MPG

Monopropylene glycol (MPG)
Physical characteristics: transparent substance

Chemical formula: C3H8O2

Molecular weight: 76.09 g / mol

Container type, Barrel / IBS / Tanker

Low volatility transparent solvent. Fully miscible with water, alcohol and chloroform. It has hygroscopic properties.

Areas of use:

-In food, drinks, essential oils, pharmaceutical and perfumery and cosmetic industries.

-In water purification processes.

- Used to extract substances from mixtures.

Monopropylene glycol (1,2-propanediol) min. 99.7%  

Monopropylene glycol is used in the production of unsaturated polyester resins, elastic polyurethanes, alkyd resins.

Monopropylene glycol is used as a solvent for natural and synthetic substances in the preparation of ointments, pastes, creams, shampoos, etc.

Monopropylene glycol is used as a solvent, plasticizer, as a basis for the production of low-freezing, anti-icing, hydraulic and hydraulic brake fluids.

Monopropylene glycol is used as an energy additive intended for cattle to increase milk yield, fat, in milk, and has antiseptic properties.

Basic properties 
1,2-propylene glycol is a clear viscous liquid. Its density is lower than that of ethylene glycol and glycerin , but higher than that of ethanol . The viscosity of propylene glycol is higher than that of ethylene glycol and monohydric alcohols, especially at low temperatures [1] [2] [3] [4] [5] [6] . IR and mass spectra of 1,2-propylene glycol are listed on the NIST website .

Solubility 
Propylene glycol is a good solvent for a different class of compounds. Most low molecular weight organic compounds containing oxygen and nitrogen are completely mixed with it:

monohydric alcohols ( methyl , ethyl , propyl , isopropyl , n-butyl , n-amyl, phenylethyl , etc.)
ethylene and propylene glycols and their esters
acids ( acetic , diethylacetic, valeric, oleic, etc.)
aldehydes (anise, benzoic, mustard, salicylic, furfural, citral) and ketones (acetone, α-ionone, methyl isopropyl and methyl isobutyl ketones )
esters (ethyl-, ethylchloro-, n-butyl-, amyl- and isoamylacetates, tri-n-butylphosphate, n-butyl-lactone, etc.)
amines and other nitrogen-containing compound ( ethanol- and diethanolamine , diisopropylamine, di-n-butylamine, di-n-amylamine, α-methylbenzylamine, α-metilbenzildimetilamin, 2-phenylethylamine, diethylenetriamine, triethylenetetramine, pyridine , dimethylformamide , n-amiltsianid etc. .).
Physicochemical properties of aqueous solutions of propylene glycol 
Propylene glycol is miscible with water.

Chemical properties of propylene glycol 
Propylene glycol is known as two isomers : 1,2-propylene glycol { displaystyle { mathsf {CH_ {3} ! ! - ! ! CHOH ! - ! CH_ {2} ! - ! OH}}}{ mathsf {CH_ {3} ! ! - ! ! CHOH ! - ! CH_ {2} ! - ! OH}} and 1,3-propylene glycol { displaystyle { mathsf {HO ! - ! CH_ {2} ! ! - ! ! CH_ {2} ! - ! CH_ {2} ! - ! OH}}}{ mathsf {HO ! - ! CH_ {2} ! ! - ! ! CH_ {2} ! - ! CH_ {2} ! - ! OH}}... 1,3-Propylene glycol is more reactive than 1,2-propylene glycol and is prone to polymerization.

Due to the presence of an asymmetric carbon atom, there are two optical isomers: one that rotates the plane of polarization of light to the left, (-) - shape and the other - to the right, (+) - shape. Propylene glycol, obtained commercially by hydration of propylene oxide, is a racemic mixture of both optical isomers ( racemate ).

Optical isomers of propylene glycol can be obtained from left and right-handed propylene oxide. In addition, the levogyrate isomer is obtained upon reduction of the levorotatory ester of lactic acid, and the dextrorotatory isomer - upon hydrogenation of levorotatory 3-iodo-1,2-propylene glycol over nickel [12] .

Optical isomers of propylene glycol can also be obtained from racemate by fractionation of cyclic ketals of propylene glycol and 1-menthone and subsequent acidic hydrolysis of individual ketals [13] . A method is proposed for the isolation of (-) - and (+) - propylene glycols from a solution of racemate in an organic solvent (n-propanol, sec-butanol, acetone and its mixture with ethyl ether or ethyl acetate, etc.) by "seeding" the solution with crystalline propylene glycol cooled to temperatures below −29 ° C  .

In terms of chemical properties, 1,2-propylene glycol is a typical glycol. Form glycolate with alkali metals and alkalis, mono- and disubstituted esters with carboxylic acids and anhydrides; esterification of 1,2-propylene glycol and monoesters leads to diesters. When dehydrated in the presence of acids or alkalis, 1,2-propylene glycol forms a mixture of dimethyl-1,4-dioxanes, in the presence of Н 3 РО 4 at 250 ° C-propionic aldehyde, in the presence of АlРО 4  - allyl alcohol (2-propene-1- ol) CH 2 = CH-CH 2 -OH and acetone. The catalytic dehydrogenation of 1,2-propylene glycol gives acetol CH 3 -CO-CH 2-OH or propionic aldehyde, propionic acid, methylglyoxal, etc. 
During the oxidation of 1,2-propylene glycol, the reaction products are acetone, propionaldehyde, lactic acid, formaldehyde, acetaldehyde, etc.

Toxicology 
E1520 (propylene glycol) additive is approved for use in most countries of the world .

Propylene glycol production 
Production diagram 
The production of propylene glycol is carried out by hydration of propylene oxide at a temperature of 160 to 200 degrees and at a pressure of about 1.6 MPa. In this case, 85.5% of 
propylene glycol, 13% of dipropylene glycol and 1.5% of tripropylene glycol are released. Allocate glycols in a vacuum on a rectification column. The guaranteed shelf life of the 
product is one year from the date of manufacture. Food grade propylene glycol has a shelf life of about two years. During operation, one should not forget that when solutions 
containing propylene glycol overheat, the base and additives decompose, therefore, the thermophysical properties of the solution may deteriorate.

The use of propylene glycol 
Antifreezes (coolants, coolants) 
Low-freezing heat carriers based on an aqueous solution of propylene glycol are widely used in various industries as heat carriers (antifreezes), including in heating, ventilation, 
air conditioning systems for residential buildings and public buildings, in refrigeration systems for food production, as well as in other heat exchange equipment in the interval 
temperatures from -40 ° C to +108 ° C.

Dependence of the freezing point of coolants on the concentration of propylene glycol in them:

freezing t, ° C    −40    −30    −20    −10    −5    0
Content,% mass    54    48    39    25    fifteen    1
At home, you can determine the freezing temperature t freezing ° C of the operating coolant by density. The dependence of the density on the freezing point for aqueous solutions 
of propylene glycol are shown in Table 2.

The dependence of the density on the temperature of the onset of crystal formation of propylene glycol:

freezing t, ° C    −40    −30    −20    −10    −5    0
Density, kg / m3    1040    1037    1031    1019    1010    999.3
1,2-Propylene glycol is used:

in the production of unsaturated polyester resins (for the construction industry and automobile production), elastic polyurethanes, alkyd resins;
as a solvent for natural and synthetic substances in the preparation of ointments, pastes, creams, shampoos, etc. in the pharmaceutical and cosmetic industries;
in the food industry as a solvent for food additives and a tobacco moisturizer. 1,2-Propylene glycol has moderate preservative and bactericidal properties;
For disinfection of premises at food industry enterprises (sprayed in the air in the form of an aerosol);
in the manufacture of brake fluids, antifreezes, anti-icing fluids and coolants;
as a plasticizer in the production of cellophane and polyvinyl chloride films;
in smoke machines for creating visual effects at concerts, variety shows, in the film industry;
In connection with the replacement of ethylene glycol ethers with less toxic compounds, the use of 1,2-propylene glycol ethers is increasing;
in liquids for electronic steam generators and ENDS;
In the food industry, propylene glycol is registered as a food additive E1520 as a humectant, emollient and dispersing agent.

buy monopropylene glycol
mpg satın al