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Topic Review
Biography
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.
694
11 Jul 2022
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.
649
02 Apr 2022
Topic Review
Polystyrene vs. Polylactide
Polystyrene (PS) is a thermoplastic polymer made of aromatic hydrocarbon monomer styrene that is derived from fossil-fuels. The synthesis of PS is based on the free radical polymerization of styrene using free-radical initiators. It is mostly used in solid (high impact and general purpose PS), foam and expanded PS forms. The main advantages of PS are low-cost, easy processing ability, and resistance to ethylene oxide, as well as radiation sterilization. Polylactide (PLA)—biodegradable and compostable aliphatic polyester—is one of the key biopolymers with the largest market significance.
2.4K
28 Dec 2022
Topic Review
Polysiloxane-Based Ionic Polymers
A diverse range of linear polysiloxane-based ionic polymers that are hydrophobic and highly flexible can be obtained by substituting the polymers with varying amounts of ionic centers. The materials can be highly crystalline solids, amorphous soft solids, poly(ionic) liquids or viscous polymer liquids.
1.6K
31 Dec 2020
Topic Review
Polysaccharides in Agro-Industrial Biomass Residues
The use of waste biomass to produce biopolymers and nutricosmetic or pharmacological materials is increasing, although still scarcely compared to its great potential, employment, and valorization. Organic waste biomass is a great source of natural polysaccharides such as cellulose, chitin, hyaluronic acid, inulin, and pectin. Biomass from the agricultural sectors is a relevant part of waste generation and commonly comprises leaves, roots, stalks, bark, bagasse, seeds, straw, wood, animal parts, crustacean shells, and others. Polysaccharides are the most abundant biological materials on the planet. This natural abundance contributes to the discovery of their novel applications. Their industrial use is still very modest considering their versatility and great potential, although it has recently seen significant increases.
826
18 Mar 2022
Topic Review
Polysaccharide-Based Hydrogels Drug Delivery in Cancer Therapy
Hydrogels are three-dimensional crosslinked structures with physicochemical properties similar to the extracellular matrix (ECM). By changing the hydrogel’s material type, crosslinking, molecular weight, chemical surface, and functionalization, it is possible to mimic the mechanical properties of native tissues. Hydrogels are currently used in the biomedical and pharmaceutical fields for drug delivery systems, wound dressings, tissue engineering, and contact lenses. Polysaccharide-based hydrogels can be used as drug delivery systems for the efficient release of various types of cancer therapeutics, enhancing the therapeutic efficacy and minimizing potential side effects.
417
01 Feb 2023
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.
279
12 Mar 2024
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.
695
02 Jun 2022
Topic Review
Polyphenylsulfone Membrane
Polyphenylsulfone (PPSU) membranes are of fundamental importance for many applications such as water treatment, gas separation, energy, electronics, and biomedicine, due to their low cost, controlled crystallinity, chemical, thermal, and mechanical stability. Numerous research studies have shown that modifying surface properties of PPSU membranes influences their stability and functionality. Therefore, the modification of the PPSU membrane surface is a pressing issue for both research and industrial communities.
1.5K
10 Mar 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.
930
17 May 2022
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