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Topic Review
Printable Hydrogels
The hydrogel is a hydrophilic scaffold composed of covalent and non-covalent polymeric chains bonds, providing a 3D shape environment similar to the native extra-cellular matrix (ECM).
  • 513
  • 18 Mar 2021
Topic Review
Preparation of Organosiloxane Telechelics by Cationic Ring-Opening Polymerization
Polydimethylsiloxanes (PDMS) telechelics are important both in industry and in academic research. They are used both in the free state and as part of copolymers and cross-linked materials. The most important, practically used, and well-studied method for the preparation of such PDMS is diorganosiloxane ring-opening polymerization (ROP) in the presence of nucleophilic or electrophilic initiators. Cationic ROP is also of interest for the preparation of functional PDMS. The advantage of this process is that it can be carried out at a relatively low temperature, the catalyst can be easily deactivated, and the process can also be used to synthesize polysiloxanes having base-sensitive substituents such as Si–H or Si–(CH2)3–SH.
  • 639
  • 24 Jun 2022
Topic Review
Preparation of Organosiloxane Telechelics by Anionic Ring-opening Polymerization
Polydimethylsiloxanes (PDMS) telechelics are important both in industry and in academic research. They are used both in the free state and as part of copolymers and cross-linked materials. The most important, practically used, and well-studied method for the preparation of such PDMS is diorganosiloxane ring-opening polymerization (ROP) in the presence of nucleophilic or electrophilic initiators. Anionic ring opening polymerization (AROP) under the action of various nucleophilic reagents is widely used for the synthesis of high molecular weight polydiorganosiloxane telechelics with various organic surroundings of the siloxane chain. In the process of cyclosiloxane opening and chain growth, side processes may occur: depolymerization due to the breaking of the linear chain by the active center (backbiting reaction) with the formation of low molecular weight cyclic products, and chain transfer reaction, in which the terminal active site attacks the siloxane bond of another polymer chain, leading to a redistribution of macromolecules, which is also called equilibration
  • 853
  • 24 Jun 2022
Topic Review
Positronium as a Probe of Polymer Free Volume
Positron annihilation lifetime spectroscopy (PALS) is a valuable technique to investigate defects in solids, such as vacancy clusters and grain boundaries in metals and alloys, as well as lattice imperfections in semiconductors. In the case of polymers, PALS is able to give information on the holes forming the free volume; this quantity, is correlated to important mechanical, thermal, and transport properties of polymers. PALS supplies a quantitative measure of the free volume by probing the corresponding sub-nanometric holes. The system used is positronium (Ps), an unstable atom formed by a positron and an electron, whose lifetime can be related to the typical size of the holes.
  • 291
  • 18 Sep 2023
Topic Review
Porous Carbon
Porous carbons are an important class of porous materials that have grown rapidly in recent years. They have the advantages of a tunable pore structure, good physical and chemical stability, a variable specific surface, and the possibility of easy functionalization.   
  • 4.0K
  • 29 Dec 2020
Topic Review
Pore-Selective Functionalization of HCP Films
Recent developments in the field of the breath figure (BF) method leading to pore-selective functionalization of honeycomb-patterned (HCP) films attracted great interest. The pore-selective functionalization of the HCP film gives unique properties to the film which can be used for specific applications like protein recognition, catalysis, selective cell culturing, and drug delivery.
  • 453
  • 06 Apr 2022
Topic Review
Polyvinylidene Fluoride-Graphene Oxide Membranes
In this study, polyvinylidene fluoride (PVDF)-graphene oxide (GO) membranes were obtained by employing triethyl phosphate (TEP) as a solvent. GO nanosheets were prepared and characterized in terms of scanning and transmission electron microscopy (SEM and TEM, respectively), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), chemical analysis and inductively coupled plasma mass spectroscopy (ICP).
  • 459
  • 18 May 2021
Topic Review
Polyvinyl Chloride in the Environment
Plastics have recently become an indispensable part of everyone’s daily life due to their versatility, durability, light weight, and low production costs. The increasing production and use of plastics poses great environmental problems due to their incomplete utilization, a very long period of biodegradation, and a negative impact on living organisms. Decomposing plastics lead to the formation of microplastics, which accumulate in the environment and living organisms, becoming part of the food chain. The contamination of soils and water with poly(vinyl chloride) (PVC) seriously threatens ecosystems around the world. Their durability and low weight make microplastic particles easily transported through water or air, ending up in the soil.
  • 593
  • 12 Jan 2024
Topic Review
Polyurethanes in Biomedicine
Due to their mechanical properties, ranging from flexible to hard materials, polyurethanes (PUs) have been widely used in many industrial and biomedical applications. PU characteristics, along with their biocompatibility, make them successful biomaterials in short and medium time applications.  The most important biomedical applications of PUs include antibacterial surfaces and catheters, blood oxygenators, dialysis devices, stents, cardiac valves, vascular prostheses, bioadhesives/surgical dressings/pressure sensitive adhesives, drug delivery systems, tissue engineering scaffolds and electrospinning, nerve generation, pacemaker lead insulation and coatings for breast implants. The diversity of polyurethane properties due to the ease of bulk and surface modification plays a vital role in their applications. 
  • 1.8K
  • 28 Oct 2020
Topic Review
Polyurethanes and Green Chemistry
Polyurethanes are most often called “green” when they contain natural, renewable additives in their network or chemical structure, such as mono- and polysaccharides, vegetable oils, polyphenols, or various compounds derived from agro-waste white biotechnology. The use of these natural substrates is in line with the principles of green chemistry. However, other principles among all 12 can also be used in the production of polyurethanes.
  • 777
  • 11 Nov 2021
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