Isobutylidenediurea (abbreviated IBDU) is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula (CH₃)₂CHCH₂. It is a derivative of urea (OC(NH₂)₂), which itself is highly soluble in water, but IBDU is not. It functions as a controlled-release fertiliser owing to its low solubility, which limits the rate of its

hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water ...

to urea, which is a fast-acting fertiliser. It is produced by the

condensation reaction In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a ...

isobutyraldehyde Isobutyraldehyde is the chemical compound with the formula (CH3)2CHCHO. It is an aldehyde, isomeric with ''n''-butyraldehyde (butanal). Isobutyraldehyde is made, often as a side-product, by the hydroformylation of propene. Its odour is described ...

and two equivalents of urea: : (CH₃)₂CHCHO + 2 OC(NH₂)₂ → (CH₃)₂CHCH₂ + H₂O The controlled-release process is the reverse of the above reaction, which only occurs after the IBDU dissolves.

Related materials

A number of CRF's have been developed based on urea. Related to IBDU is crotonylidene diurea (Crotodur). Simpler are various urea-formaldehyde materials such as ureaform, which consists of

methylene diurea Methylene diurea (MDU) is the organic compound with the formula CH2(NHC(O)NH2)2. It is a white water-soluble solid. The compound is formed by the condensation reaction, condensation of formaldehyde with urea. Methylene diurea is the substrate fo ...

and

dimethylene triurea Dimethylene triurea (DMTU) is the organic compound with the formula (H2NC(O)NHCH2NH)2CO. It is a white water-soluble solid. The compound is formed by the condensation of formaldehyde with urea. Both branched and linear isomers exist. Application ...

.{{Ullmann, doi= 10.1002/14356007.n10_n01 , title= Fertilizers, 2. Types , year=2009 , last1=Dittmar , first1=Heinrich , last2=Drach , first2=Manfred , last3=Vosskamp , first3=Ralf , last4=Trenkel , first4=Martin E. , last5=Gutser , first5=Reinhold , last6=Steffens , first6=Günter

References

Ureas Soil improvers Fertilizers