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Initiation in Anionic Chain-Growth Polymerization

المؤلف:  A. Ravve

المصدر:  Principles of Polymer Chemistry

الجزء والصفحة:  182

2026-01-18

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Initiation in Anionic Chain-Growth Polymerization

Anionic initiations can take different paths. That depends upon the initiator, the monomer, and the solvent [143]. As a rough generalization, however, it is possible to separate the initiation reactions into two types: (1) those that take place through an addition of a negative ion to an olefin, and (2) those that result from an electron transfer. The polymerization reactions can, furthermore, occur in two ways. One way is in a homogeneous environment, with both monomer and initiator soluble in the solvent. The other way is in a heterogeneous one, where only the monomer is soluble. Organolithium compounds are examples of soluble initiators, while metal dispersions are examples of insoluble ones. The homogeneous polymerizations can be separated further into those carried out in non-polar solvents and those in polar ones. In non-polar solvents they are confined mostly to organolithium initiators. Other organometallic compounds require polar solvents for solubility.