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ChemicalBook CAS DataBase List Thiourea
62-56-6

Thiourea synthesis

1synthesis methods
Thiourea is manufactured by heating ammonium thiocyanate at 140-145°C for about 4 hours; equilibrium is established when about 25% of the thiocyanate is converted to thiourea.Thiourea may also be prepared by the interaction of cyanamide and hydrogen sulphide:

Thiourea closely resembles urea in that reaction with formaldehyde gives methylol derivatives and then resinous condensates which on continued heating yield network structures. Thiourea-formaldehyde resins are slower curing than urea-formaldehyde resins and the hardened products are more brittle and more water-resistant. At one time thiourea-formaldehyde resins were added to urea-formaldehyde resins to give mouldings and laminates with improved water-resistance. These mixed resins have now been largely superseded by melamine-formaldehyde resins which give products with better resistance to heat.
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Yield:-

Reaction Conditions:

with ammonia

References:

Sontakke, Madhuri M.;Jichkar, Atul A.;Dhonde, Madhukar G.;Bhaskar, Chandrakant S.;Berad, Baliram N. [Synthetic Communications,2014,vol. 44,# 3,p. 340 - 345] Location in patent:supporting information

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