Synthetic techniques chain-growth polymerization

Life as we know it would not be possible without polymers. About 230 million tons were produced worldwide in 2009. The reader interested in the history of polymers will find a good overview in the book of Morawetz. Synthetic polymers are prepared from low molecular weight monomers by a process called polymerization, which can be divided from a mechanistic point of view into several classes. Amongst the most important polymerization techniques is radical polymerization which belongs to the class of chain-growth polymerizations. 

Two primary methods are commonly used to convert monomers into synthetic polymers. In the older literature, these techniques are referred to as addition and condensation polymerization, but because of ambiguities in these terms, the preferred names now are chain-reaction polymerization and step-growth... 

Biomacromolecules such as proteins derive their function from their three-dimensional shape and the precise functional group placement on the surface and interior of the structure. Also known as the tertiary structure, this shape is a result of a perfectly controlled monomer sequence, or primary structure. Synthetic polymers containing a perfect monomer sequence are inaccessible using contemporary techniques. However, recent advances in polymerization techniques allow for the fabrication of multi-block polymers with narrow molecular weight distributions " and materials with relatively controlled monomer sequences by step-growth and chain-growth... 

Abstract Polymers are macromolecules derived by the combination of one or more chemical units (monomers) that repeat themselves along the molecule. The lUPAC Gold Book defines a polymer as A molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. Several ways of classification can be adopted depending on their source (natural and synthetic), their structure (linear, branched and crosslinked), the polymerization mechanism (step-growth and chain polymers) and molecular forces (Elastomers, fibres, thermoplastic and thermosetting polymers). In this chapter, the molecular mechanisms and kinetic of polymer formation reactions were explored and particular attention was devoted to the main polymerization techniques. Finally, an overview of the most employed synthetic materials in biomedical field is performed. 

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