polyadditiopolimerisoinnin

Polyadditiopolimerisointi, known in English as polyaddition or addition polymerization, is a polymerization reaction in which monomers add to one another in such a way that the resulting polymer contains all the atoms of the original monomers. This process typically involves the reaction of monomers with at least two functional groups that can react with each other to form a larger molecule. Unlike condensation polymerization, no small molecules like water or alcohol are eliminated during the process.

The mechanism of polyaddition polymerization often proceeds through a chain-growth mechanism, where an active center on a growing polymer chain initiates the addition of successive monomers. This active center can be a free radical, an anion, or a cation. The reaction continues by adding monomers to this active site until a termination step occurs. Alternatively, polyaddition can also occur through a step-growth mechanism, where monomers react with each other to form dimers, trimers, and eventually longer chains, with each step involving the reaction of functional groups.

Common examples of polymers formed by polyaddition include polyurethanes, which are formed from the reaction of diisocyanates and diols, and epoxy resins, created by the reaction of epoxides with amines or other curing agents. The versatility of polyaddition allows for the synthesis of a wide range of materials with diverse properties, making it a significant process in polymer chemistry and material science. The rate of polymerization and the molecular weight of the resulting polymer are influenced by factors such as temperature, monomer concentration, and the presence of catalysts or initiators.