Amino resins.

Amino resins

Amino resins are condensation products obtained by reaction of formaldehyde with nitrogen bearing compounds such as aniline, amides. For example urea formaldehyde, melamine formaldehyde.
Urea formaldehyde is prepared by condensation reaction between urea and formaldehyde in acidic or alkaline medium.
The first product formed during the formation of resin is monomethylol and dimethylol ureas.

Synthesis of amino resins step 1.
Polymerisation can take place from mono or di methylol urea or possibly through both with the formation of long chain.

Synthesis of amino resins step 2
The formation of melamine formaldehyde resin is similar to formation of urea formaldehyde.
Amino resins are clear and colourless.
They are harder and have high strength but lower heat and moisture resistance than phenolics.
The melamine formaldehyde resins have high moisture, heat and ageing resistance than urea formaldehyde resins but are usually costly.
Both urea formaldehyde and melamine formaldehyde resins are used as adhesives.
Amino resins are also used as coatings and laminates. Next

Uses of amino resins.

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Polymers

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