Polycondensation

This type of polymerisation generally involves repetitive condensation between two bifunctional monomers. Polycondensation results in loss of simple molecules like water, alcohol etc, and lead to formation of high molecular weight polymers. Here the product formed is also bifunctional species and the sequence of condensation goes on. Each step forms a distinct bifunctional species and each species is independent of each other, thus this process is also called step growth polymerisation.

The formation of PET/ Terylene/ Dacron occurs by this type of polymerisation.

Formation of PET

Polymerisation mechanism

Step growth process proceeds via stepwise reaction between the funtional group of reactants. The size of polymer increases at a relatively slow pace in condensation polymerisation.

One proceeds from monomer to dimer, trimer, tetramer, pentamer and so on until eventually a large sized polymer is formed.

Polycondensation.

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Polymers

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