Para formaldehyde

(PFA) is the smallest polyoxymethylene, the polymerization product of formaldehyde with a typical degree of polymerization of 8–100 units. Paraformaldehyde commonly has a slight odor of formaldehyde due to decomposition. Paraformaldehyde is a poly-acetal.

Paraformaldehyde can be depolymerized to formaldehyde gas by dry heating and to form a formaldehyde solution by water in the presence of a base or heat. The very pure formaldehyde solutions obtained in this way are used as a fixative for microscopy and histology.

The resulting formaldehyde gas from dry heating paraformaldehyde is flammable.

Specification :

  • Chemical formula : OH(CH2O)nH (n = 8 - 100)
  • Appearance : Powder
  • Physical State : Solid
  • Solubility : Soluble in hot water, and many organic solvents. Insoluble in water
  • Storage : Store at 4°C
  • Melting Point : 120-170 °C (lit.)
  • Density : 0.88 g/cm3 at 25 °C (lit.)

Uses :

  • Formalin fixative to fix cells and tissues
  • Uses as a disinfectant, fungicide, fixation reagent
  • Uses in the preparation of formaldehyde
  • Fixative in electron microscopy