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• Abu Asim

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Aniline Formaldehyde Resins

A family of thermoplastics synthesized by condensing aniline and formaldehyde in an acid solution exhibiting high dielectric strength.

Aniline

Aniline, phenylamine or aminobenzene is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the prototypical aromatic amine.

Uses of Aniline: Its main use is in the manufacture of precursors to polyurethane. Like most volatile amines, it possesses the

somewhat unpleasant odour of rotten fish. It ignites readily, burning with a smoky flame.

characteristic of aromatic compounds. Aniline is colorless, but it slowly oxidizes and resinifies in air, giving a red-brown tint to aged samples. Applications of Aniline: The largest application of aniline is for the preparation of methylene diphenyl diisocyanate.Aniline is predominantly used as a chemical intermediate for the dye, agricultural, polymer, and rubber industries. It is also used as a solvent, and has been used as an antiknock compound for gasolines. The principal use of aniline in the dye industry is as a precursor to indigo, the blue of blue jeansThe great commercial value of aniline was due to the readiness with which it yields, directly or indirectly, dyestuffsAniline is toxic by inhalation of the vapo The early manufacture of aniline resulted in increased incidents of bladder cancer, but these effects are now attributed to naphthylamines, not anilines.

Formaldehyde Formaldehyde (systematic name: methanal) is an organic compound with the formula CH2O. ). Formaldehyde is a good electrophile, participating in electrophilic aromatic substitution reactions with aromatic compounds, and can undergo electrophilic addition reactions with alkenes and aromatics. Formaldehyde undergoes a Cannizzaro reaction in the presence of basic catalysts to produce formic acid and methanol.

Formaldehyde kills most bacteria, and so a solution of formaldehyde in water is commonly used as a disinfectant. An aqueous solution of formaldehyde can be useful as a disinfectant as it kills most bacteria and fungi (including their spores). Formaldehyde solutions are applied topically in medicine to dry the skin, such as in the treatment of warts.

DISADVANTAGES OF FORMALDEHYDE When formaldehyde is present in the air at levels exceeding 0.1 ppm, some individuals may experience adverse effects such as watery eyes; burning sensations in the eyes, nose, and throat; coughing; wheezing; nausea; and skin irritation. Some people are very sensitive to formaldehyde, whereas others have no reaction to the same level of exposure

Why we use formaldehyde? Formaldehyde is a highly reactive, cell-permeable agent that is used by researchers as a reversible protein and nucleic acid crosslinking agent that couples primary amines that are within proximity of each formaldehyde molecule. Cell permeability allows the reagent to readily enter living cells enabling intracellular applications, such as protein interaction discovery or bioimaging. Formaldehyde crosslinks can be reversed simply by heating the sample.