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In interventional radiology, Onyx is a trade name for a copolymer used for embolisation therapy, [1] which involves the occlusion of blood vessels. It is a liquid embolic agent. Onyx is produced and sold by Medtronic (previously Covidien, which acquired ev3 Inc., the original developer of Onyx, in 2010).
Onyx consists of Ethylene Vinyl Alcohol Copolymer, soluted in Dimethyl-Sulfoxide (DMSO). Depending on the desired character of the liquid, the concentration can be varied: For example, 6% EVOH (trade name Onyx 18) or 8% EVOH (trade name Onyx 34). Micronized tantalum powder is added in order to maintain Radiopacity. [2]
Onyx was approved as 'Humanitarian Use Device (HUD)' for the treatment of saccular aneurysms that are not surgically removable by the Food and Drug Administration (FDA) in the United States on April 11, 2007. [3] [4]
Ethanol is a chemical compound, a simple alcohol with the chemical formula C
2H
6O. Its formula can be also written as CH
3−CH
2−OH or C
2H
5OH, and is often abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. It is a psychoactive substance and is the principal active ingredient found in alcoholic drinks.
Petrochemicals are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as corn, palm fruit or sugar cane.
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most common plastic. As of 2017, over 100 million tonnes of polyethylene resins are produced annually, accounting for 34% of the total plastics market. Its primary use is in packaging (plastic bags, plastic films, geomembranes, containers including bottles, etc.). Many kinds of polyethylene are known, with most having the chemical formula (C2H4)n. PE is usually a mixture of similar polymers of ethylene with various values of n. Polyethylene is a thermoplastic; however, it can become a thermoset plastic when modified (such as cross-linked polyethylene).
Poly(vinyl acetate) (PVA, PVAc, poly(ethenyl ethanoate): best known as wood glue, white glue, carpenter's glue, school glue, Elmer's glue in the US, or PVA glue) is an aliphatic rubbery synthetic polymer with the formula (C4H6O2)n. It belongs to the polyvinyl ester family, with the general formula -[RCOOCHCH2]-. It is a type of thermoplastic. There is considerable confusion between the adhesive as purchased, an aqueous emulsion of mostly polyvinyl acetate, and the subsequently dried material, which is still polyvinyl acetate and chemically unchanged, that is erroneously thought of as the newly polymerized product.needs citation
Onyx is a banded variety of chalcedony (quartz).
An elastomer is a polymer with viscoelasticity and has very weak intermolecular forces, generally low Young's modulus and high failure strain compared with other materials. The term, a portmanteau of elastic polymer, is often used interchangeably with rubber, although the latter is preferred when referring to vulcanisates. Each of the monomers which link to form the polymer is usually a compound of several elements among carbon, hydrogen, oxygen and silicon. Elastomers are amorphous polymers maintained above their glass transition temperature, so that considerable molecular reconformation, without breaking of covalent bonds, is feasible. At ambient temperatures, such rubbers are thus relatively soft and deformable. Their primary uses are for seals, adhesives and molded flexible parts. Application areas for different types of rubber are manifold and cover segments as diverse as tires, soles for shoes, and damping and insulating elements. The importance of these rubbers can be judged from the fact that global revenues are forecast to rise to US$56 billion in 2020.
Embolization refers to the passage and lodging of an embolus within the bloodstream. It may be of natural origin (pathological), in which sense it is also called embolism, for example a pulmonary embolism; or it may be artificially induced (therapeutic), as a hemostatic treatment for bleeding or as a treatment for some types of cancer by deliberately blocking blood vessels to starve the tumor cells.
Ethylene-vinyl acetate (EVA), also known as poly (PEVA), is the copolymer of ethylene and vinyl acetate. The weight percent vinyl acetate usually varies from 10 to 40%, with the remainder being ethylene.
Vinyl acetate is an organic compound with the formula CH3CO2CH=CH2. This colorless liquid is the precursor to polyvinyl acetate, an important industrial polymer.
Hot melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly sold as solid cylindrical sticks of various diameters designed to be applied using a hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which the user pushes through the gun either with a mechanical trigger mechanism on the gun, or with direct finger pressure. The glue squeezed out of the heated nozzle is initially hot enough to burn and even blister skin. The glue is tacky when hot, and solidifies in a few seconds to one minute. Hot melt adhesives can also be applied by dipping or spraying, and are popular with hobbyists and crafters both for affixing and as an inexpensive alternative to resin casting.
2-Chloroethanol is a chemical compound with the formula HOCH2CH2Cl and the simplest chlorohydrin. This colorless liquid has a pleasant ether-like odor. It is miscible with water. The molecule is bifunctional, consisting of both an alkyl chloride and an alcohol functional groups.
A carotid-cavernous fistula results from an abnormal communication between the arterial and venous systems within the cavernous sinus in the skull. It is a type of arteriovenous fistula. As arterial blood under high pressure enters the cavernous sinus, the normal venous return to the cavernous sinus is impeded and this causes engorgement of the draining veins, manifesting most dramatically as a sudden engorgement and redness of the eye of the same side.
Vacuum packing is a method of packaging that removes air from the package prior to sealing. This method involves placing items in a plastic film package, removing air from inside, and sealing the package. Shrink film is sometimes used to have a tight fit to the contents. The intent of vacuum packing is usually to remove oxygen from the container to extend the shelf life of foods and, with flexible package forms, to reduce the volume of the contents and package.
Salt End or Saltend is a hamlet in the East Riding of Yorkshire, England, in an area known as Holderness. It is situated on the north bank of the Humber Estuary just outside the Hull eastern boundary on the A1033 road. It forms part of the civil parish of Preston.
Ethyl acrylate is an organic compound with the formula CH2CHCO2CH2CH3. It is the ethyl ester of acrylic acid. It is a colourless liquid with a characteristic acrid odor. It is mainly produced for paints, textiles, and non-woven fibers. It is also a reagent in the synthesis of various pharmaceutical intermediates.
Ethylene vinyl alcohol (EVOH) is a formal copolymer of ethylene and vinyl alcohol. Because the latter monomer mainly exists as its tautomer acetaldehyde, the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate (EVA) copolymer followed by hydrolysis. EVOH copolymer is defined by the mole % ethylene content: lower ethylene content grades have higher barrier properties; higher ethylene content grades have lower temperatures for extrusion.
A polymeric foam is a foam, in liquid or solidified form, formed from polymers.
Graft polymers are segmented copolymers with a linear backbone of one composite and randomly distributed branches of another composite. The picture labeled "graft polymer" shows how grafted chains of species B are covalently bonded to polymer species A. Although the side chains are structurally distinct from the main chain, the individual grafted chains may be homopolymers or copolymers. Graft polymers have been synthesized for many decades and are especially used as impact resistant materials, thermoplastic elastomers, compatibilizers, or emulsifiers for the preparation of stable blends or alloys. One of the more well known examples of a graft polymer is high impact polystyrene, which consists of a polystyrene backbone with polybutadiene grafted chains.
Chemence is a multinational conglomerate which manufactures products including cyanoacrylate adhesives, anaerobic adhesives, impregnation sealants, adhesive activators, epoxy resins, UV adhesives, photopolymer resins, custom printer ink cartridges, Gas pipe sealants, and soak off nail polishes. Chemence is a supplier of photopolymer and commercial printers to the flexographic industry in the US and Europe, as well as the primary sealant supplier to British Gas, and a primary supplier of private-label adhesives to companies including Tesco, 3M, Bostik, and Bondo. The company's catalogue of patents includes processes, packaging devices, and chemical combinations.
Vinyl propionate is the organic compound with the formula CH3CH2CO2CH=CH2. This colorless liquid is the ester of propionic acid and vinyl alcohol. It is used to produce poly(vinyl propionate) as well as copolymers with acrylate esters, vinyl chloride, and vinyl acetate, some of which are used in paints. The compound resembles vinyl acetate.