Radikaalpolümeriseerumine

Radikaalpolümeriseerumine, also known as free-radical polymerization, is a common method for synthesizing polymers. It involves a chain reaction initiated by free radicals. These radicals are highly reactive species with an unpaired electron. The process typically begins with an initiator molecule that decomposes, often under heat or light, to generate these free radicals.

Once formed, the initiator radical attacks a monomer molecule, adding to its double bond and creating a new radical species on the monomer. This new radical then propagates by reacting with another monomer, extending the polymer chain. This chain growth continues as more monomers are added. The process is terminated when two growing radical chains combine, or when a disproportionation reaction occurs, leading to the formation of stable, non-radical polymer chains.

Radikaalpolümeriseerumine can be carried out in various ways, including bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization, each offering different advantages in terms of heat dissipation and product form. It is widely used to produce polymers such as polyethylene, polystyrene, and polyvinyl chloride. The control over molecular weight and polymer architecture can be influenced by factors like initiator concentration, monomer concentration, and temperature.