Propylene glycol dinitrate

• CAS: 6423-43-4
• Catalog Number: ACM6423434
• Category: Main Products
• Molecular Weight: 166.09
• Molecular Formula: C3H6N2O6
• Synonyms: Isopropylene nitrate
• Appearance: Colorless liquid

Case Study

Propylene Glycol Dinitrate as Explosive Taggant for Detection and Identification

Fettaka, Hichem, et al. Central European Journal of Energetic Materials 13.3 (2016): 627-640.

This forensic chemistry study evaluates the potential use of propylene glycol dinitrate (PGDN) as an explosive taggant for pre-blast detection. The investigation was motivated by the need to identify suitable taggants that possess adequate vapor pressure for detection while maintaining good energetic compatibility with explosive compositions. The work characterizes the key physical and thermal properties of PGDN that are relevant to its performance as a taggant, including vapor pressure, enthalpy of vaporization, and thermal decomposition characteristics.
Experimental Protocol: PGDN was synthesized in the laboratory by nitration of propylene glycol using a mixed nitric-sulfuric acid nitration system. The product was purified by washing with water and aqueous sodium carbonate solution until neutral, then characterized by GC-MS and FTIR spectroscopy to confirm purity and identity. Thermal decomposition was studied using differential scanning calorimetry (DSC) at four different heating rates, allowing determination of activation energy by the Ozawa and Kissinger methods. Vapor pressure was measured using thermogravimetric analysis with benzoic acid as reference material, applying the Langmuir and Clausius-Clapeyron equations to calculate the vapor pressure at different temperatures. Gas chromatography-mass spectrometry was used to confirm purity and identify any impurities.
Performance Evaluation: The synthesis yielded PGDN in 63-65% yield with high purity as confirmed by GC-MS and FTIR spectroscopy. DSC analysis showed that decomposition occurs between 170-230°C with an average heat of decomposition of 4011 J·g-1. The activation energy for decomposition was calculated to be approximately 134 kJ·mol-1 by both the Ozawa and Kissinger methods, consistent with literature values. TG-MS analysis identified the principal gaseous decomposition products as NO, C3H8, and NO2, which are easily detectable by mass spectrometry.

Propylene Glycol Dinitrate as Oxidizer in Otto Fuel II Monopropellant Combustion

Fuller, Mark E., et al. Proceedings of the Combustion Institute 37.4 (2019): 5671-5677.

Propylene glycol dinitrate (PGDN) serves as the primary oxidizer in Otto Fuel II, a liquid monopropellant blend (76 wt% PGDN, 22.5% dibutyl sebacate, 1.5% 2-nitrodiphenylamine). Its rapid thermal decomposition drives combustion, but incomplete conversion may contribute to engine fouling via condensed byproducts.
Experimental/Computational Protocol: Density functional theory (M11/jun-cc-pVTZ) and RRKM/master equation calculations were performed for PGDN decomposition. A detailed kinetic mechanism (547 species, 6191 reactions) was generated using RMG and implemented in a 1D burner-stabilized flame simulation (CANTERA) at 10 atm, 400 K inlet, with mass flow 0.1 kg/s.
Performance Evaluation: PGDN decomposes primarily via O-NO2 cleavage (rate constants ~10⁷ s^-1 at 1000 K), producing CH2O, CH3CHO, and NO2. HONO elimination is ~6 orders of magnitude slower. The flame front occurs at ~2 mm, peaking at 1495 K. Post-flame temperature drops to ~1410 K. DBS (95% consumed) and NDPA decompose, forming aromatic radicals (e.g., phenyl-aminyl) that recombine with DBS fragments to yield high-molecular-weight species (≥30 heavy atoms). Joback method estimates boiling points >1400 K for these products, exceeding post-flame temperatures, suggesting condensation and potential engine gunk formation.
Conclusion: Propylene glycol dinitrate drives rapid combustion, but its decomposition products enable formation of condensable heavy byproducts, linking chemical kinetics to observed engine fouling.

Custom Q&A

What is the molecular formula of propylene glycol dinitrate?

The molecular formula of propylene glycol dinitrate is CH3CNO2OHCHNO2OHC3H6N2O6CH3CHONO2CH2ONO2.

What are some synonyms for propylene glycol dinitrate?

Some synonyms for propylene glycol dinitrate are isopropylene nitrate, propylene dinitrate, propylene nitrate, and propane-1,2-diyl dinitrate.

What is the molecular weight of propylene glycol dinitrate?

The molecular weight of propylene glycol dinitrate is 166.09 g/mol.

Is propylene glycol dinitrate soluble in water?

Propylene glycol dinitrate is slightly soluble in water (7.97 g/L H2O at 24.85 °C).

What is the CAS number of propylene glycol dinitrate?

The CAS number of propylene glycol dinitrate is 6423-43-4.

What is the InChIKey of propylene glycol dinitrate?

The InChIKey of propylene glycol dinitrate is PSXCGTLGGVDWFU-UHFFFAOYSA-N.

What is the EC number of propylene glycol dinitrate?

The EC number of propylene glycol dinitrate is 229-180-0.

How many hydrogen bond acceptors does propylene glycol dinitrate have?

Propylene glycol dinitrate has 6 hydrogen bond acceptors.

How many rotatable bonds does propylene glycol dinitrate have?

Propylene glycol dinitrate has 3 rotatable bonds.

What is the formal charge of propylene glycol dinitrate?

The formal charge of propylene glycol dinitrate is not provided in the reference.