OP-2 (thickener)

OP-2 (ОП-2), or Ionov's salt, is a chemical substance used as a standard gasoline thickener by the Soviet Union and Russia.[1][2] The main component of OP-2 gel is gasoline. It's the Soviet equivalent of napalm, developed at the beginning of World War II.[3]
Effect
Contact with the lit material causes deep burns, due to the retarding effect of the thickener on the fuel and due to the greater thermal conduction given by the salt. It is an incendiary agent with anti-personnel and limited anti-material effect. It is used as a defoliant to deprive enemy personnel of cover and camouflage.[4]
Use

The use of the OP-2 is identical to that of napalm, being used extensively by any projector of incendiary material. The employment concentration is identical to that of napalm.[5]
Precursor used to obtain incendiary weapons, it is the standard flame fuel thickener of the soviet union.[6] It was first employed by the soviet union during the early part of world war II to prepare flamethrower fuel[7] (ROKS-3 and LPO-50),[8][9] molotov cocktail,[10] general incendiary weaponry.[11] It continues to be employed by the Russian army. For example, it is used to prepare the AP-10, which fills the ZB-500 incendiary shell.[4] The OP-2 was supplied to states aligned with the soviet union.[6][12]
Composition
OP-2 is an aluminum salt of petroleum acid derivatives. The OP-2 and gasoline solution behaves like an unconventional fluid. Its non-stoichiometric formula is (RCOO)1.5Al(OH)1.5 (OP-2A).[13] OP-2 has approximately the same thickening capabilities as napalm, but much more compatible with other fuels, such as isooctane, and stable to aerial oxidation, but it is more rheologically unstable - this last point relates to the moisture pickup during the precipitate processing.[14][15][16] On the cardboard packaging of the OP-2, the inscription "H.A." refers to its unit component, aluminum naphthenate.[17]
History
The principle of a viscous incendiary weapon was first realized in the early Middle Ages in the form of Greek fire. In modern times, the first tests were carried out during the first world war in the form of solidified oil (SO), developed by CWS.[18] Gasoline and rubber mixtures were tested post-war and during the early stages of WWII. Rubber shortages, caused by the territorial expansion of imperial Japan, forced it to be replaced by synthetic materials.[19]
During the early stages of the WWII, Amfilogiy Pavlovich Ionov, under collaboration of Piotr Alexandrovich Rehbinder, in 1939, specialized aluminum naphthenate to be inserted into fuels in order to thicken them.[20][3] Their work was perfected by A. A. Trapeznikov and N. A. Bakh at the Institute of Physical Chemistry, Academy of Sciences of the USSR.[3] Industrial-scale production was established in 1941 by the Soviet government, with most soap-producing companies operating under contract.[21]

After Pearl Harbor, the CWS began hiring staff to investigate a natural rubber substitute in the United States. The end result of the investigation was a modified aluminum naphthenate called napalm, which was used to thicken thin fuels.[22][23]
Due to the same orders as the initials of its name, OP-2 was, for a long time, interpreted as being the opalm, a "hybrid" swiss thickener.[24] OP-2 was re-engineered into a new thickener, the NK, its successor.[25][26]
Vietnam War
The first documented use of the OP-2 was in May 1967 by the North Vietnamese army at Con Thien. In addition to this first use, it was used against U.S. troops at Kontum, Lang Vei, Quang Ngai, Bihn Dihn, and Loc Ninh.[6]
Preparation
The manufacture of aluminum soaps demands careful control over a multitude of variables.[27][15][28] Aluminum naphthenates require extra care in manufacturing conditions, due to their tendency to sinter.[14] Coagulation pH, residual moisture, reaction temperature, and reagent concentration are variables that have the greatest impact on the product's ability to modify fuel rheology.[28][15] The thickener obtained a satisfactory degree of thickening and stability when it was precipitated into a strongly alkaline aqueous medium.[15][27]
OP-2 is prepared under a caustic excess of 100% to prevent sintering of the amorphous solid and undesirable chemical reactions. A caustic excess of 75% is recommended for aluminum soaps in which the raw material has an average molecular weight of 214-250.[29] Unlike classical double ionic displacement reactions in aqueous medium,[30] the reaction product is an adsorption complex between organic acid and hydrated alumina,[31][32] a similar mechanism is also postulated for other aluminum soaps,[33] but they are not the only ones.[34][35][36] The general chemical reaction equation can be given as:[13]
See also
- Laghman massacre
- Napalm - A modified hydroxyaluminum naphthenate
- Geletrol
- F.R.A.S. - Aluminum hydroxydistearate based fuel
References
- ^ "Дымовые и огнеметно–зажигательные средства". rufort.info. Retrieved 2022-10-10.
- ^ Зажигательные средства дыма и огнеметы. А. Белоусов. pp 174-176.
- ^ a b c Soviet Work on Solidified Fuels: B. I. Losev; Solid Gasoline. Priroda, Vol 47, No 9.
- ^ a b "ЗБ-500". www.airwar.ru. Retrieved 2022-10-10.
- ^ Федосеев, Семен; Ардашев, Алексей (2022-04-16). Огнеметные танки и ручные огнеметы в бою (in Russian). Litres. ISBN 978-5-457-58982-7.
- ^ a b c ARMY. August 1968, 58-59
- ^ Lakin G. Sherril. (U) NVA TRAINING AND EMPLOYMENT OF FLAMETHROWERS. Report No. 6 029 0019 70. Jan 1970
- ^ "Огнем, водой и деревянными пулями: испытания советской винтовки-огнемета". kalashnikov.media (in Russian). Retrieved 2022-10-10.
- ^ SupR 66152. Section XIII - Flamethrower, Portable, LPO-50. 223
- ^ Tov_sergeantwrote, Tov_sergeant Tov_sergeant. "ПРО КОКТЕЙЛЬ МОЛОТОВА". tov-sergeant.livejournal.com. Retrieved 2022-10-10.
- ^ Михаил Барятинский. Т-54 и Т-55. «Танк-солдат»: TO-54
- ^ Captain James T. Parks. PORTABLE FLAME THROWER UNITS ORGANIC TO THE INFANTRY BRIGADE - ANNEX 3: The Portable Flame Thrower Use Against the American in Viet Nam by the North Vietnamese and the Viet Cong. Roster Number 121, Advisor Group 7, Advance 4. 25 September 1968
- ^ a b Корольченко А.Я., Корольченко Д.А. Пожаровзрывоопасность веществ и материалов и средства их тушения. Справочник в 2-х томах (in Russian).
- ^ a b Elliott, S. B. "The Preparation and Properties of Aluminum Naphthenate Soaps". apps.dtic.mil. Archived from the original on 2025-03-24. Retrieved 2025-05-03.
- ^ a b c d G. V. Belugina and A, A. Trapeznikov. Kolloid Zhurnal. 20 No. 1. 1-8. 1958
- ^ OSRD Report No. 425. May, 1943-December, 1944
- ^ Управление Начальника Химических Войск Сухопутных Войск Вооруженных Сил Ссср. Ранцевый огнемет РОКС-3 (1946) - Материальная Часть И Курс Огнеметания. ПОСОБИЕ ДЛЯ ОФИЦЕРСКОГО СОСТАВА. Moscow -1946.
- ^ AMOS A. FRIES and CLARENCE J. WEST. CHEMICAL WARFARE.New York: McGraw-Hill, 1921.
- ^ WAR DEPARTMENT - TECHNICAL MANUAL 3-330: INCENDIARY BOMBS. March 23, 1942
- ^ "ФОГи и РОКСы на службе в Красной Армии". Оружие и боеприпасы (in Russian). Retrieved 2025-06-30.
- ^ "ФОГи и РОКСы на службе в Красной Армии". Оружие и боеприпасы (in Russian). Retrieved 2025-11-25.
- ^ "Napalm, An American Biography". Napalm, An American Biography. Retrieved 2022-10-28.
- ^ Fieser, Louis F.; Harris, George C.; Hershberg, E. B.; Morgana, Morley; Novello, Frederick C.; Putnam, Stearns T. (1946-08-01). "Napalm". Industrial & Engineering Chemistry. 38 (8): 768–773. doi:10.1021/ie50440a010. ISSN 0019-7866.
- ^ Bochsler, Regula (28 January 2023). "Napalm from the Alps: How the Swiss developed a lethal incendiary agent". SWI swissinfo.ch. Retrieved 2023-01-28.
- ^ 世界军事年鉴 1987. p 551
- ^ NATIONAL UNIVERSITY OF CIVIL DEFENSE OF UKRAINE - DEPARTMENT OF VYYSKOV PREPARATION. Section 3. “TACTICAL AND TACTICAL-SPECIAL TRAINING.” TSP module 03.04. “Radiation, chemical and biological protection of birds.” Substitute module 2. “Radiation, chemical, biological protection of pesticides.” Lesson 1. “Meta, research and development of radiation, chemical, biological protection of animals.”
- ^ a b A. A. Trapeznikov, G.V. Belugina and F. M. Rzhavskaia. Kolloid Zhurnal. 20, 2. p 243-244. 1958.
- ^ a b Woods, D. E.; Taylor, A. J. (1958). "The preparation of aluminium soaps by a continuous process. I. Aluminium laurate". Journal of Applied Chemistry. 8 (4): 237–246. doi:10.1002/jctb.5010080408. ISSN 1934-998X.
- ^ "Г. В. Белугина, В. В. Константинова, С. Х. Закиева, П. А. Ребиндер, "Исследование гелеобразующей способности олеатов алюминия в бензоле", Докл. АН СССР, 132:2 (1960), 380–383". www.mathnet.ru. Retrieved 2025-07-17.
- ^ S. V. Pestrikov, N. V. Rodionova, A. A. Trapeznikov, and N. V.. Journal of Applied Chemistry of the USSR 1976-12: Vol 49, Iss 12-1. p 2612-2615.
- ^ D. F. Vasil'ev. Kolloid Zhurnal. 11. 377-383. 1949.
- ^ D. F. Vasil'ev. Kolloid Zhurnal. 20. 393-395, 4. 1958.
- ^ Rakowitz, D. H. Studies Of The Chemistry And Formation Of Certain Aluminum Soaps.[1] Columbia University ProQuest Dissertations & Theses, 1955. 0021814.
- ^ S. V., Pestrikov; N. V., Rodionova; A. A., Trapeznikov; N. V., P'yankova; Z. F., Kuz'mina. Kolloid Zhurnal. 39. 869-871, 3. 1977.
- ^ N. V., Rodionova; S. V., Pestrikov; A. A., Trapeznikov; N. V., P'yankova. Kolloid Zhurnal. 37. 536-539, 3. 1975.
- ^ Bulloff, Jack J. The Composition Of Aluminum Soaps. RPI - Troy, NY. April, 1953
Related works
- A, N, Ardashev. (2009). Зажигательное и огнеметное оружие. ISBN 978-5-699-33627-2
- Управление Начальника Химических Войск Сухопутных Войск Вооруженных Сил Ссср. Ранцевый огнемет РОКС-3 (1946) - Материальная Часть И Курс Огнеметания. ПОСОБИЕ ДЛЯ ОФИЦЕРСКОГО СОСТАВА. Moscow -1946.
- Rakowitz, D. H. Studies Of The Chemistry And Formation Of Certain Aluminum Soaps.[2] Columbia University ProQuest Dissertations & Theses, 1955. 0021814.
- Elliott, S. B.: OSRD Contract No. OEMsr-882. Ferro Drier & Chemical Co. January 3, 1944.[3]
- Broughton, G., and Byfield, A.: OSRD Report No. 2036, November 17, 1943.[4]
- Broughton, G., and Byfield, A.: OSRD Report No. 2036A, March 7, 1944.[5]
- McIntyre, G. H.; Elliott, S. B.: OSRD Report No. 3772. June, 1944.[6]
- Betts, R. L.: OSRD Report No. 4552. January, 1945.[7]
- Elliott, S. B.: OSRD Contract No. OEMsr-882. Ferro Drier & Chemical Co. January 3, 1944.[8]
- Dawson, R. D.; White, E. R.: OSRD Report No. 3506. Shell Development Co. April 20, 1944.[9]
- Jack. J. Bulloff. The Composition of Aluminum Soaps. Ph.D. Thesis. Rensselaer Polytechnic Institute. Troy, NY. April, 1953.
- Kirkpatrick, E. C.: OSRD Report No. 3507. E. I. Du Pont de Nemours and Company Ammonia Department. April 20, 1944.[10]
- Brock, G. C.; Orr, A. G.: OSRD Report No. 6237. California Research Corporation. September 29, 1945.[11]
- Kirkpatrick, E. C.: OSRD Report No. 4202. E. I. Du Pont de Nemours and Company Ammonia Department. October 2, 1944.[12]
- Kirkpatrick, E. C.: OSRD Report No. 3763. E. I. Du Pont de Nemours and Company Ammonia Department. June 10, 1944.[13]
- Broughton, G; Carver, E. K.: OSRD Report No. 1113. June 5, 1942 to December 1, 1942.[14]
- R. P. Russell.: OSRD Report No. 382. Standard Oil Development Company. February 7, 1942.[15]
- McBain, J. W.; OSRD Report No. 425. May, 1943-December, 1944. [16] [17]
- OFFICE OF SCIENTIFIC RESEARCH AND DEVELOPMENT WASHINGTON DC.: Fire Warfare, Incendiaries and Flame Throwers. 30/09/1946. [18]
External links
PAKISTAN: LEADER OF REBEL AFGHAN GROUP CLAIMS SOVIET TROOPS HAVE STRAFED VILLAGES AND DROPPED NAPALM BOMBS. (1980) (Film). Pathé News. 1980. VLVA4EBU0SGGUZ73ZAVPS88EW95S9.