描述
Diluent in colour additive mixts. for colouring shell eggs; coating, binder, plasticising agent and/or lubricant in tablets used for food; adjuvant to improve flavour and as a bodying agent in non-nutritive sweeteners; adjuvant in dispersing vitamin preparations; defoaming agent; boiler-water additive, etc.
Depending on the catalyst type, the mechanism of polymerization can be cationic or anionic. The anionic mechanism is preferable because it allows one to obtain PEG with a low polydispersity. Polymerization of ethylene oxide is an exothermic process. Overheating or contaminating ethylene oxide with catalysts such as alkalis or metal oxides can lead to runaway polymerization which can end with an explosion after few hours.; PEG is a popular precipitant for protein crystallization, X-ray diffraction of protein crystals can reveal the atomic structure of proteins.; PEG is traditionally also one of the main ingredients in Paintball fill because it is thick and flexible. However, as early as 2006, some Paintball manufacturers have been substituting PEG with cheaper alternatives.; PEGylation is the act of covalently coupling a PEG structure to another larger molecule, for example, a therapeutic protein (which is then referred to as PEGylated). PEGylated interferon alfa-2a or -2b is a commonly used injectable treatment for Hepatitis C infection.; Poly(ethylene glycol) (PEG), also known as poly(ethylene oxide) (PEO) or polyoxyethylene (POE), is the most commercially important type of polyether. PEG, PEO or POE refers to an oligomer or polymer of ethylene oxide. The three names are chemically synonymous, but historically PEG has tended to refer to oligomers and polymers with a molecular mass below 20,000 g/mol, PEO to polymers with a molecular mass above 20,000 g/mol, and POE to a polymer of any molecular mass. PEG and PEO are liquids or low-melting solids, depending on their molecular weights. PEGs are prepared by polymerization of ethylene oxide and are commercially available over a wide range of molecular weights from 300 g/mol to 10,000,000 g/mol. While PEG and PEO with different molecular weights find use in different applications and have different physical properties (e.g. viscosity) due to chain length effects, their chemical properties are nearly identical. Different forms of PEG are also available dependent on the initiator used for the polymerization process. The most common of which is a monofunctional methyl ether PEG (methoxypoly(ethylene glycol)), abbreviated mPEG. PEGs are also available with different geometries. Branched PEGs have 3 to 10 PEG chains emanating from a central core group. Star PEGs have 10 - 100 PEG chains emanating from a central core group. Comb PEGs have multiple PEG chains normally grafted to a polymer backbone.; Polyethylene glycol has a low toxicity and is used in a variety of products. It is the basis of a number of laxatives (e.g. macrogol-containing products such as Movicol and polyethylene glycol 3350, or SoftLax, MiraLax or GlycoLax). It is the basis of many skin creams, as cetomacrogol, and sexual lubricants, frequently combined with glycerin. Whole bowel irrigation (polyethylene glycol with added electrolytes) is used for bowel preparation before surgery or colonoscopy and drug overdoses. It is sold under the brand names GoLYTELY, NuLytely, GlycoLax, Fortrans, TriLyte, Colyte, Halflytely, MiraLAX, Softlax and MoviPrep. When attached to various protein medications, polyethylene glycol allows a slowed clearance of the carried protein from the blood. This makes for a longer acting medicinal effect and reduces toxicity, and it allows longer dosing intervals. Examples include PEG-interferon alpha, which is used to treat hepatitis C, and PEG-filgrastim (Neulasta), which is used to treat neutropenia. It has been shown that polyethylene glycol can improve healing of spinal injuries in dogs. One of the earlier findings that polyethylene glycol can aid in nerve repair came from the University of Texas (Krause and Bittner). Polyethylene glycol is commonly used to fuse B-cells with myeloma cells in monoclonal antibody production. PEG has recently been proved to give better results in constipation patients than tegaserod.; Since PEG is a flexible, water-soluble polymer, it can be used to create very high osmotic pressures (tens of atmospheres). It also is unlikely to have specific interactions with biological chemicals. These properties make PEG one of the most useful molecules for applying osmotic pressure in biochemistry experiments, particularly when using the osmotic stress technique.[citation needed]. Polyethylene glycol is found in many foods, some of which are turnip, mustard spinach, babassu palm, and watermelon.
InChI标识符
InChI=1S/C9H17NO3/c1-7(10)8(11)5-3-2-4-6-9(12)13/h7H,2-6,10H2,1H3,(H,12,13)