Trimethylolethane trinitrate (TMETN), also known as metriol trinitrate (METN, MTN, METRTN) or nitropentaglycerin, is a nitro ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

. It is a high explosive similar to nitroglycerin. It is a transparent oily liquid, colorless to light brown. It is odorless. It is used in some solid propellants and smokeless powder

Smokeless powder

Smokeless powder is the name given to a number of propellants used in firearms and artillery which produce negligible smoke when fired, unlike the older gunpowder which they replaced...

s as a plasticizer

Plasticizer

Plasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added; these include plastics, cement, concrete, wallboard, and clay. Although the same compounds are often used for both plastics and concretes the desired effects and results are...

. Its chemical formula is CH₃-C(CH₂-O-NO₂)₃.

TMETN was first prepared and patented in Italy under name Metriolo. Germans began producing it before WWII when it was demonstrated to be an erosion and flash reducing agent in smokeless powders. It is a liquid explosive with properties similar to nitroglycerin but more stable to heat. It is prepared by nitration

Nitration

Nitration is a general chemical process for the introduction of a nitro group into a chemical compound. The dominant application of nitration is for the production of nitrobenzene, the precursor to methylene diphenyl diisocyanate...

 of trimethylolethane

Trimethylolethane

Trimethylolethane is the organic compound with the formula CH3C3. This colorless solid is a triol, that is it contains three hydroxy functional groups. More specifically, it features three primary alcohol groups in a compact neopentyl structure. Its esters are known for their resistance to heat,...

 (metriol). It does not induce headaches.

TMETN can be initiated by friction, impact, and electrostatic discharge. It can be used as a high viscosity plasticizer-binder together with nitrocellulose

Nitrocellulose

Nitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton...

, but its poor coloiding properties made such use rare; long-term milling can however assist here; success can also be achieved by adding an inert plasticizer and a volatile solvent/colloiding agent.

TMETN is miscible with ether and acetone. It is insoluble in 95% sulfuric acid.

TMETN can be used as a plasticizer together, or as an alternative to, triethyleneglycol dinitrate (TEGDN).

TMETN can also be used as a monopropellant

Monopropellant

Monopropellants are propellants composed of chemicals or mixtures of chemicals which can be stored in a single container with some degree of safety. While stable under defined storage conditions, they react very rapidly under certain other conditions to produce a large volume of energetic gases...

.

Triethylene glycol dinitrate

Triethylene glycol dinitrate

Triethylene glycol dinitrate is a nitrated alcohol ester of triethylene glycol. It is used as an energetic plasticizer in explosives and propellants. Its chemical formula is O2N-O-CH2CH2-O-CH2CH2-O-CH2CH2-O-NO2. It is a pale yellow oily liquid...

, diethylene glycol dinitrate

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....

, and trimethyloleate trinitrate are being considered as replacements for nitroglycerin in propellants.