Polüadditsioonis

Polüadditsioon is a type of polymerization reaction where monomers add to one another in a way that creates a chain without the loss of any atoms. This means that the repeating unit in the polymer has the same atoms as the monomers that formed it. Unlike condensation polymerization, where a small molecule like water or HCl is eliminated, polüadditsioon reactions involve the direct joining of monomer units.

These reactions typically occur between monomers that have functional groups capable of reacting with each other to form new covalent bonds. Common examples include the addition of monomers with double or triple bonds, or reactions between functional groups such as isocyanates and alcohols, or epoxides and amines. The process often involves a chain reaction mechanism, which can be initiated by a catalyst, heat, or light.

Polüadditsioon polymers are known for their unique properties, which depend on the specific monomers used. Many important industrial polymers are synthesized through polüadditsioon. For instance, polyurethanes are formed by the reaction of diisocyanates with diols, and epoxy resins are created by the reaction of epoxides with amines or anhydrides. The absence of eliminated byproducts often leads to polymers with high molecular weights and excellent mechanical properties. The control over the reaction conditions allows for tailoring the polymer structure and its resulting characteristics.