyrin is a molecular material with many potential applications. New porphyrin-functionalized benzoxazine (Por-BZ) in high purity and yield was synthesized in this study based on 1H and 13C NMR and FTIR spectroscopic analyses through the reduction of Schiff base formed from tetrakis(4-aminophenyl)porphyrin (TAPP) and salicylaldehyde and the subsequent reaction with CH2O. Thermal properties of the product formed through ring-opening polymerization (ROP) of Por-BZ were measured using DSC, TGA and FTIR spectroscopy. Because of the rigid structure of the porphyrin moiety appended to the benzoxazine unit, the temperature required for ROP (314 °C) was higher than the typical Pa-type benzoxazine monomer (ca. 260 °C); furthermore, poly(Por-BZ) possessed a high thermal decomposition temperature (Td10 = 478 °C) and char yield (66 wt%) after thermal polymerization at 240 °C. An investigation of the thermal and luminescence properties of metal–porphyrin complexes revealed that the insertion of Ni and Zn ions decreased the thermal ROP temperatures of the Por-BZ/Ni and Por-BZ/Zn complexes significantly, to 241 and 231 °C, respectively. The metal ions acted as the effective promoter and catalyst for the thermal polymerization of the Por-BZ monomer, and also improved the thermal stabilities after thermal polymerization. 
  • 1.6K
  • 24 Feb 2022
Topic Review
Polymers in High-Efficiency Solar Cells
Third-generation solar cells, including dye-sensitized solar cells, bulk-heterojunction solar cells, and perovskite solar cells, are being intensively researched to obtain high efficiencies in converting solar energy into electricity. However, it is also important to note their stability over time and the devices’ thermal or operating temperature range. Today’s widely used polymeric materials are also used at various stages of the preparation of the complete device—it is worth mentioning that in dye-sensitized solar cells, suitable polymers can be used as flexible substrates counter-electrodes, gel electrolytes, and even dyes. In the case of bulk-heterojunction solar cells, they are used primarily as donor materials; however, there are reports in the literature of their use as acceptors. In perovskite devices, they are used as additives to improve the morphology of the perovskite, mainly as hole transport materials and also as additives to electron transport layers. Polymers, thanks to their numerous advantages, such as the possibility of practically any modification of their chemical structure and thus their physical and chemical properties, are increasingly used in devices that convert solar radiation into electrical energy.
  • 1.6K
  • 17 May 2022
Topic Review
Synthesis of Ferrocenyl Phosphorhydrazone Dendrimers
The discovery of ferrocene is often associated with the rapid growth of organometallic chemistry. Dendrimers are highly branched macromolecules that can be functionalized at will at all levels of their structure. The functionalization of dendrimers with ferrocene derivatives can be carried out easily as terminal functions on the surface, but also at the core, or at one or several layers inside the structure. Depending on the desired location of the ferrocenes in the structure of phosphorhydrazone dendrimers, the ferrocenes should be functionalized differently. For the grafting to the surface, the ferrocene should bear a phenol group, suitable to react in substitution reactions with the P(S)Cl2 terminal groups of the dendrimers. To be used as core, the ferrocene should have two aldehyde functions, from which the synthesis of the dendrimer will be carried out. To be introduced in the branches, at all layers or within a single layer, the ferrocene should replace hydroxybenzaldehyde; thus, it should bear both a phenol and an aldehyde.
  • 1.6K
  • 06 Jun 2022
Topic Review
SAPO-34 Zeolite Membranes
In the zeolite family, the silicoaluminophosphate (SAPO)-34 zeolite has a unique chemical structure, distinctive pore size, adsorption characteristics, as well as chemical and thermal stability, has attracted much research attention. Increasing global carbon dioxide (CO2) emissions pose a serious environmental threat to humans, animals, plants, and the entire environment.
  • 1.6K
  • 20 Mar 2023
Topic Review
Natural Antibacterial Additives in Bioactive Wound Dressings
Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs.
  • 1.5K
  • 10 Mar 2023
Topic Review
3D Printing Technologies in Dentistry
3D-printing application in dentistry not only enables the manufacture of patient-specific devices and tissue constructs, but also allows mass customization, as well as digital workflow, with predictable lower cost and rapid turnaround times.
  • 1.5K
  • 16 Sep 2022
Topic Review
Hip Implant Applications
Three-dimensional (3D) printing offers significant potential as an efficient fabrication technique on personalized organs as it is capable of biomimicking the intricate designs found in nature. In this review, the determining factors for hip replacement and the different fabrication techniques such as direct 3D printing, Fused Deposition Modelling (FDM), Selective Laser Sintering (SLS) and stereolithography (SLA) for hip replacement. The study also covers surface modifications of 3D printed implants and provides an overview on 3D tissue regeneration. To appreciate the current conventional hip replacement practices, the conventional metallic and ceramic materials are covered, highlighting their rationale as the material of choice. Next, the challenges, ethics and trends in the implants’ 3D printing, outlook and challenges are also presented. 
  • 1.5K
  • 26 Nov 2020
Topic Review
Supercritical CO2
Supercritical CO2 (scCO2) is an alternative promising solvent that has been actively used in recent decades to simplify many processes of polymer synthesis, modification, decomposition, etc.
  • 1.5K
  • 15 Nov 2022
Topic Review
Antimicrobial Properties of Lignocellulosic Materials
Pathogenic microbes are a major source of health and environmental problems, mostly due to their easy proliferation on most surfaces. Currently, new classes of antimicrobial agents are under development to prevent microbial adhesion and biofilm formation. However, they are mostly from synthetic origin and present several disadvantages. The use of natural biopolymers such as cellulose, hemicellulose, and lignin, derived from lignocellulosic materials as antimicrobial agents has a promising potential. Lignocellulosic materials are one of the most abundant natural materials from renewable sources, and they present attractive characteristics, such as low density and biodegradability, are low-cost, high availability, and environmentally friendly.
  • 1.5K
  • 08 Apr 2021
Topic Review
Enzyme-Catalyzed Synthesis of Polyesters
Polyester is a kind of polymer composed of ester bond-linked polybasic acids and polyol. This type of polymer has a wide range of applications in various industries, such as automotive, furniture, coatings, packaging, and biomedical. The traditional process of synthesizing polyester mainly uses metal catalyst polymerization under high-temperature. This condition may have problems with metal residue and undesired side reactions. As an alternative, enzyme-catalyzed polymerization is evolving rapidly due to the metal-free residue, satisfactory biocompatibility, and mild reaction conditions.   
  • 1.5K
  • 20 Dec 2022
Topic Review
Magnetic Polymers for Microfluidic Sorting
Magnetophoresis offers many advantages for manipulating magnetic targets in microsystems. The integration of micro-flux concentrators and micro-magnets allows achieving large field gradients and therefore large reachable magnetic forces. However, the associated fabrication techniques are often complex and costly, and besides, they put specific constraints on the geometries. Magnetic composite polymers provide a promising alternative in terms of simplicity and fabrication costs, and they open new perspectives for the microstructuring, design, and integration of magnetic functions.
  • 1.5K
  • 30 Jul 2021
Topic Review
High-Voltage Film Capacitors
High-voltage capacitors are key components for circuit breakers and monitoring and protection devices, and are important elements used to improve the efficiency and reliability of the grid. Different technologies are used in high-voltage capacitor manufacturing process, and at all stages of this process polymeric films must be used, along with an encapsulating material, which can be either liquid, solid or gaseous.
  • 1.5K
  • 24 Mar 2021
Topic Review
Food Bio-Based Packaging
Recently, academic research and industries have gained awareness about the economic, environmental, and social impacts of conventional plastic packaging and its disposal. This consciousness has oriented efforts towards more sustainable materials such as biopolymers, paving the way for the “green era” of food packaging.
  • 1.5K
  • 27 Oct 2022
Topic Review
Thermoresponsive Polypeptoids
Thermoresponsive polypeptoids exhibiting a reversible phase transition in a controlled manner to temperature are a promising class of smart polymers that have drawn growing interest because of its excellent biocompatibility, biodegradability, and bioactivity. The phase transition behavior of these polymers can be tuned by polymer architectures, chain-end, and various functional groups. 
  • 1.5K
  • 29 Dec 2020
Topic Review
Polyurea Aerogels
The term “aerogel” describes a certain class of low-density solid materials with a high open porosity. Aerogels can be considered to be a subclass of the much broader domain of porous materials; however, they are distinguished from, for example, blown foams, because they are prepared in a completely different manner—namely, by drying wet gels in a way that preserves nearly all of their volume in the final dry form.
  • 1.5K
  • 02 Apr 2022
Topic Review
Applications of High Molecular Weight Poly(Methyl Methacrylate)
Poly(methyl methacrylate) (PMMA), commonly known as plexiglass, is a kind of polymer synthesized by free radical polymerization, ionic polymerization and coordination polymerization. Poly(methyl methacrylate) (PMMA) is widely used in aviation, architecture, medical treatment, optical instruments and other fields because of its good transparency, chemical stability and electrical insulation.
  • 1.5K
  • 12 Jul 2022
Topic Review
Polypropylene Extrusion Molding Production Quality
Polypropylene is derived from the reaction of petrochemical propylene gas with a density of 0.89–0.94 g/cm3. It is a lightweight plastic material with a semitransparent white color and has a lower cost than other plastic materials.
  • 1.5K
  • 02 Jun 2022
Topic Review
Chitosan-Based Polyurethane Flexible Foams
Polyurethane (PUR) foam is a synthetic polymer.
  • 1.5K
  • 14 Sep 2021
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