Encyclopedia   /  Alcohol & Hydroxybenzene & Ether  /  Basic Organic Chemicals  /  Pharmaceutical Intermediates
Propylene glycol structure

Propylene glycol

  • CAS:57-55-6
  • MW:76.09
  • MF:C3H8O2
Propylene glycol is used as antifreeze in breweries anddiaries, in the manufacture of resins, as a solvent, and as an emulsifier in food. It was present as anoccupational sensitizer in the color-film developerFlexicolor. View more+
 
1. Names and Identifiers
1.1 Name
Propylene glycol
1.2 Synonyms
EINECS 200-338-0; Glycerol Impurity 3(Glycerol EP Impurity C); MFCD00064272; Propyledne glycol; Propylene glycol 57-55-6; Propylene Glycol, Reagent; Propyleneglycol Manufacturer; PROPYLENEGLYCOL, REAGENT (ACS)PROPYLENEGLYCOL, REAGENT (ACS)PROPYLENEGLYCOL, REAGENT (ACS); PROPYLENEGLYCOLTECHGRADE;
1.3 CAS No.
57-55-6
1.4 CID
1030
1.5 EINECS
200-338-0; 939-872-0
1.6 Molecular Formula
C3H8O2
1.7 Inchi
InChI=1S/C3H8O2/c1-3(5)2-4/h3-5H,2H2,1H3
1.8 InChkey
DNIAPMSPPWPWGF-UHFFFAOYSA-N
1.9 Canonical Smiles
CC(CO)O
1.10 Isomers Smiles
CC(CO)O
2. Properties
2.1 Vapour pressure
2.62
2.2 Viscosity
0.581 cP at 20 °C
2.3 VaporPhaseIRSpectra
DIGILAB FTS-14
2.4 VaporDensity
2.62
2.5 Appearance
Clear viscous liquid
2.6 Atmospheric OH Rate Constant
1.20e-11 cm3/molecule*sec
2.7 Storage
Hygroscopic. Store under Nitrogen. Ambient temperatures.
2.8 Autoignition Temperature
700 °F (USCG, 1999)
2.9 Carcinogenicity
Dewhurst et al. andBaldwin et al. in studies on the carcinogenicity ofother chemicals used propylene glycol as the solvent. As aresult they tested propylene glycol alone for carcinogenicactivity in rats and mice. Dewhurst et al. used a singleinjection of 0.2 mL, whereas Baldwin et al. gave ratsand mice three to five subcutaneous injections, amount notspecified. In neither case were tumors observed during aperiod of about a year or 2 years .Wallenious and Lecholm applied propylene glycolto the skin of rats three times a week for 14 months but foundno tumor formation. Stenback and Shubik confirmedthese findings when they applied propylene glycol at undilutedstrength and as a 50 and 10% solution in acetone to theskin of mice during their lifetimes.No tumors have been reported in the lifetime dietaryfeeding studies . In fact, Gaunt et al. specifically state that no tumors were found in the rats.
2.10 Color/Form
APHA: ≤10
2.11 Contact Allergens
Propylene glycol is used as a solvent, a vehicle fortopical medicaments such as corticosteroids or aciclovir,an emulsifier and humectant in food and cosmetics,and as antifreeze in breweries, in the manufacturesof resins. It was present as an occupational sensitizerin the color film developer Flexicolor?. Patch tests inaqua are sometimes irritant.
2.12 Heat of Combustion
431.0 kg cal/mole
2.13 Heat of Vaporization
168.6 cal/g at BP
2.14 Odor
Practically odorless
2.15 PH
6-8 (100g/l, H2O, 20℃)
2.16 pKa
14.49±0.20(Predicted)
2.17 Water Solubility
Solubility in water: miscible
2.18 Spectral Properties
Index of refraction: 1.4324 at 20 deg C/D
SADTLER REFERENCE NUMBER: 267 (IR, PRISM); 92 (IR, GRATING)
IR: 5974 (Coblentz Society Spectral Collection)
UV: 5-12 (Organic Electronic Spectral Data, Phillips et al, John Wiley & Sons, New York)
NMR: 45 (Varian Associates NMR Spectra Catalogue)
MASS: 95 (Atlas of Mass Spectral Data, John Wiley & Sons, New York)
2.19 Stability
At cool temperatures, propylene glycol is stable in a well-closed container, but at high temperatures, in the open, it tends to oxidize, giving rise to products such as propionaldehyde, lactic acid, pyruvic acid, and acetic acid. Propylene glycol is chemically stable when mixed with ethanol (95%), glycerin, or water; aqueous solutions may be sterilized by autoclaving.
2.20 StorageTemp
Store at RT.
2.21 Surface Tension
40.1 dynes/cm at 25 °C
3. Use and Manufacturing
3.1 Definition
An alcohol in which the hydroxyl groups are attached to a carbon atom of a branched or straight-chain aliphatic hydrocarbon.
3.2 Description
Propylene glycol (CAS 57-55-6) is a colorless, odorless, and viscous liquid. It has a basic structure consisting of two hydroxyl groups attached to a propylene backbone. This chemical is highly soluble in water, making it miscible in all proportions. It also exhibits low volatility and a low freezing point, which contributes to its wide range of applications. Propylene glycol is commonly used as a solvent, humectant, and emulsifier in various industries.

Applicable Fields
Pharmaceutical Industry: Propylene glycol is widely used in the pharmaceutical industry as a solvent and excipient. It helps to dissolve and stabilize active pharmaceutical ingredients in medications, ensuring their uniform distribution. The mechanism of action involves enhancing the solubility and bioavailability of drugs.

Food and Beverage Industry: In the food and beverage industry, propylene glycol serves as a food additive and flavor carrier. It is commonly used in products such as baked goods, dairy products, and beverages. The mechanism of action involves improving texture, preventing crystallization, and enhancing flavor dispersion.

Cosmetics and Personal Care Industry: Propylene glycol is a common ingredient in cosmetics, skincare products, and personal care items. It acts as a humectant, helping to retain moisture in the skin and hair. It also functions as a solvent for various active ingredients. The mechanism of action involves attracting and retaining water molecules, keeping the skin and hair hydrated.

Storage Conditions
Store in a cool and dry place.
3.3 General Description
Thick odorless colorless liquid. Mixes with water.
3.4 Potential Exposure
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; coolantin refrigeration systems; pharmaceutical, brake fluid; andmany others.
3.5 Produe Method
Propylene glycol generally is synthesized commercially bystarting with propylene, converting to the chlorohydrin, andhydrolyzing to propylene oxide, which is then hydrolyzedto propylene glycol. It can also be prepared by othermethods.
3.6 Purification Methods
Dry the diol with Na2SO4, decant and distil it under reduced pressure. [Beilstein 1 IV 2468.]
3.7 Usage
Propylene glycol is used for similar applications as other glycols.Propylene glycol is an important raw material for unsaturated polyester, epoxy resin, and polyurethane resin. The use amount in this area accounts for about 45% of the total consumption of propylene glycol. Such unsaturated polyester is used extensively for reinforced plastics and surface coatings. Propylene glycol is excellent in viscosity and hygroscopicity and is non-toxic, and thus is widely used as hygroscopic agent, antifreeze, lubricants and solvents in the food, pharmaceutical and cosmetic industry. In the food industry, propylene glycol reacts with fatty acid to give propylene ester of fatty acids, and is mainly used as food emulsifier; Propylene glycol is a good solvent for flavorings and pigments. Propylene glycol is commonly used as solvents, softeners and excipients, etc. in the pharmaceutical industry for the manufacture of various types of ointments and salves. Propylene glycol is also used as a solvent and a softener for cosmetic since it has good mutual solubility with various spices. Propylene glycol is also used as tobacco moisturizing agents, antifungal agents, food processing equipment lubricants and solvents for food marking ink. Aqueous solution of propylene glycol is an effective anti-freeze agent.
3.8 Waste Disposal
Dissolve or mix thematerial with a combustible solvent and burn in a chemicalincinerator equipped with an afterburner and scrubber.All federal, state, and local environmental regulations mustbe observed. Propylene glycol Preparation Products And Raw materials Preparation Products
4. Safety and Handling
4.1 Exposure Standards and Regulations
Substance added directly to human food affirmed as generally recognized as safe (GRAS).
Propylene glycol used as an emulsifying agent in animal drugs, feeds, and related products is generally recognized as safe when used in accordance with good manufacturing or feeding practice.
Propylene glycol used as a general purpose food additive in animal drugs, feeds, and related products is generally recognized as safe when used in accordance with good manufacturing or feeding practice.
Drug products containing certain active ingredients offered over-the-counter (OTC) for certain uses. A number of active ingredients have been present in OTC drug products for various uses, as described below. However, based on evidence currently available, there are inadequate data to establish general recognition of the safety and effectiveness of these ingredients for the specified uses: propylene glycol is included in pediculicide drug products.
Ophthalmic demulcents. The active ingredients of the product consist of any of the following, within the established concentrations for each ingredient: Propylene glyol, 0.2 to 1 percent.
The Food and Drug Administration has determined that propylene glycol in or on cat food is not generally recognized as safe and is a food additive subject to section 409 of the Federal Food, Drug, and Cosmetic Act (the act). The Food and Drug Administration also has determined that this use of propylene glycol is not prior sanctioned.
The Food and Drug Administration has determined that propylene glycol in or on cat food has not been shown by adequate scientific data to be safe for use. Use of propylene glycol in or on cat food causes the feed to be adulterated and in violation of the Federal Food, Drug, and Cosmetic Act (the act), in the absence of a regulation providing for its safe use as a food additive under section 409 of the act, unless it is subject to an effective notice of claimed investigational exemption for a food additive under part 570.17 of this chapter, or unless the substance is intended for use as a new animal drug and is subject to an approved application under section 512 of the act or an effective notice of claimed investigational exemption for a new animal drug under part 511 of this chapter.
4.2 Octanol/Water Partition Coefficient
log Kow = -0.92
4.3 Fire Hazard
1,2-Propanediol is combustible.
4.4 Other Preventative Measures
SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.
SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.
Above 99 deg C use a closed system, ventilation.
Propylene glycol should be handled in a well-ventilated environment; eye protection is recommended.
4.5 Cleanup Methods
SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.
Collect leaking and spilled liquid in sealable containers as far as possible. Wash away spilled liquid with plenty of water.
4.6 DisposalMethods

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

4.7 Fire Fighting Procedures
Water fog, alcohol foam, carbon dioxide, dry chemical.
In case of fire, keep drums, etc, cool by spraying water.
4.8 FirePotential
Combustible liquid when exposed to heat or flame.
4.9 Safety Profile
Slightly toxic byingestion, skin contact, intraperitoneal,intravenous, subcutaneous, andintramuscular routes. Human systemiceffects by ingestion: general anesthesia,convulsions, changes in surface EEG.Experimental teratogenic and reproductiveeffects. An eye and human skin irritant.Mutation data reported. Combustible liquidwhen exposed to heat or flame; can reactwith oxidizing materials. Explosive in theform of vapor when exposed to heat orflame. May react with hydrofluoric acid +nitric acid + silver nitrate to form theexplosive silver fulminate. To fight fire, usealcohol foam. When heated todecomposition it emits acrid smoke andirritating fumes.
4.10 Formulations/Preparations
GRADE: refined, technical, USP, FCC, feed
Both the industrial-grade and USP grade have at least 99.5% purity.
4.11 Incompatibilities
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.
4.12 Protective Equipment and Clothing
Mildly irritating to the eyes.
May cause primary skin irritation in some people, possibly due to dehydration, but the material is not a sensitizer.
May cause transitory stinging, blepharospasm, and lacrimation.
4.13 Reactivities and Incompatibilities
Reacts with strong oxidants, causing fire hazard.
Propylene glycol is incompatible with oxidizing reagents such as potassium permanganate.
No significantly dangerous substances are produced after contact with light, humidity or commonly available chemicals. Propylene glycol may react with hydrofluoric acid + nitric acid + silver nitrate to form the explosive silver fulminate.
A chemical polishing mixture of hydrofluoric acid, propylene glycol, and silver nitrate was put into a closed glass bottle which burst 30 min later, and formation of silver fulminate was suggested. However, in absence of the silver salt such mixtures evolve gas and should not be stored in any event, especially after use for metal polishing, when the dissolved metal(s) tend to further destabilize the mixture.
4.14 Report
Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.
4.15 Skin, Eye, and Respiratory Irritations
Mildly irritating to the eyes.
May cause primary skin irritation in some people, possibly due to dehydration, but the material is not a sensitizer.
May cause transitory stinging, blepharospasm, and lacrimation.
4.16 Safety
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.
Safety Statements: 24/25
S24/25:Avoid contact with skin and eyes.
WGK Germany: 1
RTECS: TY2000000
HS Code: 29053200
4.17 Sensitive
Hygroscopic
4.18 Specification
Propylene Glycol (CAS NO.57-55-6) is also named as (+-)-1,2-Propanediol ; (+-)-Propylene glycol ; (RS)-1,2-Propanediol ; 1,2-Dihydroxypropane ; 1,2-Propylene glycol ; 1,2-Propylenglykol ; 1,2-Propylenglykol [German] ; 2,3-Propanediol ; 2-Hydroxypropanol ; 3-01-00-02142 (Beilstein Handbook Reference) ; AI3-01898 ; BRN 1340498 ; CCRIS 5929 ; Caswell No. 713 ; DL-1,2-Propanediol ; Dowfrost ; EPA Pesticide Chemical Code 068603 ; FEMA No. 2940 ; HSDB 174 ; Isopropylene glycol ; Methylethyl glycol ; Methylethylene glycol ; Monopropylene glycol ; Sirlene ; Solar Winter BAN ; Solargard P ; Trimethyl glycol ; UNII-6DC9Q167V3 ; Ucar 35 ; alpha-Propyleneglycol ; dl-Propylene glycol . Propylene Glycol (CAS NO.57-55-6) is clear viscous liquid. It is mixes with water and dissolves many essential oils. Propylene Glycol is sensitive to excessive heat (tends to oxidize at high temperatures). It can react with oxidizing materials. And it is incompatible with acid chlorides, acid anhydrides, chloroformates, and reducing agents.Liquid may irritate eyes. Propylene Glycol is combustible.
4.19 Toxicity
LD50 orally in Rabbit: 19400 - 36000 mg/kg LD50 dermal Rabbit 20800 mg/kg
5. MSDS

2.Hazard identification

2.1 Classification of the substance or mixture

Not classified.

2.2 GHS label elements, including precautionary statements

Pictogram(s) No symbol.
Signal word

No signal word.

Hazard statement(s)

none

Precautionary statement(s)
Prevention

none

Response

none

Storage

none

Disposal

none

2.3 Other hazards which do not result in classification

none

6. NMR Spectrum
13C NMR : in CDCl3  
13C NMR : Predict  
1H NMR : 90 MHz in CDCl3  
1H NMR : in CDCl3  
1H NMR : Predict  
IR : liquid film  
Raman : 4880 A,200 M,liquid  
Mass  
7. Synthesis Route
57-55-6Total: 263 Synthesis Route
 
75-56-9
75-56-9 118 Suppliers
 
57-55-6
57-55-6 965 Suppliers
 
95-96-5
95-96-5 50 Suppliers
 
57-55-6
57-55-6 965 Suppliers
8. Precursor and Product
precursor:
product:
9. Computed Properties
10.Other Information
Usage
1,2-Propanediol, ACS is used as a substitute for ethylene glycol and glycerol. It is a good solvent for resins. It dissolves many essential oils but is immiscible with fixed oils.
Usage
1,2-Propanediol is used in antifreeze and deicing solutions for cars, boats and aircraft. It is also used to create harmless, artificial smoke for training and theatrical purposes. It is used as a humectant solvent and preservative in food. It acts as a solvent for paints and plastics. Further, it is used in the manufacturing of lactic acid by green catalytic oxidation, propanal and propylene carbonate. It is also employed in veterinary medicine as an oral treatment for hyperketonaemia in ruminants. In addition to this, it reacts with propylene oxide to prepare oligomers.
Storage features
Separated from strong oxidants and alkalis. Dry. Well closed. Ventilation along the floor.
11. Toltal 913 Suppliers View more
Tel: Update Time:2024/11/15
Tel: Update Time:2024/08/08
Tel: Update Time:2024/11/15
Tel: Update Time:2024/11/15
Tel: Update Time:2024/09/17
12. Related Questions
What are the side effects of propylene glycol? Introduction: Propylene Glycol, as a common compound, is widely used in food, medicine, cosmetics and other fields. However, in addition to its various purposes, we also need to pay attention to the ..
How to deal with PROPYLENE GLYCOL Introduction: Propylene Glycol, as a common compound, is widely used in food, medicine, cosmetics and other fields. However, in the process of use and production, we also need to pay attention to how..
What is the use of propylene glycol ( 3) Elberry is a component of soothing and moisturizing the skin. They play an important role in the treatment of dry skin skin care products. PROPYLENE GLYCOL is a moisturizing agent because it for..
Is propylene GlyCol's flammable? Summary: Propylene Gycol, also known as 1,2-PROPYLENE GLYCOL, is a common compound that is widely used in food, medicine, cosmetics and other fields. However, it has attracted much attention to wheth..
13. Realated Product Infomation
 
 
 
Cancel
 
Popular Searches
Request For Quotation