u/EUnuch_Russler

A very obscure and virtually forgotten nitric ester. Isomer of MHN, exactly the same formula, but with closer packing more symmetrical configuration. Patent reference it since 1930s in det cap applications but it hasn't seen any notable commercial utilization despite having some very favorable properties. The symmetrical configuration vs MHN indicates it is more stable to impact and friction, approaching PETN stability figures. Same applies to resistance to storage decomposition. VOD should be in the low 8km/s, melting point 95C, doesn't seem to have any issues of ETN molten sensitivity. The significant lower casting temperature vs PETN could make it a more advantageous cast booster composition with TNT. Absolutely no data on synthesis but basically MHN synthesis should apply. Should not require any heating phase and shouldn't be prone to runaways.

IMO, the assumption that PETN has a noticeable edge of ETN is anecdotal and in practical real world sense it's not significant enough. Their RE factor is basically identical 1.66 vs 1.6. The key for initiation is however detonation pressure and both in practical application max out around 300kbar or 30GPa. The limiting factor for ETN in commercial military application is low melting temp of 61C which means it is unlikely to withstand worst case storage or hot transport scenario in some desert environment without melting partially which precludes it from being used as base charge for caps or det cords. In practical terms, to get a capsule to 61C wouldn't be easy even leaving it out in a hot scortches sun, as a car hood on a hot summer rarely exceeds 60C, but it's possible and therefore it limits its commercial application in mining or military use. Reasoning is that if your base charge melts even slightly and mixes with primary charge on top, it might no longer have a working/predictable cap. I suspect MHN had its run as a commercial run as a base charge with melting temp of 112C precisely because of that even though ETN has a more stable storage profile and safer sensitivity profile. I did a thermal test of leaving a piece of tubing on a hot sun and it never exceeded 40C, so getting it to 60C would require uniquely extreme and unfavorable storage conditions.

The sensitivity profile depends on ETN crystalline morphology with many variations matching PETN sensitivity in practical terms. The difference is negligible.

So as to commercial applicability PETN remains uncontested because of the high melting temperature. In case of penta-E shortage ETN can probably replace PETN viably when utilized in cooler environments. In case of extreme economic and production bottlnecks it can probably replace it for all environments as reaching 60C is actually very difficult and rare. With regulatory application precautions it can probably be used safely on a mass production scale.