Polymerization is the synthesis of a polymer from monomer reactants. Crosslinking is the chemical linking of oligomers or polymers to produce large polymers or polymeric networks. (RDC 4/24/2009) 

“Polymerization is the process of combining many small molecules known as monomers into a covalently bonded chain. During the polymerization process, some chemical groups may be lost from each monomer. This is the case, for example, in the polymerization of PET polyester. The monomers are terephthalic acid (HOOC-C6H4-COOH) and ethylene glycol (HO-CH2-CH2-OH) but the repeating unit is -OC-C6H4-COO-CH2-CH2-O-, which corresponds to the combination of the two monomers with the loss of two water molecules. The distinct piece of each monomer that is incorporated into the polymer is known as a repeat unit or monomer residue.” (Wikipedia, Polymers, 5/27/2011)

“Two classes of polymerization usually are distinguished. In condensation polymerization, each step of the process is accompanied by formation of a molecule of some simple compound, often water. In addition polymerization, monomers react to form a polymer without the formation of by-products. Addition polymerizations usually are carried out in the presence of catalysts, which in certain cases exert control over structural details that have important effects on the properties of the polymer.”

“Linear polymers, which are composed of chainlike molecules, may be viscous liquids or solids with varying degrees of crystallinity; a number of them can be dissolved in certain liquids, and they soften or melt upon heating. Cross-linked polymers, in which the molecular structure is a network, are thermosetting resins (i.e., they form under the influence of heat but, once formed, do not melt or soften upon reheating) that do not dissolve in solvents. Both linear and cross-linked polymers can be made by either addition or condensation polymerization.”

(Britannica, Polymerization, 5/27/2011)

Electropolymerization
Precipitation Polymerization
Polymerization with Azides
Supercritical Carbon Dioxide Polymerization
Synthesizing Block Copolymers    
Synthesizing Chemical Libraries   
Synthesizing Polyrotaxanes   
Synthesizing Star Copolymers

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