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Topic Review
Design and Synthesis of Sidechain Phosphorus-Containing Polyacids
Macromolecules containing acidic fragments in side-groups—polyacids—occupy a special place among synthetic polymers. Properties and applications of polyacids are directly related to the chemical structure of macromolecules: the nature of the acidic groups, polymer backbone, and spacers between the main chain and acidic groups. The chemical nature of the phosphorus results in the diversity of acidic >P(O)OH fragments in sidechain phosphorus-containing polyacids (PCPAs) that can be derivatives of phosphoric or phosphinic acids.
  • 1.6K
  • 13 Feb 2023
Topic Review
Alginate Microparticles for Food, Pharmaceutical and Cosmetic Applications
Alginates are the most widely used natural polymers in the pharmaceutical, food and cosmetic industries. Usually, they are applied as a thickening, gel-forming and stabilizing agent. Moreover, the alginate-based formulations such as matrices, membranes, nanospheres or microcapsules are often used as delivery systems. Alginate microparticles (AMP) are biocompatible, biodegradable and nontoxic carriers, applied to encapsulate hydrophilic active substances, including probiotics.
  • 1.6K
  • 21 Oct 2022
Topic Review
Cellulose-Based Hydrogels
Hydrogels, three-dimensional (3D) polymer networks, present unique properties, like biocompatibility, biodegradability, tunable mechanical properties, sensitivity to various stimuli, the capacity to encapsulate different therapeutic agents, and the ability of controlled release of the drugs.
  • 1.6K
  • 28 Jan 2021
Topic Review
Organosolv Lignin-Based Polyurethane
Polyurethanes (PUs) present an important class of polymers due to outstanding mechanical, chemical and physical properties. Thus, they find application in many industrial sectors in the form of flexible or rigid foams, coatings, adhesives, elastomers, thermoplasts or thermosets. Modern PU coating applications include self-healing coating films that can also be applied to rather rough surfaces, such as wood.
  • 1.6K
  • 22 Mar 2022
Topic Review
General Characteristics of Chitosan
Chitosan is a naturally occurring compound that can be obtained from deacetylated chitin, which is obtained from various sources such as fungi, crustaceans, and insects. Commercially, chitosan is produced from crustaceans. Based on the range of its molecular weight, chitosan can be classified into three different types, namely, high molecular weight chitosan (HMWC, >700 kDa), medium molecular weight chitosan (MMWC, 150–700 kDa), and low molecular weight chitosan (LMWC, less than 150 kDa).
  • 1.6K
  • 14 Jul 2023
Topic Review
Lignin as Renewable Building Block for Sustainable Polyurethanes
Lignin, being a natural aromatic polymer rich in functional hydroxyl groups, has been drawing the interest of academia and industry for its valorization, especially for the development of polymeric materials. Among the different types of polymers that can be derived from lignin, polyurethanes (PUs) are amid the most important ones, especially due to their wide range of applications. Lignin, being a natural aromatic polymer rich in functional hydroxyl groups, has been drawing the interest of academia and industry for its valorization, especially for the development of polymeric materials. Among the different types of polymers that can be derived from lignin, polyurethanes (PUs) are amid the most important ones, especially due to their wide range of applications. 
  • 1.6K
  • 20 Oct 2022
Topic Review
Polyester Fibrous Panels
Nowadays, polyester fibrous materials are becoming one of the most important alternatives for controlling reverberation time by absorbing unwanted sound energy in the automobile and construction fields. The polyester nonwoven structure used in noise reduction is normally in the form of panel.
  • 1.6K
  • 09 Nov 2020
Topic Review
Biodegradable Polymers
Biodegradable polymers are those which can degrade into water and carbon dioxide under normal environmental conditions through microbial action, providing compost as a simple and sustainable disposal option.
  • 1.6K
  • 17 Jan 2022
Topic Review
Microcellular Injection Moulding
Microcellular injection moulding (MuCell®) is a polymer processing technology that uses a supercritical fluid inert gas, CO2 or N2, to produce light-weight products. Due to environmental pressures and the requirement of light-weight parts with good mechanical properties, this technology recently gained significant attention. However, poor surface appearance and limited mechanical properties still prevent the wide applications of this technique.
  • 1.6K
  • 16 Aug 2021
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-. 
  • 1.6K
  • 17 Oct 2022
Topic Review
Smart Bioinks for Printing Human Tissue Models
A bioink is a mixture of materials and biological molecules or cells to be used for bioprinting. Most bioinks are hydrogels, highly hydrated polymeric networks used to homogenously encapsulate cells by mimicking the natural extracellular matrix found in vivo. Hydrogels must meet certain characteristics to ensure they can support cell survival and function.
  • 1.6K
  • 25 Apr 2022
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.
  • 1.6K
  • 24 Apr 2023
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
Polymeric Pipeline Coatings Time-Dependent Performance
The barrier performance of organic coatings is a direct function of mass transport and long-term stability of the polymeric structure. A predictive assessment of the protective coating cannot be conducted a priori of degradation effects on transport. Epoxy-based powder coatings are an attractive class of coatings for pipelines and other structures because application processing times are low and residual stresses between polymer layers are reduced. 
  • 1.6K
  • 27 May 2021
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. 
  • 1.5K
  • 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.
  • 1.5K
  • 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.
  • 1.5K
  • 06 Jun 2022
Topic Review
Cascading Recycling of Wood Waste
Wood wastes are divided into two main categories: industrial wastes generated within the industry and final wastes, after use of the products.
  • 1.5K
  • 09 Jun 2021
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
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. 
  • 1.5K
  • 20 Dec 2023
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