Paraformaldehyde
Names | |
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IUPAC name
Polyoxymethylene
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Identifiers | |
ChemSpider |
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ECHA InfoCard
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100.108.270 |
EC Number |
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UNII | |
UN number | 2213 |
CompTox Dashboard (EPA)
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Properties | |
OH(CH2O)nH (n = 8 - 100) | |
Appearance | White powder with formaldehyde-like odour |
Density | 1.46 g/cm3 |
Melting point | 120 °C (248 °F; 393 K) |
slightly soluble | |
Vapor pressure | 1.579 kPa |
Hazards | |
GHS labelling:[1] | |
Danger | |
H228, H302, H315, H317, H318, H332, H334, H351 | |
NFPA 704 (fire diamond) | |
Flash point | 71 °C (160 °F; 344 K) |
300 °C (572 °F; 573 K) | |
Explosive limits
|
7.0% (low), 73% (high) |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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800 mg/kg (rat, oral) |
LC50 (median concentration)
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1070 mg/m3 (rat, 4h) |
Safety data sheet (SDS) | Fisher Scientific |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Paraformaldehyde (PFA) is the smallest
Synthesis
Paraformaldehyde forms slowly in aqueous
Reactions
Paraformaldehyde can be
The resulting formaldehyde gas from dry heating paraformaldehyde is flammable.
Uses
Once paraformaldehyde is depolymerized, the resulting formaldehyde may be used as a
Paraformaldehyde is not a fixative; it must be depolymerized to formaldehyde in solution. In cell culture, a typical formaldehyde fixing procedure would involve using a 4% formaldehyde solution in
Paraformaldehyde is also used to crosslink proteins to DNA, as used in ChIP (chromatin immunoprecipitation) which is a technique to determine which part of DNA certain proteins are binding to.
Paraformaldehyde can be used as a substitute of aqueous formaldehyde to produce the resinous binding material, which is commonly used together with melamine, phenol or other reactive agents in the manufacturing of particle board, medium density fiberboard and plywood.[4]
Toxicity
As a formaldehyde releasing agent, paraformaldehyde is a potential carcinogen.[5] Its acute oral median lethal dose in rats is 592 mg/kg.[6]
See also
- 1,3,5-Trioxane (metaformaldehyde), the cyclic trimer of formaldehyde
References
- ^ "C&L Inventory". echa.europa.eu. Retrieved 27 December 2021.
- .
- ^ "Be Wary of Sargenti Root Canal Treatment | Quackwatch". May 2018.
- ^ "Paraformaldehyde - Dover Chemical".
- PMID 15384217.
- ^ "MSDS - 158127 SAFETY DATA SHEET - Paraformaldehyde". SIGMA-ALDRICH. Retrieved 15 February 2022.