query: What is propylene glycol?

title: Propylene glycol

text: in many pharmaceuticals, including oral, injectable and topical formulations, such as for diazepam and lorazepam which are insoluble in water. Certain formulations of artificial tears, such as Systane, use proplyene glycol as an ingredient. Like ethylene glycol, propylene glycol is able to lower the freezing point of water, and so it is used as aircraft de-icing fluid. Water-propylene glycol mixtures dyed pink to indicate the mixture is relatively nontoxic are sold under the name of RV or marine antifreeze. Propylene glycol is frequently used as a substitute for ethylene glycol in low toxicity, environmentally friendly automotive antifreeze. It is also

title: Propylene glycol

text: Glycerin (VG), of the e-liquid and cartridges used in electronic cigarettes where it is aerosolized in the atomizer. It is also used in model railway and model boat applications to simulate steam or smoke, using a small heating element. Propylene glycol is also used in various edible items such as coffee-based drinks, liquid sweeteners, ice cream, whipped dairy products and soda. Vaporizers used for delivery of pharmaceuticals or personal-care products often include propylene glycol among the ingredients. In alcohol-based hand sanitizers, it is used as a humectant to prevent the skin from drying. Propylene glycol is used as a solvent

title: Propylene glycol

text: a solute in a solvent (freezing-point depression). In general, glycols are non-corrosive, have very low volatility and very low toxicity; however, the closely related ethylene glycol (a key ingredient in antifreeze) is toxic to humans and to many animals. Industrially, propylene glycol is produced from propylene oxide (for food-grade use), and global capacity in 1990 was 900,000 tonnes per year. Different manufacturers use either non-catalytic high-temperature process at to , or a catalytic method, which proceeds at to in the presence of ion exchange resin or a small amount of sulfuric acid or alkali. Final products contain 20% propylene glycol,

title: Propylene glycol

text: antifreeze solutions for emergency eye wash stations. This is of particular concern however, due to the relatively new trend of "vaping", also known as use of e-cigarettes, due to many of the commercially available "juice" products containing propylene glycol as a key ingredient, along with varying concentrations of nicotine & other chemicals, and it being repetitively inhaled by e-cigarette users. According to a 2010 study by Karlstad University, the concentrations of PGEs (counted as the sum of propylene glycol and glycol ethers) in indoor air, particularly bedroom air, has been linked to increased risk of developing numerous respiratory and immune

title: Propylene glycol

text: Propylene glycol Propylene glycol (IUPAC name: propane-1,2-diol) is a synthetic organic compound with the chemical formula CHO. It is a viscous, colorless liquid which is nearly odorless but possesses a faintly sweet taste. Chemically it is classed as a diol and is miscible with a broad range of solvents, including water, acetone, and chloroform. It is produced on a large scale and is primarily used in the production of polymers, but also sees use in food processing, and as a process fluid in low-temperature heat-exchange applications. In the European Union, it has the E-number E1520 for food applications. For cosmetics

title: Glycol Chillers

text: USP grade to ensure it is recommended for food use. Glycol Chillers Glycol chillers are specialized refrigeration systems, and often involves the use of antifreeze. A popular application is in beverage production, wherein the food grade chemical propylene glycol is used. Glycol chillers are a specific kind of refrigeration system, often used to cool a variety of liquids, including alcohol and other beverages. Using a chiller allows producers to lower the temperature of the product dramatically over a short period of time, depending on the production needs. Propylene glycol plays a significant role in the application of a glycol chiller.

title: Glycol Chillers

text: Glycol Chillers Glycol chillers are specialized refrigeration systems, and often involves the use of antifreeze. A popular application is in beverage production, wherein the food grade chemical propylene glycol is used. Glycol chillers are a specific kind of refrigeration system, often used to cool a variety of liquids, including alcohol and other beverages. Using a chiller allows producers to lower the temperature of the product dramatically over a short period of time, depending on the production needs. Propylene glycol plays a significant role in the application of a glycol chiller. For cooling in brewing, there are few processes where decreasing

title: Ethylene glycol

text: containing propylene glycol in place of ethylene glycol are available. They are generally considered safer to use, as propylene glycol does not taste as good and is converted in the body to lactic acid, a normal product of metabolism and exercise. Australia, the UK, and seventeen US states (as of 2012) require the addition of a bitter flavoring (denatonium benzoate) to antifreeze. In December 2012, US antifreeze manufacturers agreed voluntarily to add a bitter flavoring to all antifreeze that is sold in the consumer market of the US. Ethylene glycol is a high-production-volume chemical; it breaks down in air in

title: Glycol Chillers

text: or maintaining temperature are important - like crash cooling a beer after fermentation, or keeping a steady temperature during fermentation (which generates heat), or cooling the wort after an initial boiling process. A chiller is essentially a refrigerator that includes a compressor, evaporator, condenser and a metering device. An additional buffer tank is used with the chilling unit to provide additional system capacity to prevent excessive cycling, unexpected temperature fluctuations, and erratic system operation. Propylene glycol, a food-grade antifreeze, is typically used when consumable products are involved. Before using glycol in the brewing process, check that propylene glycol is of

title: Glycol ethers

text: "e-series" or "p-series" glycol ethers, depending on whether they are made from ethylene oxide or propylene oxide, respectively. Typically, e-series glycol ethers are found in pharmaceuticals, sunscreens, cosmetics, inks, dyes and water-based paints, while p-series glycol ethers are used in degreasers, cleaners, aerosol paints and adhesives. Both E-series glycol ethers and P-series glycol ethers can be used as intermediates that undergo further chemical reactions, producing glycol diethers and glycol ether acetates. P-series glycol ethers are marketed as having lower toxicity than the E-series. Most glycol ethers are water-soluble, biodegradable and only a few are considered toxic. One study suggests that

title: Diethylene glycol

text: are likely to suffer significant morbidity. The physical properties of diethylene glycol make it an excellent counterfeit for pharmaceutical-grade glycerine (also called glycerol) or propylene glycol, and has caused many deaths in different countries. Incidents include its use in China as a component of cheap toothpaste, and by winemakers in Europe as an adulterant to create a "sweet" wine. In 1937, S.E. Massengill Co. (a Tennessee drug company), manufactured sulfanilamide dissolved with diethylene glycol, to create a liquid alternative of this drug. The company tested the new product, Elixir Sulfanilamide, for viscosity, appearance and fragrance. At the time, the food

title: Ethylene glycol poisoning

text: these crystals may not be present until the late stages of poisoning. Finally, many commercial radiator antifreeze products have fluorescein added to enable radiator leaks to be detected using a Wood's lamp. Following ingestion of antifreeze products containing ethylene glycol and fluorescein, a Wood's lamp may reveal fluorescence of a patient’s mouth area, clothing, vomitus, or urine which can help to diagnose poisoning. Antifreeze products for automotive use containing propylene glycol in place of ethylene glycol are available, and are generally considered safer to use, as it possesses an unpleasant taste in contrast to the perceived "sweet" taste of toxic

title: Diethylene glycol

text: suspect paracetamol syrup, samples were shipped to the Centers for Disease Control and Prevention (CDC) in the U.S., which identified DEG. It was assumed that DEG was used as a substitute of propylene glycol, and this incident encouraged the Nigerian government to develop pharmaceutical quality control guidelines. In Bangladesh between 1990 and 1992, 339 children developed kidney failure, and most of them died, after being given paracetamol (acetaminophen) syrup contaminated with diethylene glycol. The outbreak forced the government to ban the sale of paracetamol elixirs in December 1992, causing a decline of 53% in the admission of patients with renal

title: Cryoprotectant

text: than single-agent cryoprotectants. A mixture of formamide with DMSO (dimethyl sulfoxide), propylene glycol, and a colloid was for many years the most effective of all artificially created cryoprotectants. Cryoprotectant mixtures have been used for vitrification (i.e. solidification without crystal ice formation). Vitrification has important applications in preserving embryos, biological tissues and organs for transplant. Vitrification is also used in cryonics, in an effort to eliminate freezing damage. Conventional cryoprotectants are glycols (alcohols containing at least two hydroxyl groups), such as ethylene glycol , propylene glycol and glycerol. Ethylene glycol is commonly used as automobile antifreeze; while propylene glycol has been

title: Antifreeze

text: kidney failure can result within 72 hours if the individual does not receive appropriate medical treatment for the poisoning. Some ethylene glycol antifreeze mixtures contain an embittering agent, such as denatonium, to discourage accidental or deliberate consumption. Propylene glycol is considerably less toxic than ethylene glycol and may be labeled as "non-toxic antifreeze". It is used as antifreeze where ethylene glycol would be inappropriate, such as in food-processing systems or in water pipes in homes where incidental ingestion may be possible. For example, the FDA allows propylene glycol to be added to a large number of processed foods, including ice

title: Ethylene glycol

text: Ethylene glycol Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound with the formula (CHOH). It is mainly used for two purposes, as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odorless, colorless, sweet-tasting, viscous liquid. Ethylene glycol is highly toxic. Household pets are especially susceptible to ethylene glycol poisoning from vehicle antifreeze leaks. Ethylene glycol is produced from ethylene (ethene), via the intermediate ethylene oxide. Ethylene oxide reacts with water to produce ethylene glycol according to the chemical equation: This reaction can be catalyzed by either acids or bases, or can

title: Glycol distearate

text: increase the visual appeal of their products. It may also act as a skin moisturizer. Glycol distearate is also commonly used as an embedding agent in microscopy. Glycol distearate Glycol distearate is the diester of stearic acid and ethylene glycol. It is mostly commonly encountered in personal care products and cosmetics where it is used to produce pearlescent effects as well as a moisturizer. Glycol distearate may be produced via the esterification of stearic acid (or its esters) with ethylene glycol. It can also be produced by a reaction of stearic acid with ethylene oxide. When forced to crystalize as

title: Glycol distearate

text: Glycol distearate Glycol distearate is the diester of stearic acid and ethylene glycol. It is mostly commonly encountered in personal care products and cosmetics where it is used to produce pearlescent effects as well as a moisturizer. Glycol distearate may be produced via the esterification of stearic acid (or its esters) with ethylene glycol. It can also be produced by a reaction of stearic acid with ethylene oxide. When forced to crystalize as thin platelets glycol distearate can give liquids and gels a pearlescent appearance. This is often used by the producers of personal care products (e.g. shower gel) to

title: Antifreeze

text: Before the 1950s, coolant systems were unpressurized and the engine was often cooler than modern automotive engines. By pressurizing the coolant system with a radiator cap, the boiling point of the fluid is increased, permitting higher engine temperatures and better fuel efficiency. Pressurized systems do not appreciably change the freezing point. Later propylene glycol was introduced due to its environmental credentials. The most common water-based antifreeze solutions used in electronics cooling are mixtures of water and either ethylene glycol (EGW) or propylene glycol (PGW). The use of ethylene glycol has a longer history, especially in the automotive industry. However, EGW

title: Diethylene glycol

text: glycol can also be used as a cryoprotectant; however, ethylene glycol is much more commonly used. Most ethylene glycol antifreeze contains a few percent diethylene glycol, present as an byproduct of ethylene glycol production. Despite the discovery of DEG’s toxicity in 1937 and its involvement in mass poisonings around the world, the information available regarding human toxicity is limited. Some authors suggest the minimum toxic dose is estimated at 0.14 mg/kg of body weight and the lethal dose is between 1.0 and 1.63 g/kg of body weight, while some suggest the LD in adults is of ~1 mL/kg, and others

title: Fog machine

text: fog machine. Upon exiting the fog machine and mixing with cooler outside air the vapor condenses, resulting in a thick visible fog. Heated fog machines use either an inert gas or an electric pump to propel mineral oil, propylene glycol, or glycerin and water mixture into a heat exchanger, where the solution is vaporized. Propylene glycol is used rather than ethylene glycol (ie antifreeze), as the latter is toxic. The most commonly encountered form of heated fog machine is the pump machine. Very basic models of this type of machine consist of a fluid reservoir, an electric pump to move

title: Solar thermal collector

text: they completely drain using gravity before freezing is expected, so that they do not crack. Many metal collectors are installed as part of a sealed heat exchanger system. Rather than having potable water flow directly through the collectors, a mixture of water and antifreeze such as propylene glycol is used. A heat exchange fluid protects against freeze damage down to a locally determined risk temperature that depends on the proportion of propylene glycol in the mixture. The use of glycol lowers the water's heat carrying capacity marginally, while the addition of an extra heat exchanger may lower system performance at

title: Internal combustion engine cooling

text: such as antifreeze and rust inhibitors. The industry term for the antifreeze mixture is "engine coolant". Some antifreezes use no water at all, instead using a liquid with different properties, such as propylene glycol or a combination of propylene glycol and ethylene glycol. Most "air-cooled" engines use some liquid oil cooling, to maintain acceptable temperatures for both critical engine parts and the oil itself. Most "liquid-cooled" engines use some air cooling, with the intake stroke of air cooling the combustion chamber. An exception is Wankel engines, where some parts of the combustion chamber are never cooled by intake, requiring extra

title: Ethylene glycol

text: process was commercialized and offered for licenses. Ethylene glycol is primarily used in antifreeze formulations (50%) and as a raw material in the manufacture of polyesters such as polyethylene terephthalate (PET) (40%). The major use of ethylene glycol is as a medium for convective heat transfer in, for example, automobiles and liquid-cooled computers. Ethylene glycol is also commonly used in chilled-water air-conditioning systems that place either the chiller or air handlers outside, or systems that must cool below the freezing temperature of water. In geothermal heating/cooling systems, ethylene glycol is the fluid that transports heat through the use of a

title: Propylene carbonate

text: frequently used as a high-permittivity component of electrolytes in lithium batteries, usually together with a low-viscosity solvent (e.g. dimethoxyethane). Its high polarity allows it to create an effective solvation shell around lithium ions, thereby creating a conductive electrolyte. However, it is not used in lithium-ion batteries due to its destructive effect on graphite. Propylene carbonate can also be found in some adhesives, paint strippers, and in cosmetics. It is also used as plasticizer. Propylene carbonate is also used as a solvent for removal of CO from natural gas and synthesis gas where HS is not also present. This use was

title: Ethylene glycol poisoning

text: ethylene glycol-based coolants, and only produces lactic acid in an animal's body, as their muscles do when exercised. When using antifreeze products containing ethylene glycol, recommended safety measures include: The most important initial treatment for ethylene glycol poisoning is stabilizing the patient. As ethylene glycol is rapidly absorbed, gastric decontamination is unlikely to be of benefit unless it is performed within 60 minutes of ingestion. Traditionally, gastric lavage or nasogastric aspiration of gastric contents are the most common methods employed in ethylene glycol poisoning. The usefulness of gastric lavage has, however, been questioned, and it is now no longer used

title: Propylene glycol

text: and pharmacology, the number is E490. Propylene glycol is also present in propylene glycol alginate which known as E405. The compound is sometimes called (alpha) α-propylene glycol to distinguish it from the isomer propane-1,3-diol, known as (beta) β-propylene glycol. Propylene glycol is a clear, colorless and hygroscopic liquid. Propylene glycol contains an asymmetrical carbon atom, so it exists in two enantiomers. The commercial product is a racemic mixture. Pure optical isomers can be obtained by hydration of optically pure propylene oxide. The freezing point of water is depressed when mixed with propylene glycol, owing to the effects of dissolution of

title: Propylene glycol

text: 1.5% of dipropylene glycol and small amounts of other polypropylene glycols. Further purification produces finished industrial grade or USP/JP/EP/BP grade propylene glycol that is typically 99.5% or greater. Propylene glycol can also be converted from glycerol, a biodiesel byproduct. This starting material is usually reserved for industrial use because of the noticeable odor and taste that accompanies the final product. "S-"Propanediol may be synthesized from -mannitol, through the following scheme: Forty-five percent of propylene glycol produced is used as chemical feedstock for the production of unsaturated polyester resins. In this regard, propylene glycol reacts with a mixture of unsaturated maleic

title: Propylene glycol dinitrate

text: at 0.05 ppm (0.3 mg/m) over an eight-hour workday, for dermal exposures. Propylene glycol dinitrate Propylene glycol dinitrate (PGDN, 1,2-propylene glycol dinitrate, or 1,2-propanediol dinitrate) is an organic chemical, an ester of nitric acid and propylene glycol. It is structurally similar to nitroglycerin, except that it has one fewer nitrate group. It is a characteristically and unpleasantly smelling colorless liquid, which decomposes at 121 °C, below its boiling point. It is flammable and explosive. It is shock-sensitive and burns with a clean flame producing water vapor, carbon monoxide, and nitrogen gas. The principal current use of propylene glycol dinitrate is

title: Propylene glycol dinitrate

text: Propylene glycol dinitrate Propylene glycol dinitrate (PGDN, 1,2-propylene glycol dinitrate, or 1,2-propanediol dinitrate) is an organic chemical, an ester of nitric acid and propylene glycol. It is structurally similar to nitroglycerin, except that it has one fewer nitrate group. It is a characteristically and unpleasantly smelling colorless liquid, which decomposes at 121 °C, below its boiling point. It is flammable and explosive. It is shock-sensitive and burns with a clean flame producing water vapor, carbon monoxide, and nitrogen gas. The principal current use of propylene glycol dinitrate is as a propellant in Otto Fuel II, together with 2-nitrodiphenylamine and dibutyl

title: Propylene glycol

text: glycol is minimally irritating to the eye, producing slight transient conjunctivitis; the eye recovers after the exposure is removed. Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists could be irritating to some individuals. It is therefore recommended that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as simulated fogs for theatrical productions, or

title: Propylene glycol

text: anhydride and isophthalic acid to give a copolymer. This partially unsaturated polymer undergoes further crosslinking to yield thermoset plastics. Related to this application, propylene glycol reacts with propylene oxide to give oligomers and polymers that are used to produce polyurethanes. Propylene glycol is used in waterbased acrylic architectural paints to extend dry time which it accomplishes by preventing the surface from drying due to its slower evaporation rate compared to water. Propylene glycol is used as a humectant (E1520), solvent, and preservative in food and for tobacco products. It is also one of the major ingredients (<1–92%), along with Vegetable

title: Propylene glycol

text: T abnormalities on the ECG, arrhythmia, cardiac arrest, serum hyperosmolality, lactic acidosis, and haemolysis". A high percentage (12% to 42%) of directly-injected propylene glycol is eliminated or secreted in urine unaltered depending on dosage, with the remainder appearing in its glucuronide-form. The speed of renal filtration decreases as dosage increases, which may be due to propylene glycol's mild anesthetic / CNS-depressant -properties as an alcohol. In one case, intravenous administration of propylene glycol-suspended nitroglycerin to an elderly man may have induced coma and acidosis. Propylene glycol is an approved food additive for dog and sugar glider food under the category

title: Propylene glycol

text: vitamin D balances. Therefore, propylene glycol allergy is more common in those countries. Propylene glycol is known to exert high levels of biochemical oxygen demand (BOD) during degradation in surface waters. This process can adversely affect aquatic life by consuming oxygen needed by aquatic organisms for survival. Large quantities of dissolved oxygen (DO) in the water column are consumed when microbial populations decompose propylene glycol. Sufficient dissolved oxygen levels in surface waters are critical for the survival of fish, macroinvertebrates, and other aquatic organisms. If oxygen concentrations drop below a minimum level, organisms emigrate, if able and possible, to areas

title: Propylene glycol

text: disorders in children, including asthma, hay fever, eczema, and allergies, with increased risk ranging from 50% to 180%. This concentration has been linked to use of water-based paints and water-based system cleansers. However, the study authors write that glycol ethers and not propylene glycol are the likely culprit. Propylene glycol does not cause sensitization, and it shows no evidence of being a carcinogen or of being genotoxic. Adverse responses to intravenous administration of drugs that use propylene glycol as an excipient have been seen in a number of people, particularly with large dosages. Responses may include "hypotension, bradycardia... QRS and

title: Propylene glycol

text: used to winterize the plumbing systems in vacant structures. The eutectic composition/temperature is 60:40 propylene glycol:water/-60 °C. The −50 °F/−45 °C commercial product is, however, water rich; a typical formulation is 40:60. Propylene glycol is used in veterinary medicine as an oral treatment for hyperketonaemia in ruminants. Glucose, which can be used in non-ruminants for this purpose, is not effective due to its consumption by the resident microbes of the rumen. Propylene glycol is partially metabolized in the rumen to propionate which can be used as an energy source. The remainder is absorbed into the bloodstream and used by the

title: Propylene glycol

text: provided with feed containing as much as 5% PG over a period of 2 years, and showed no apparent ill effects; no data on offspring were offered. Because of its low chronic oral toxicity, propylene glycol was classified by the U. S. Food and Drug Administration as "generally recognized as safe" (GRAS) for use as a direct food additive, including frozen foods such as ice cream and frozen desserts. The GRAS designation is specific to its use in food, and does not apply to other uses. Prolonged contact with propylene glycol (E490) is essentially non-irritating to the skin. Undiluted propylene

title: Propylene glycol

text: with higher oxygen levels or eventually die. This effect can drastically reduce the amount of usable aquatic habitat. Reductions in DO levels can reduce or eliminate bottom feeder populations, create conditions that favor a change in a community’s species profile, or alter critical food-web interactions. Propylene glycol Propylene glycol (IUPAC name: propane-1,2-diol) is a synthetic organic compound with the chemical formula CHO. It is a viscous, colorless liquid which is nearly odorless but possesses a faintly sweet taste. Chemically it is classed as a diol and is miscible with a broad range of solvents, including water, acetone, and chloroform. It

title: Propylene glycol

text: of animal feed and is generally recognized as safe for dogs, with an of 9 mL/kg. The LD is higher for most laboratory animals (20 mL/kg). However, it is prohibited for use in food for cats due to links to Heinz body anemia. Individuals who cannot tolerate propylene glycol experience inflamed dry skin in the facial area, or small red dots on the body. Investigators believe that the incidence of allergic contact dermatitis to propylene glycol may be greater than 2% in patients with eczema or fungal infections, which are very common in countries with lesser sun exposure and lower-than-normal

title: Propylene glycol

text: liver for gluconeogenesis. The acute oral toxicity of propylene glycol (E1520) is very low, and large quantities are required to cause perceptible health damage in humans; propylene glycol is metabolized in the human body into pyruvic acid (a normal part of the glucose-metabolism process, readily converted to energy), acetic acid (handled by ethanol-metabolism), lactic acid (a normal acid generally abundant during digestion), and propionaldehyde (a potentially hazardous substance). According to the Dow Chemical Company, The LD (Lethal Dose that kills in 50% of tests,) for rats is 20 g/kg (rat/oral). Serious toxicity generally occurs at plasma concentrations over 4 g/L,

title: Propylene glycol

text: which requires extremely high intake over a relatively short period of time, or when used as a vehicle for drugs or vitamins given intravenously or orally. It would be nearly impossible to reach toxic levels by consuming foods or supplements, which contain at most 1 g/kg of PG, except for alcoholic beverages in the US which are allowed 5 percent = 50g/kg. Cases of propylene glycol poisoning are usually related to either inappropriate intravenous administration or accidental ingestion of large quantities by children. The potential for long-term oral toxicity is also low. In one study, in 1972, 12 rats were

title: Propylene glycol dinitrate

text: sebacate. Otto Fuel II is used in some torpedoes as a propellant. Nitrates of polyhydric alcohols, of which propylene glycol dinitrate is an example, have been used in medicine for the treatment of angina pectoris, and as explosives since the mid-nineteenth century. PGDN affects blood pressure, causes respiratory toxicity, damages liver and kidneys, distorts vision, causes methoglobinuria, and can cause headache and lack of coordination. It may be absorbed through skin. Its primary toxicity mechanism is methemoglobinemia. It may cause permanent nerve damage. For occupational exposures, the National Institute for Occupational Safety and Health has set a recommended exposure limit

title: Propylene oxide

text: only water was a side product. In practice, ring-opened derivatives of PO are generated. Like other epoxides, PO undergoes ring-opening reactions. With water, propylene glycol is produced. With alcohols, reactions, called hydroxylpropylation, analogous to ethoxylation occur. Grignard reagents add to propylene oxide to give secondary alcohols. Some other reactions of propylene oxide include: Between 60 and 70% of all propylene oxide is converted to polyether polyols by the process called alkoxylation. These polyols are building blocks in the production of polyurethane plastics. About 20% of propylene oxide is hydrolyzed into propylene glycol, via a process which is accelerated by acid

title: Polypropylene glycol

text: Polypropylene glycol Polypropylene glycol or polypropylene oxide is the polymer of propylene glycol. Chemically it is a polyether. The term polypropylene glycol or PPG is reserved for low to medium range molar mass polymer when the nature of the end-group, which is usually a hydroxyl group, still matters. The term "oxide" is used for high molar mass polymer when end-groups no longer affect polymer properties. In 2003, 60% of the annual production of propylene oxide of 6.6×10 tonnes was converted into the polymer. Polypropylene glycol is produced by ring-opening polymerization of propylene oxide. The initiator is an alcohol and the

title: Propylene oxide

text: or base catalysis. Other major products are polypropylene glycol, propylene glycol ethers, and propylene carbonate. The United States Food and Drug Administration has approved the use of propylene oxide to pasteurize raw almonds beginning on September 1, 2007, in response to two incidents of contamination by "Salmonella" in commercial orchards, one incident occurring in Canada and one in the United States. Pistachio nuts can also be subjected to propylene oxide to control "Salmonella". Propylene oxide is commonly used in the preparation of biological samples for electron microscopy, to remove residual ethanol previously used for dehydration. In a typical procedure, the

title: Propylene carbonate

text: fed propylene carbonate, exposed to the vapor, or exposed to the undiluted liquid. In the US, propylene carbonate is not regulated as a volatile organic compound (VOC) because it does not contribute significantly to the formation of smog and because its vapor is not known or suspected to cause cancer or other toxic effects. Propylene carbonate Propylene carbonate (often abbreviated PC) is an organic compound with the formula CHCHOCO. It is a carbonate ester derived from propylene glycol. This colorless and odorless liquid is useful as a polar, aprotic solvent. Propylene carbonate is chiral but is used exclusively as the

title: Propylene carbonate

text: Propylene carbonate Propylene carbonate (often abbreviated PC) is an organic compound with the formula CHCHOCO. It is a carbonate ester derived from propylene glycol. This colorless and odorless liquid is useful as a polar, aprotic solvent. Propylene carbonate is chiral but is used exclusively as the racemic mixture. Although many organic carbonates are produced using phosgene, propylene and ethylene carbonates are exceptions. They are mainly prepared by the carbonation of the epoxides (epoxypropane, or propylene oxide here): The process is particularly attractive since the production of these epoxides consumes carbon dioxide. Thus this reaction is a good example of a

title: Polypropylene glycol

text: catalyst a base, usually potassium hydroxide. When the initiator is ethylene glycol or water the polymer is linear. With a multifunctional initiator like glycerine, pentaerythritol or sorbitol the polymer branches out. Conventional polymerization of propylene oxide results in an atactic polymer. The isotactic polymer can be produced from optically active propylene oxide, but at a high cost. A salen cobalt catalyst was reported in 2005 to provide isotactic polymerization of the prochiral propylene oxide PPG has many properties in common with polyethylene glycol. The polymer is a liquid at room temperature. Solubility in water decreases rapidly with increasing molar mass.

title: Propylene carbonate

text: green process. The corresponding reaction of 1,2-propanediol with phosgene is complex, yielding not only propylene carbonate but also oligomeric products. Propylene carbonate can also be synthesized from urea and propylene glycol over zinc acetate. Propylene carbonate is used as a polar, aprotic solvent. It has a high molecular dipole moment (4.9 D), considerably higher than those of acetone (2.91 D) and ethyl acetate (1.78 D). It is possible, for example, to obtain potassium, sodium, and other alkali metals by electrolysis of their chlorides and other salts dissolved in propylene carbonate. Due to its high dielectric constant of 64, it is

title: Glycol ethers

text: occupational exposure to glycol ethers is related to low motile sperm count, a finding disputed by the chemical industry. Glycol ethers Glycol ethers are a group of solvents based on alkyl ethers of ethylene glycol or propylene glycol commonly used in paints and cleaners. These solvents typically have a higher boiling point, together with the favorable solvent properties of lower-molecular weight ethers and alcohols. The word "Cellosolve" was registered in 1924 as a United States trademark by Carbide & Carbon Chemicals Corp. (later named Union Carbide Corp.) for "Solvents for Gums, Resins, Cellulose Esters, and the Like",; the first one

title: Glycol ethers

text: Glycol ethers Glycol ethers are a group of solvents based on alkyl ethers of ethylene glycol or propylene glycol commonly used in paints and cleaners. These solvents typically have a higher boiling point, together with the favorable solvent properties of lower-molecular weight ethers and alcohols. The word "Cellosolve" was registered in 1924 as a United States trademark by Carbide & Carbon Chemicals Corp. (later named Union Carbide Corp.) for "Solvents for Gums, Resins, Cellulose Esters, and the Like",; the first one was ethyl cellosolve (ethylene glycol monoethyl ether), with the name now generic for glycol ethers. Glycol ethers are either

title: Safety of electronic cigarettes

text: glycol has not been studied, and is unknown, as well as the effects of inhaled glycerin. Acute exposure to propylene glycol may cause irritation to the eyes and respiratory tract, however there is speculation that the risk from the inhalation of propylene glycol and glycerin is probably low, despite lack of evidence that either ingredient is safe. Some research states that long-term inhalation of propylene glycol emissions may cause respiratory irritation and raise the likelihood to develop asthma, especially in children. To lessen the risks, most e-cigarettes companies began to use water and glycerin as replacement for propylene glycol, although

title: Diethylene glycol

text: patients started to present anuria, acidic breathing, hepatomegaly, and unresponsiveness. Patients were treated with fluid hydration and correction of acidosis, but some were not able to survive. Postmortem examination revealed damage in the kidneys and liver, and laboratory testing found DEG instead of propylene glycol in the sedatives. Patients being treated for burns developed sudden anuric renal failure. Further investigation revealed all patients were treated with topical silver sulfadiazine ointment that contained 7 g/kg of DEG. This event caused the death of five patients. During the month of July 1985, Austrian wines were found to contain up to 1,000 parts

title: Electronic cigarette aerosol and liquid

text: The main ingredients are propylene glycol, glycerine, and flavorings; and most often, nicotine in liquid form. The liquid typically contains 95% propylene glycol and glycerin, and the remaining 5% being flavorings and nicotine. E-liquid can be made with or without nicotine, with >90% of e-liquids containing some level of nicotine. The most regularly used base carrier chemical is propylene glycol with or without glycerin. E-liquid containing glycerin and water made without propylene glycol are also sold. Unless clearly stated, it is uncertain whether the nicotine used in e-liquid is manufactured using a United States Pharmacopeia (USP) grade nicotine, a tobacco

title: Propylene oxide

text: Propylene oxide Propylene oxide is an organic compound with the molecular formula CHCHCHO. This colourless volatile liquid with an odour resembling ether, is produced on a large scale industrially. Its major application is its use for the production of polyether polyols for use in making polyurethane plastics. It is a chiral epoxide, although it is commonly used as a racemic mixture. This compound is sometimes called 1,2-propylene oxide to distinguish it from its isomer 1,3-propylene oxide, better known as oxetane. Industrial production of propylene oxide starts from propylene. Two general approaches are employed, one involving hydrochlorination and the other involving

title: Safety of electronic cigarettes

text: consumers so they really don’t know what they are ingesting, or how much." A 2014 review found "Various chemical substances and ultrafine particles known to be toxic, carcinogenic and/or to cause respiratory and heart distress have been identified in e-cigarette aerosols, cartridges, refill liquids and environmental emissions." Few of the methods used to analyze the chemistry of e-cigarettes in the studies the review evaluated were validated. The primary base ingredients of the liquid solution is propylene glycol and glycerin, of which about 20% to 27% of propylene glycol and glycerin-based liquid particles are inhaled. The long-term effects of inhaled propylene

title: Antifreeze

text: cream, frozen custard, salad dressings, and baked goods, and it is commonly used as the main ingredient in the "e-liquid" used in electronic cigarettes. Propylene glycol oxidizes when exposed to air and heat, forming lactic acid. If not properly inhibited, this fluid can be very corrosive, so pH buffering agents such as dipotassium phosphate and potassium bicarbonate are often added to propylene glycol, to prevent acidic corrosion of metal components. Pre-inhibited propylene glycol solutions can also be used instead of pure propylene glycol to prevent corrosion. Besides cooling system corrosion, biological fouling also occurs. Once bacterial slime starts to grow,

title: Ethylene glycol poisoning

text: the U.S., airports are required to obtain stormwater discharge permits and ensure that wastes from deicing operations are properly collected and treated. Large new airports may be required to collect 60 percent of aircraft deicing fluid after deicing. Airports that discharge the collected aircraft deicing fluid directly to waters of the U.S. must also meet numeric discharge requirements for chemical oxygen demand. A report in 2000 stated that ethylene glycol was becoming less popular for aircraft deicing in the U.S., due to its reporting requirements and adverse environmental impacts (p. 213), and noted a shift to the use of propylene

title: Electronic cigarette aerosol and liquid

text: UK on the nicotine content, meaning the nicotine strength of any e-liquid cannot exceed 20 mg/mL (2.0%). Electronic cigarette aerosol and liquid E-liquid is the mixture used in electronic cigarettes. The main ingredients in the e-liquid usually are propylene glycol, glycerin, nicotine, and flavorings. However, there are e-liquids sold without propylene glycol, nicotine, or flavors. The liquid typically contains 95% propylene glycol and glycerin. Propylene glycol and glycerine are used to produce the vapor while the flavoring provides the taste and aroma. The flavorings may be natural or artificial. About 8,000 flavors exist as of 2014. There are many e-liquids

title: Electronic cigarette aerosol and liquid

text: Electronic cigarette aerosol and liquid E-liquid is the mixture used in electronic cigarettes. The main ingredients in the e-liquid usually are propylene glycol, glycerin, nicotine, and flavorings. However, there are e-liquids sold without propylene glycol, nicotine, or flavors. The liquid typically contains 95% propylene glycol and glycerin. Propylene glycol and glycerine are used to produce the vapor while the flavoring provides the taste and aroma. The flavorings may be natural or artificial. About 8,000 flavors exist as of 2014. There are many e-liquids manufacturers in the USA and worldwide. While there are currently no US Food and Drug Administration (FDA)

title: Antifreeze

text: the corrosion rate of the system increases. Maintenance of systems using glycol solution includes regular monitoring of freeze protection, pH, specific gravity, inhibitor level, color, and biological contamination. Propylene glycol should be replaced when it turns a reddish color. When an aqueous solution of propylene glycol in a cooling or heating system develops a reddish or black color, this indicates that iron in the system is corroding significantly. In the absence of inhibitors, propylene glycol can react with oxygen and metal ions, generating various compounds including organic acids (e.g., formic, oxalic, acetic). These acids accelerate the corrosion of metals in

title: Lorazepam

text: propylene glycol with 2.0% benzyl alcohol as preservative. Lorazepam injectable solution is administered either by deep intramuscular injection or by intravenous injection. The injectable solution comes in 1 ml ampoules containing 2 or 4 mg of lorazepam. The solvents used are polyethylene glycol 400 and propylene glycol. As a preservative, the injectable solution contains benzyl alcohol. Toxicity from propylene glycol has been reported in the case of a patient receiving a continuous lorazepam infusion. Intravenous injections should be given slowly and patients closely monitored for side effects, such as respiratory depression, hypotension, or loss of airway control. Peak effects roughly

title: Propylene oxide

text: sample is first immersed in a mixture of equal volumes of ethanol and propylene oxide for 5 minutes, and then four times in pure oxide, 10 minutes each. It is a probable human carcinogen, and is included into the List of IARC Group 2B carcinogens. In 2016 it was reported that propylene oxide was detected in Sagittarius B2, a cloud of gas in the Milky Way weighing three million solar masses. It is the first chiral molecule to be detected in space. Propylene oxide Propylene oxide is an organic compound with the molecular formula CHCHCHO. This colourless volatile liquid with

title: Environmental impact of aviation

text: be carried via stormwater runoff to nearby streams, rivers or coastal waters. Airlines use deicing fluids based on ethylene glycol or propylene glycol as the active ingredient. Ethylene glycol and propylene glycol are known to exert high levels of biochemical oxygen demand (BOD) during degradation in surface waters. This process can adversely affect aquatic life by consuming oxygen needed by aquatic organisms for survival. Large quantities of dissolved oxygen (DO) in the water column are consumed when microbial populations decompose propylene glycol. Sufficient dissolved oxygen levels in surface waters are critical for the survival of fish, macroinvertebrates, and other aquatic

title: Propylene oxide

text: oxidation. In 2005, about half of the world production was through chlorohydrin technology and one half via oxidation routes. The latter approach is growing in importance. The traditional route proceeds via the conversion of propylene to propylene chlorohydrin, which is produced according to the following simplified scheme: The mixture of 1-chloro-2-propanol and 2-chloro-1-propanol, which is then dehydrochlorinated. For example: Lime (Ca(OH)) is often used to absorb the HCl. The other general route to propylene oxide involves oxidation of propylene with an organic peroxide. The reaction follows this stoichiometry: The process is practiced with four hydroperoxides: In principle, this process produces

title: Glycol dehydration

text: Glycol dehydration Glycol dehydration is a liquid desiccant system for the removal of water from natural gas and natural gas liquids (NGL). It is the most common and economical means of water removal from these streams. Glycols typically seen in industry include triethylene glycol (TEG), diethylene glycol (DEG), ethylene glycol (MEG), and tetraethylene glycol (TREG). TEG is the most commonly used glycol in industry. The purpose of a glycol dehydration unit is to remove water from natural gas and natural gas liquids. When produced from a reservoir, natural gas usually contains a large amount of water and is typically completely

title: Glycol dehydration

text: the reboiler are partially condensed and drawn out separately from the bulk liquid. Glycol dehydration Glycol dehydration is a liquid desiccant system for the removal of water from natural gas and natural gas liquids (NGL). It is the most common and economical means of water removal from these streams. Glycols typically seen in industry include triethylene glycol (TEG), diethylene glycol (DEG), ethylene glycol (MEG), and tetraethylene glycol (TREG). TEG is the most commonly used glycol in industry. The purpose of a glycol dehydration unit is to remove water from natural gas and natural gas liquids. When produced from a reservoir,

title: Diethylene glycol

text: bond. "Diethylene glycol is derived as a co-product with ethylene glycol (MEG) and triethylene glycol. The industry generally operates to maximize MEG production. Ethylene glycol is by far the largest volume of the glycol products in a variety of applications. Availability of DEG will depend on demand for derivatives of the primary product, ethylene glycol, rather than on DEG market requirements." Diethylene glycol is one of several glycols derived from ethylene oxide. Glycols related to and coproduced with diethylene glycol and have the formula HOCHCH(OCHCH)OH are: These compounds are all hydrophilic, more so than most diols, by virtue of the

title: Safety of electronic cigarettes

text: by children, particularly youngsters, long after they were used. E-liquid is the mixture used in vapor products such as electronic cigarettes. The main ingredients in the e-liquid usually are propylene glycol, glycerin, nicotine, and flavorings. However, there are e-liquids sold without propylene glycol, nicotine, or flavors. The liquid typically contains 95% propylene glycol and glycerin. The flavorings may be natural or artificial. About 8,000 flavors exist as of 2014. There are many e-liquids manufacturers in the USA and worldwide. While there are currently no US Food and Drug Administration (FDA) manufacturing standards for e-liquid, the FDA has proposed regulations that

title: Propylene carbonate

text: developed by El Paso Natural Gas Company and Fluor Corporation in the 1950s for use at the Terrell County Gas Plant in West Texas, now owned by Occidental Petroleum. Propylene carbonate product may be converted to other carbonate esters by transesterification as well (see Carbonate ester#Carbonate transesterification). In electrospray ionization mass spectrometry, propylene carbonate is doped into low surface tension solutions to increase analyte charging. Clinical studies indicate that propylene carbonate does not cause skin irritation or sensitization when used in cosmetic preparations, whereas moderate skin irritation is observed when used undiluted. No significant toxic effects were observed in rats

title: Ethylene glycol

text: purity of glycol used for hydrate suppression (monoethylene glycol) is typically around 80%, whereas the purity of glycol used for dehydration (triethylene glycol) is typically 95 to more than 99%. Moreover, the injection rate for hydrate suppression is much lower than the circulation rate in a glycol dehydration tower. Minor uses of ethylene glycol include the manufacture of capacitors, as a chemical intermediate in the manufacture of 1,4-dioxane, as an additive to prevent corrosion in liquid cooling systems for personal computers, and inside the lens devices of cathode-ray tube type of rear projection televisions. Ethylene glycol is also used in

title: Deicing fluid

text: Deicing fluid Ground deicing of aircraft is commonly performed in both commercial and general aviation. The fluids used in this operation are called deicing or anti-icing fluids. The abbreviations ADF (Aircraft Deicing Fluid) or AAF (Aircraft Anti-icing Fluid) are commonly used. Deicing fluids come in a variety of types, and are typically composed of ethylene glycol (EG) or propylene glycol (PG), along with other ingredients such as thickening agents, surfactants (wetting agents), corrosion inhibitors, and colored, UV-sensitive dye. Propylene glycol-based fluid is more common due to the fact that it is less toxic than ethylene glycol. SAE International (formerly known

title: Ethylene glycol

text: volatile liquids. In the plastic industry, ethylene glycol is an important precursor to polyester fibers and resins. Polyethylene terephthalate, used to make plastic bottles for soft drinks, is prepared from ethylene glycol. Ethylene glycol is used in the natural gas industry to remove water vapor from natural gas before further processing, in much the same manner as triethylene glycol (TEG). Because of its high boiling point and affinity for water, ethylene glycol is a useful desiccant. Ethylene glycol is widely used to inhibit the formation of natural gas clathrates (hydrates) in long multiphase pipelines that convey natural gas from remote

title: Glycol dehydration

text: top of an absorber (also known as a "glycol contactor") where it is contacted with the wet natural gas stream. The glycol removes water from the natural gas by physical absorption and is carried out the bottom of the column. Upon exiting the absorber the glycol stream is often referred to as "rich glycol". The dry natural gas leaves the top of the absorption column and is fed either to a pipeline system or to a gas plant. Glycol absorbers can be either tray columns or packed columns. After leaving the absorber, the rich glycol is fed to a flash

title: Acetic acid

text: Tishchenko reaction. In addition, ether acetates are used as solvents for nitrocellulose, acrylic lacquers, varnish removers, and wood stains. First, glycol monoethers are produced from ethylene oxide or propylene oxide with alcohol, which are then esterified with acetic acid. The three major products are ethylene glycol monoethyl ether acetate (EEA), ethylene glycol monobutyl ether acetate (EBA), and propylene glycol monomethyl ether acetate (PMA, more commonly known as PGMEA in semiconductor manufacturing processes, where it is used as a resist solvent). This application consumes about 15% to 20% of worldwide acetic acid. Ether acetates, for example EEA, have been shown to

title: Dow Chemical Company

text: control and the food industry. Major products include ethylene glycol, caustic soda, chlorine, and vinyl chloride monomer (VCM, for making PVC). Ethylene oxide and propylene oxide and the derived alcohols ethylene glycol and propylene glycol are major feedstocks for the manufacture of plastics such as polyurethane and PET. The Hydrocarbons and Energy operating segment (13 percent of sales) oversees energy management at Dow. Fuels and oil-based raw materials are also procured. Major feedstocks for Dow are provided by this group, including ethylene, propylene, 1,3-butadiene, benzene and styrene. Dow was founded in 1897 by chemist Herbert Henry Dow, who invented a

title: Glycol cleavage

text: dihydroxylation, the KMnO can then easily cleave the glycol to give aldehydes or ketones. The aldehydes will react further with (KMnO), being oxidized to become carboxylic acids. Controlling the temperature and concentration of the reagent can keep the reaction from continuing past the formation of the glycol. Glycol cleavage Glycol cleavage is a specific type of organic chemistry oxidation. The carbon–carbon bond in a vicinal diol (glycol) is cleaved and instead the two oxygen atoms become double-bonded to their respective carbon atoms. Depending on the substitution pattern in the diol, these carbonyls can be either ketones or aldehydes. Glycol cleavage

title: Thymine glycol

text: Thymine glycol Thymine glycol (5,6-dihydroxy-5,6-dihydrothymine) is one of the principal DNA lesions that can be induced by oxidation and ionizing radiation. The rate at which oxidative reactions generate thymine glycol and thymidine glycol in the DNA of humans is estimated to be about 300 per cell per day. Oxidized DNA bases that are excised by DNA repair processes are excreted in urine. On a body weight basis, mice excrete 18 times more thymine glycol plus thymidine glycol than humans, and monkeys four times more than humans. It was proposed that rate of occurrence of oxidative DNA damages correlates with metabolic

title: Fluorinated ethylene propylene

text: resin away from the FEP film. The plastic is useful as a sample holder material in microscopy applications as its refractive index is close to that of water at visible wavelengths , (FEP: 1.344, water: 1.335). This minimizes the blur due to optical aberrations when the light traverses the sample container. Fluorinated ethylene propylene Fluorinated ethylene propylene (FEP) is a copolymer of hexafluoropropylene and tetrafluoroethylene. It differs from the polytetrafluoroethylene (PTFE) resins in that it is melt-processable using conventional injection molding and screw extrusion techniques. Fluorinated ethylene propylene was invented by DuPont and is sold under the brandname Teflon FEP.

title: Fluorinated ethylene propylene

text: Fluorinated ethylene propylene Fluorinated ethylene propylene (FEP) is a copolymer of hexafluoropropylene and tetrafluoroethylene. It differs from the polytetrafluoroethylene (PTFE) resins in that it is melt-processable using conventional injection molding and screw extrusion techniques. Fluorinated ethylene propylene was invented by DuPont and is sold under the brandname Teflon FEP. Other brandnames are Neoflon FEP from Daikin or Dyneon FEP from Dyneon/3M. FEP is very similar in composition to the fluoropolymers PTFE (polytetrafluoroethylene) and PFA (perfluoroalkoxy polymer resin). FEP and PFA both share PTFE's useful properties of low friction and non-reactivity, but are more easily formable. FEP is softer than PTFE

title: Glycol dehydration

text: vessel where hydrocarbon vapors are removed and any liquid hydrocarbons are skimmed from the glycol. This step is necessary as the absorber is typically operated at high pressure and the pressure must be reduced before the regeneration step. Due to the composition of the rich glycol, a vapor phase having a high hydrocarbon content will form when the pressure is lowered. After leaving the flash vessel, the rich glycol is heated in a cross-exchanger and fed to the stripper (also known as a regenerator). The glycol stripper consists of a column, an overhead condenser, and a reboiler. The glycol is

title: Ethylene glycol

text: gas fields to a gas processing facility. Ethylene glycol can be recovered from the natural gas and reused as an inhibitor after purification treatment that removes water and inorganic salts. Natural gas is dehydrated by ethylene glycol. In this application, ethylene glycol flows down from the top of a tower and meets a rising mixture of water vapor and hydrocarbon gases. Dry gas exits from the top of the tower. The glycol and water are separated, and the glycol recycled. Instead of removing water, ethylene glycol can also be used to depress the temperature at which hydrates are formed. The

title: Diethylene glycol

text: suggest this is the LD. Because of its adverse effects on humans, diethylene glycol is not allowed for use in food and drugs. The U.S. Code of Federal Regulations allows no more than 0.2% of diethylene glycol in polyethylene glycol when the latter is used as a food additive. The Australian government does not allow DEG as a food additive; it is only allowed at less than 0.25% w/w of DEG as an impurity of polyethylene glycol (PEG) even in toothpaste. Diethylene glycol has moderate acute toxicity in animal experiments. The LD for small mammals has been tested at between

title: Ethylene glycol

text: occur at neutral pH under elevated temperatures. The highest yields of ethylene glycol occur at acidic or neutral pH with a large excess of water. Under these conditions, ethylene glycol yields of 90% can be achieved. The major byproducts are the oligomers diethylene glycol, triethylene glycol, and tetraethylene glycol. The separation of these oligomers and water is energy-intensive. About 6.7 million tonnes are produced annually. A higher selectivity is achieved by use of Shell's OMEGA process. In the OMEGA process, the ethylene oxide is first converted with carbon dioxide () to ethylene carbonate. This ring is then hydrolyzed with a

title: Glycol dehydration

text: thermally regenerated to remove excess water and regain the high glycol purity. The hot, lean glycol is cooled by cross-exchange with rich glycol entering the stripper. It is then fed to a lean pump where its pressure is elevated to that of the glycol absorber. The lean solvent is cooled again with a trim cooler before being fed back into the absorber. This trim cooler can either be a cross-exchanger with the dry gas leaving the absorber or an air-cooled exchanger. Most glycol units are fairly uniform except for the regeneration step. Several methods are used to enhance the stripping

title: Solar air conditioning

text: conductivity to the earth. In the past the fluid of choice was a 50/50 mixture of propylene glycol because it is non-toxic unlike ethylene glycol (which is used in car radiators). Propylene glycol is viscous, and would eventually gum up some parts in the loop(s), so it has fallen out of favor. Today, the most common transfer agent is a mixture of water and ethyl alcohol (ethanol). Ambient earth temperature is much lower than peak summer air temperature, and much higher than the lowest extreme winter air temperature. Water is 25 times more thermally conductive than air, so it is

title: Ethylene glycol

text: about 10 days and in water or soil in a few weeks. It enters the environment through the dispersal of ethylene glycol-containing products, especially at airports, where it is used in deicing agents for runways and aeroplanes. While prolonged low doses of ethylene glycol show no toxicity, at near lethal doses (≥ 1000 mg/kg per day) ethylene glycol acts as a teratogen. "Based on a rather extensive database, it induces [skeletal variations and malformations] in rats and mice by all routes of exposure." This molecule has been observed in outer space. Ethylene glycol Ethylene glycol (IUPAC name: ethane-1,2-diol) is an

title: Manali Petrochemical

text: the technology of Enichem of Italy for the PO and PG and Press Industrial for manufacture of Polyol.MPL markets its Polyols with isocyanates sourced indigenously as well as imported from Japan and China and the pre-polymers produced at MPL in meeting the demand of polyurethane industry in India. Manali Petrochemical Manali Petrochemical Ltd. (MPL) is a petrochemical company based in India. It markets propylene glycol and polyols It is based in Chennai. Manali Petrochemical annually produces 27000 metric tonnes of propylene oxide, 14,000 metric tonnes of propylene glycol and 15,000 metric tonnes of polyether polyol and system polyol. Manali Petrochemical

title: Manali Petrochemical

text: Manali Petrochemical Manali Petrochemical Ltd. (MPL) is a petrochemical company based in India. It markets propylene glycol and polyols It is based in Chennai. Manali Petrochemical annually produces 27000 metric tonnes of propylene oxide, 14,000 metric tonnes of propylene glycol and 15,000 metric tonnes of polyether polyol and system polyol. Manali Petrochemical Ltd Plant-I (originally built by SPIC) set up with the technology of Atochem for manufacture of PO and PG and that of Arco for manufacture of Polyuol acquired through Technip, France. Manali Petrochemical Ltd Plant-II (originally joint venture of UB and TIDCO) was merged with MPL later utilizes

title: Diol

text: Diol A diol is a chemical compound containing two hydroxyl groups (–OH groups). An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. The most common industrial diol is ethylene glycol. Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol HO−(CH)−OH, and propylene-1,3-diol, or beta propylene glycol, HO−CH−CH−CH−OH. A geminal diol has two hydroxyl groups bonded to the same atom. These species arise by hydration of the carbonyl compounds. The hydration is usually unfavorable, but a notable exception is formaldehyde which, in water,

title: Diethylene glycol

text: Diethylene glycol Diethylene glycol (DEG) is an organic compound with the formula (HOCHCH)O. It is a colorless, practically odorless, poisonous, and hygroscopic liquid with a sweetish taste. It is miscible in water, alcohol, ether, acetone, and ethylene glycol. DEG is a widely used solvent. It can be a contaminant in consumer products; this has resulted in numerous epidemics of poisoning since the early 20th century. DEG is produced by the partial hydrolysis of ethylene oxide. Depending on the conditions, varying amounts of DEG and related glycols are produced. The resulting product is two ethylene glycol molecules joined by an ether

title: Deicing fluid

text: fluids such as collecting used fluid and using the maximum dilution consistent with safety. Deicing fluid Ground deicing of aircraft is commonly performed in both commercial and general aviation. The fluids used in this operation are called deicing or anti-icing fluids. The abbreviations ADF (Aircraft Deicing Fluid) or AAF (Aircraft Anti-icing Fluid) are commonly used. Deicing fluids come in a variety of types, and are typically composed of ethylene glycol (EG) or propylene glycol (PG), along with other ingredients such as thickening agents, surfactants (wetting agents), corrosion inhibitors, and colored, UV-sensitive dye. Propylene glycol-based fluid is more common due to

title: Diol

text: water, the geminal diol (HC(OH), methanediol) is favored. Other examples are the cyclic geminal diols decahydroxycyclopentane (C(OH)) and dodecahydroxycyclohexane (C(OH)), which are stable, whereas the corresponding oxocarbons (CO and CO) do not seem to be. Diol A diol is a chemical compound containing two hydroxyl groups (–OH groups). An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. The most common industrial diol is ethylene glycol. Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol HO−(CH)−OH, and propylene-1,3-diol, or beta propylene glycol, HO−CH−CH−CH−OH.

title: Diethylene glycol dinitrate

text: packages) retaining only a few specialist uses. The medical application was never widespread, the standard nitroglycerine being faster acting and almost literally dirt cheap; oral nitrates in any case being only palliative, not an effective treatment. Triethylene glycol dinitrate, diethylene glycol dinitrate, and trimethylolethane trinitrate are being considered as replacements for nitroglycerin in propellants. Diethylene glycol dinitrate Diethylene glycol dinitrate is a nitrated alcohol ester produced by the action of concentrated nitric acid, normally admixed with an excess of strong sulfuric acid as a dehydrating agent, upon diethylene glycol. Diethylene glycol dinitrate is a colorless, odorless, viscous, oily liquid, with

title: Glycol cleavage

text: Glycol cleavage Glycol cleavage is a specific type of organic chemistry oxidation. The carbon–carbon bond in a vicinal diol (glycol) is cleaved and instead the two oxygen atoms become double-bonded to their respective carbon atoms. Depending on the substitution pattern in the diol, these carbonyls can be either ketones or aldehydes. Glycol cleavage is an important reaction in the laboratory because it is useful for determining the structures of sugars. After cleavage takes place the ketone and aldehyde fragments can be inspected and the location of the former hydroxyl groups ascertained. Periodic acid (HIO) and lead tetraacetate (Pb(OAc)) are the

title: Thymine glycol

text: rate, and that a higher rate of oxidative damage might cause a higher rate of cellular aging. Base excision repair is a major DNA repair pathway for removal of oxidative DNA damages. The rate of repair of thymine glycol damage in human fibroblasts was found to decrease with age. Brain samples from humans who died of stroke were found to be deficient in base excision repair of thymine glycol as well as other types of oxidative damages. It was suggested that impaired base excision repair is a risk factor for ischemic brain injury. Thymine glycol Thymine glycol (5,6-dihydroxy-5,6-dihydrothymine) is one

title: Neopentyl glycol

text: Neopentyl glycol Neopentyl glycol (IUPAC name: 2,2-dimethylpropane-1,3-diol) is an organic chemical compound. It is used in the synthesis of polyesters, paints, lubricants, and plasticizers. When used in the manufacture of polyesters, it enhances the stability of the product towards heat, light, and water. By esterification reaction with fatty or carboxylic acids, synthetic lubricating esters with reduced potential for oxidation or hydrolysis, compared to natural esters, can be produced. Neopentyl glycol is synthesized industrially by the aldol reaction of formaldehyde and isobutyraldehyde. This creates the intermediate hydroxypivaldehyde, which can be converted to neopentyl glycol with either excess formaldehyde or catalytic hydrogenation

title: Ethylene glycol

text: base catalyst in a second step to produce mono-ethylene glycol in 98% selectivity. The carbon dioxide is released in this step again and can be fed back into the process circuit. The carbon dioxide comes in part from the ethylene oxide production, where a part of the ethylene is completely oxidized. Ethylene glycol is produced from carbon monoxide in countries with large coal reserves and less stringent environmental regulations. The oxidative carbonylation of methanol to dimethyl oxalate provides a promising approach to the production of C-based ethylene glycol. Dimethyl oxalate can be converted into ethylene glycol in high yields (94.7%)

title: Neopentyl glycol

text: of the aldehyde group to an alcohol group. It is used as a protecting group for ketones, for example in gestodene synthesis. Reaction of neopentyl glycol with 2,6-di-tert-butylphenol gives CGP-7930. Neopentyl glycol Neopentyl glycol (IUPAC name: 2,2-dimethylpropane-1,3-diol) is an organic chemical compound. It is used in the synthesis of polyesters, paints, lubricants, and plasticizers. When used in the manufacture of polyesters, it enhances the stability of the product towards heat, light, and water. By esterification reaction with fatty or carboxylic acids, synthetic lubricating esters with reduced potential for oxidation or hydrolysis, compared to natural esters, can be produced. Neopentyl glycol

title: Polyethylene glycol

text: in biomedicine, as dispersing agents, as solvents, in ointments, in suppository bases, as tablet excipients, and as laxatives. Some specific groups are lauromacrogols, nonoxynols, octoxynols, and poloxamers. Macrogol, used as a laxative, is a form of polyethylene glycol. The name may be followed by a number which represents the average molecular weight (e.g. macrogol 3350, macrogol 4000 or macrogol 6000). The production of polyethylene glycol was first reported in 1859. Both A. V. Laurence and Charles Adolphe Wurtz independently isolated products that were polyethylene glycols. Polyethylene glycol is produced by the interaction of ethylene oxide with water, ethylene glycol, or