2,3-プロパンジオール

外観

無色澄明の液体

性質

1,2-プロパンジオールは、プロパンの1位と3位の炭素にヒドロキシ基が結合した構造です。中央の炭素はキラル炭素となっているため、鏡像異性体が存在します。工業的には、主に酸化プロピレンの加水分解によって合成されてきました。別の合成法として、1,2-ジクロロプロパンを炭酸水素ナトリウム水溶液で処理することによっても合成することができます。

定義

PGはプロピレングリコールの表示名称である。本品は、次の化学式で表される二価アルコールである。

溶解性

水, アルコール, エーテルに可溶。水及びエタノールに極めて溶けやすい。

解説

プロピレングリコール化学式 CH3CHOHCH2OH 。プロピレンクロロヒドリンを炭酸ナトリウムと水で処理して得られる無色粘稠な液体。沸点 188℃。溶剤，不凍液，殺菌剤としても用いられる。可塑剤やポリエステル樹脂の原料に使われ，医薬として水性膏剤，水に難溶の物質の注射用溶剤に用いられる。

用途

食品加工剤(香料、色素の溶剤、保存剤、湿潤剤)。

用途

有機合成原料、ポリエステル樹脂

用途

合成樹脂、可塑剤、界面活性剤、溶剤、保存剤、湿潤剤。

用途

繊維，樹脂，溶剤，界面活性剤，不凍液，食品加工，医薬品など多方面に用途がある。

化粧品の成分用途

保湿.湿潤剤、保水剤、減粘剤、皮膚コンディショニング剤、溶剤、香料

効能

湿潤剤, 溶解剤, 懸濁剤

商品名

プロピレングリコール (丸石製薬); プロピレングリコール (日興製薬); プロピレングリコール (日興製薬)

使用上の注意

吸湿性あり。

説明

Propylene glycol is used as antifreeze in breweries and diaries, in the manufacture of resins, as a solvent, and as an emulsifier in food. It was present as an occupational sensitizer in the color-film developer Flexicolor.

化学的特性

Propylene glycol is a colorless, odorless, syrupy liquid.

天然物の起源

Reported found in several varieties of mushrooms, roasted sesame seed, oat groats, parmesan cheese, cocoa, pecans and truffle.

使用

Next to water, propylene glycol is the most common moisturecarrying vehicle used in cosmetic formulations. It has better skin permeation than glycerin, and it also gives a pleasant feel with less greasiness than glycerin. Propylene glycol is used as a humectant because it absorbs water from the air. It also serves as a solvent for anti-oxidants and preservatives. In addition, it has preservative properties against bacteria and fungi when used in concentrations of 16 percent or higher. There is a concern that propylene glycol is an irritant at high concentrations, though it appears to be quite safe at usage levels under 5 percent.

定義

An alcohol in which the hydroxyl groups are attached to a carbon atom of a branched or straight-chain aliphatic hydrocarbon.

適応症

Propylene glycol solution (40% to 60%, v/vCH2CH[OH]CH2OH, propylene glycol) applied to the skin under plastic occlusion hydrates the skin and causes desquamation of scales. Propylene glycol, isotonic in 2% concentration, is a widely used vehicle in dermatologic preparations. Hydroalcoholic gels containing propylene glycol or other substances augment the keratolytic action of salicylic acid. Keralyt gel consists of 6% salicylic acid, 19.4% alcohol, hydroxypropylcellulose, propylene glycol, and water and is an extremely effective keratolytic agent. Overnight occlusion is used nightly until improvement is evident, at which time the frequency of therapy can be decreased to every third night or once weekly. This therapy is well tolerated, is usually nonirritating, and has been most successful in patients with X-linked ichthyosis vulgaris. Burning and stinging may occur when applied to damaged skin. Patients with other abnormalities of keratinization with hyperkeratosis, scaling, and dryness may also benefit.

調製方法

Propylene glycol generally is synthesized commercially by starting with propylene, converting to the chlorohydrin, and hydrolyzing to propylene oxide, which is then hydrolyzed to propylene glycol. It can also be prepared by other methods.

製造方法

Manufactured by treating propylene with chlorinated water to form the chlorohydrin, which is converted to the glycol by treatment with sodium carbonate solution. It is also prepared by heating glycerol with sodium hydroxide.

一般的な説明

Thick odorless colorless liquid. Mixes with water.

空気と水の反応

Water soluble.

反応プロフィール

1,2-Propanediol is hygroscopic. 1,2-Propanediol is sensitive to excessive heat (tends to oxidize at high temperatures). 1,2-Propanediol can react with oxidizing materials. 1,2-Propanediol is incompatible with acid chlorides, acid anhydrides, chloroformates, and reducing agents. 1,2-Propanediol dissolves many essential oils. A mixture of 1,2-Propanediol with hydrofluoric acid and silver nitrate was put in a glass bottle which burst 30 minutes later.

危険性

Toxic.

健康ハザード

Liquid may irritate eyes.

火災危険

1,2-Propanediol is combustible.

法規情報

プロパンジオールは燃えやすく、消防法において危険物第4類、第3石油類に分類されています。引火点は99℃なので常温で引火することはないですが、火気の近くでの取扱は厳禁です。

参考文献

使用用途

水よりも低い融点、高い沸点を生かして、溶剤や不凍液、熱媒や冷媒として利用されています。また、生物への毒性が低いことを利用して保湿剤、、防カビ剤などの食品添加物としても利用されます。

医薬品としては、駐車剤や内服薬、外用薬の溶解補助剤として調剤に用いられることがあります。工業的には、樹脂を合成する際の中間原料としても用いられてきました。また、有機化学においては、ピナコール転移を利用したケトンの合成に用いられます。

接触アレルゲン

Propylene glycol is used as a solvent, a vehicle for topical medicaments such as corticosteroids or aciclovir, an emulsifier and humectant in food and cosmetics, and as antifreeze in breweries, in the manufactures of resins. It was present as an occupational sensitizer in the color film developer Flexicolor?. Patch tests in aqua are sometimes irritant.

安全性プロファイル

Slightly toxic by ingestion, skin contact, intraperitoneal, intravenous, subcutaneous, and intramuscular routes. Human systemic effects by ingestion: general anesthesia, convulsions, changes in surface EEG. Experimental teratogenic and reproductive effects. An eye and human skin irritant. Mutation data reported. Combustible liquid when exposed to heat or flame; can react with oxidizing materials. Explosive in the form of vapor when exposed to heat or flame. May react with hydrofluoric acid + nitric acid + silver nitrate to form the explosive silver fulminate. To fight fire, use alcohol foam. When heated to decomposition it emits acrid smoke and irritating fumes.

職業ばく露

Propylene glycol is used as a solvent; emulsifying agent; food and feed additive; flavor, in manu- facture of plastics; as a plasticizer, surface-active agent; antifreeze, solvent, disinfectant, hydroscopic agent; coolant in refrigeration systems; pharmaceutical, brake fluid; and many others.

発がん性

Dewhurst et al. and Baldwin et al. in studies on the carcinogenicity of other chemicals used propylene glycol as the solvent. As a result they tested propylene glycol alone for carcinogenic activity in rats and mice. Dewhurst et al. used a single injection of 0.2 mL, whereas Baldwin et al. gave rats and mice three to five subcutaneous injections, amount not specified. In neither case were tumors observed during a period of about a year or 2 years .
Wallenious and Lecholm applied propylene glycol to the skin of rats three times a week for 14 months but found no tumor formation. Stenback and Shubik confirmed these findings when they applied propylene glycol at undiluted strength and as a 50 and 10% solution in acetone to the skin of mice during their lifetimes.
No tumors have been reported in the lifetime dietary feeding studies . In fact, Gaunt et al. specifically state that no tumors were found in the rats.

環境運命予測

Propylene glycol can be released into the environment via industrial releases or by disposal of consumer products. Propylene glycol is readily soluble in water and has a low sorption partition coefficient (KOC), so has the ability to move through soil and to leach into ground water. Because of low vapor pressure (0.1 mmHg at 25°C) and high water solubility, there is minimal volatilization to the atmosphere from surface water releases as well as substantial removal of its vapors by wet deposition. Its low octanol/water partition coefficient (KOW) indicates that bioconcentration and biomagnification should not happen. Propylene glycol is readily degraded in surface water and soil, by chemical oxidation and microbial digestion, with a short half-life (1–5 days) in aerobic or anaerobic conditions. It is also rapidly degraded in the atmosphere by photochemical oxidation, with a half-life about 1 day. Although environmental releases can and do occur (airports must monitor storm water runoff of deicing solutions), human health effects are likely to be minor, at least in comparison to effects from potential exposures in clinical scenarios.

純化方法

Dry the diol with Na2SO4, decant and distil it under reduced pressure. [Beilstein 1 IV 2468.]

不和合性

Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explo- sions. Keep away from alkaline materials, strong acids (especially nitric acid), strong bases, permanganates, dichromates; may cause a violent reaction.

廃棄物の処理

Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber.All federal, state, and local environmental regulations must be observed.