Lahupolümerisatsioon

Lahupolümerisatsioon, also known as ring-opening polymerization (ROP), is a type of chain-growth polymerization process where cyclic monomers undergo polymerization through the cleavage of a ring bond. Unlike addition polymerization where monomers add to a growing chain without the loss of any atoms, ROP involves the opening of the cyclic structure of the monomer to form a linear polymer chain. This process typically requires initiation by a species that can abstract an atom or group from the ring or directly attack the ring itself.

ROP can be initiated by various mechanisms, including cationic, anionic, and radical pathways, as well as coordination-insertion mechanisms. The choice of initiator and monomer dictates the type of ROP and the resulting polymer structure. For example, cationic ROP is often used for monomers like epoxides and oxetanes, while anionic ROP is suitable for lactones and cyclic siloxanes. Coordination-insertion polymerization is a significant method for polymerizing cyclic olefins and lactones, often employing transition metal catalysts.

This polymerization technique is versatile and allows for the synthesis of a wide range of polymers with controlled molecular weights and architectures. Polymers produced via ROP find applications in diverse fields, including biodegradable materials, drug delivery systems, coatings, and advanced functional materials. The ability to control stereochemistry and produce polymers with specific end-groups makes ROP a valuable tool in polymer synthesis.