Trimethylene glycol dinitrate

Trimethylene glycol dinitrate, 1,3-propylene glycol dinitrate (1,3-propanediol dinitrate) or nitropropylene glycol 

Concentrated nitric acid decomposes it with oxidation. 

The chemical stability of trimethylene glycol dinitrate is excellent. A sample kept at a temperature of 75°C for a period of 25 days does not decompose. In the heat test, the iodide-starch paper is coloured only because of the volatility of the substance. 

Most of the trimethylene glycol can be separated from glycerine by distillation since glycol has a significantly lower boiling point. 

The presence of glycol does not have any adverse effect on nitration, it merely reduces the yield. 

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Propylene glycol dinitrate is a colorless liquid of characteristic aromatic odor, more volatile and less viscous than trimethylene glycol dinitrate with which it is isomeric. Its specific gravity (20°/4°) is 1.368 at 20°. It boils at 92° at 10 mm., and does not freeze at —20°. Its solubilities, gelatinizing power, and explosive properties are substantially the same as those of its isomer. Indeed, Naoum 60 reports that it gave exactly the same expansion as trimethylene glycol dinitrate in the Trauzl lead block test, namely, 540 cc. 

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