Paraformaldehyde

What is Paraformaldehyde?

A polymer of formaldehyde known as polyoxymethylene is called paraformaldehyde. It is the smallest polyoxymethylene, typically polymerizing to a degree of 8 to 100 units. Paraformaldehyde is used to produce resins, polymers, and adhesives as well as a fixative for histology and microscopy.

Paraformaldehyde Characteristics

Appearance: solid white crystals
Density at 25 °C: 1.42 g/cm3
Water solubility: Low Odor: As a result of decomposition, paraformaldehyde frequently has a faint formaldehyde odor.
With a normal degree of polymerization of 8–100 units, paraformaldehyde is the smallest polyoxymethylene and the polymerization product of formaldehyde.
Synthesis: When stored in the cold, paraformaldehyde will slowly form as a white precipitate in aqueous formaldehyde solutions. Actually, the majority of the formalin forms short chains of polyformaldehyde; it contains very little monomeric formaldehyde. As a stabilizer, methanol is frequently added in modest amounts to help reduce the degree of polymerization.
Depolymerization: When heated dry, paraformaldehyde can be converted to formaldehyde gas, and when water is added in the presence of a base, an acid, or heat, it can be converted to formaldehyde solution. Dry heating paraformaldehyde produces flammable formaldehyde gas

Uses: Paraformaldehyde has a variety of uses, including as a fixative for microscopy and histology, for crosslinking proteins to DNA, as a source of formaldehyde groups in the production of many thermosetting resins, together with phenol, urea, and other reactive agents, as a substitute for aqueous formaldehyde in the production of resinous binding material, commonly used with melamine, phenol, or other reactive agents in.
Risks: Because paraformaldehyde may cause cancer, it should be handled carefully. It can react violently with strong oxidizing agents, bases, and nitrogen dioxide and is flammable.