Additiopolymerytymisessä

Additiopolymerytymisessä refers to a process in polymer chemistry. It describes the formation of polymers through an addition reaction mechanism. In this type of polymerization, monomers add to one another in a way that the repeating unit in the polymer has the same atoms as the repeating unit in the monomer. There are no small molecules, such as water or ammonia, eliminated during the polymerization process. This distinguishes addition polymerization from condensation polymerization.

Common types of addition polymerization include free radical polymerization, cationic polymerization, and anionic polymerization. Each of these mechanisms involves the initiation, propagation, and termination steps. Initiation involves the formation of an active center, such as a radical or ion, which then reacts with a monomer to start the chain growth. Propagation is the process where the active center adds successive monomer units to the growing polymer chain. Termination occurs when the active center is deactivated, ending the growth of the polymer chain.

Many important synthetic polymers are produced by addition polymerization. Examples include polyethylene, polypropylene, polyvinyl chloride (PVC), and polystyrene. The control over molecular weight and polymer architecture can be achieved by varying reaction conditions, initiator type, and monomer concentration. The simplicity of the repeating unit structure, mirroring the monomer, is a key characteristic of polymers formed via addition polymerization.