Condensation reaction

Mechanism

Many condensation reactions follow a single electron transfer conditions.

The synthesis of polymers, where monomers react and become covalently bonded with one another through the loss of a water molecule.

Condensation reactions in polymer chemistry

In polymer chemistry, a series of condensation reactions take place whereby monomers or monomer chains add to each other to form longer chains. This may also be termed as 'condensation polymerization' or 'step-growth polymerization'. It occurs either as a homopolymerization of an A-B monomer or a polymerization of two co-monomers A-A and B-B. Small molecule condensates are usually liberated, unlike in polyaddition where there is no liberation of small molecules.

A high conversion rate is required to achieve high molecular weights as per Carothers' equation.

In general, condensation polymers form more slowly than addition polymers, often requiring heat. They are generally lower in molecular weight. Monomers are consumed early in the reaction; the terminal functional groups remain active throughout and short chains combine to form longer chains. Bifunctional monomers lead to linear chains (and therefore thermoplastic polymers), but when the monomer functionality exceeds two, the product is a thermoset polymer.

Applications

This type of reaction is used as a basis for the making of many important benzoin condensation.

Many biological transformations are condensation reactions. glycosylations are a few examples.

References

1. ^ International Union of Pure and Applied Chemistry (1994). "Condensation Reaction". Compendium of Chemical Terminology Internet edition.