Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Sustainable Polymeric Food Packaging Films
Food packaging is fundamental to ensuring food distribution and protection around the world, especially when considering the solid growth of the population. Without packaging, food would easily spoil and the distribution of enormous quantities of food, raw and processed, to different areas around the globe would hardly be possible.
  • 527
  • 16 Jan 2023
Topic Review
Surface Treatments of PEEK for Osseointegration to Bone
Polymers, in general, and Poly (Ether-Ether-Ketone) (PEEK) have emerged as potential alternatives to conventional osseous implant biomaterials. Due to its distinct advantages over metallic implants, PEEK has been gaining increasing attention as a prime candidate for orthopaedic and dental implants. Although a myriad of permutations and combinations of different surface treatments are employed to alter the surface topography of PEEK, for the sake of simplicity, these treatments have been classified into the following categories: physical treatment, chemical treatment, surface coating, and composite preparation, with the first surface treatment in the combination determining the classification. Though these terms are arbitrary and could lead to considerable overlap, physical and chemical treatments can be grouped into a subtractive form of surface modification while surface coating can be regarded as an additive form.
  • 217
  • 15 Mar 2023
Topic Review
Supramolecular Polymer Nanocomposites
Polymer nanocomposites, a class of innovative materials formed by polymer matrixes and nanoscaled fillers (e.g., carbon-based nanomaterials, inorganic/semiconductor nanoparticles, metal/metal-oxide nanoparticles, polymeric nanostructures, etc.), display enhanced mechanical, optoelectrical, magnetic, catalytic, and bio-related characteristics, thereby finding a wide range of applications in the biomedical field. In particular, the concept of supramolecular chemistry has been introduced into polymer nanocomposites, which creates myriad “smart” biomedical materials with unique physicochemical properties and dynamic tunable structures in response to diverse external stimuli. 
  • 705
  • 25 Feb 2021
Topic Review
Supercritical CO2 Foaming Technologies
Poly(lactic acid) (PLA) foaming is divided into physical foaming and chemical foaming; in contrast with the latter, the use of a physical foaming agent for PLA foaming has the characteristic of being green and non-polluting in line with the current carbon-neutral development plan. At the same time, the foam obtained by physical foaming has the properties of lightweight, low density, and more stable. Common physical blowing agents are CO2 and N2. Due to the plasticizing effect of CO2, and its high solubility in PLA, which can promote the crystallization of PLA, the current research on the supercritical foaming of PLA, especially intermittent foaming, mainly uses CO2 as the preferred foaming agent. However, due to the fast diffusion rate of N2, smaller bubbles can be obtained in microcellular injection foaming using N2. Therefore, N2 is commonly used as a blowing agent in the microcellular injection foaming process. In the supercritical foaming process, foaming parameters, such as saturation temperature, saturation pressure, and saturation time have a great influence on the structure and properties of the bubble pores. The cell diameter, cell density, and foam volume expansion ratio are three fundamental parameters for characterizing the cell structure. The variation in the three parameters has a great influence on the cell structure and the performance of the foam. Cell diameter generally refers to the average diameter of at least 100 cell units in the foaming image obtained from electron microscopy. Cell density refers to the number of cells per cubic centimeter of the foamed sample. Volume expansion ratio refers to the density ratio of the unfoamed sample to the foamed sample.
  • 882
  • 14 Nov 2022
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.
  • 742
  • 15 Nov 2022
Topic Review
Supercritical Carbon-di-Oxide Technology for Polymeric-Particles
Supercritical carbon dioxide (SC-CO2)  based techniques can be exploited for the formulation of polymeric nanocarriers, limiting the use of toxic organic solvent. The currently approved FDA pharmaceutical polymers like PLA and PLGA particles can be obtained in the micro-and nanometer range by techniques that involve SC-CO2 as solvent (RESS, RESOLV), anti-solvent (SAS, SEDS, SAILA) or extractant (SFEE), depending on the SC-CO2 compatibility with the system materials and the final product.
  • 509
  • 27 Apr 2021
Topic Review
Supercapacitor
Supercapacitors are electrical devices for fast storage and release of electric energy utilizing charge accumulation in the electrochemical double layer. In terms of volumetric and gravimetric capacities they exceed conventional dielectric and electrolytic capacitors by several orders of magnitude. However, the low energy density of supercapacitors has seriously limited their wider application in many fields. Increase of energy density highly depends on development of a new generation of advanced electrode materials for supercapacitors.
  • 1.8K
  • 26 Oct 2020
Topic Review
Sulfonimide-Based Dendrimers
Dendrimers are multifunctional polymer compounds with a tree-like shape and a high branching degree. 
  • 539
  • 25 Feb 2021
Topic Review
Structure-Oriented Design of Hyper-Crosslinked Porous Organic Nanomaterials
Hyper-crosslinked porous organic nanomaterials, especially the hyper-crosslinked polymers (HCPs), are a unique class of materials that combine the benefits of high surface area, porous structure, and good chemical and thermal stability all rolled into one. A wide range of synthetic methods offer an enormous variety of HCPs with different pore structures and morphologies, which has allowed HCPs to be developed for gas adsorption and separations, chemical adsorption and encapsulation, and heterogeneous catalysis. 
  • 167
  • 15 Oct 2023
Topic Review
Structural and Thermal Characterization of Resins
The synthesis of poly(vinylbenzyl pyridinium salts) fabricated through poly(vinylbenzyl halogene-co-divinylbenzene) quaternization of N-decyloxy-1-(pyridin-3- or -4-yl)ethaneimine was verified by the FTIR spectra of the final quaternized products, in comparison with the spectra of the initial copolymers.
  • 381
  • 17 Mar 2022
  • Page
  • of
  • 46
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Feedback