Macromolecules, polymerizations

This article is an attempt to review possibilities in a quantum chemical treatment of open-shell systems. In order to cut down the extent of this review, we disregard some problems, especially those concerning macromolecules, polymerization reactions, and open-shell transition-metal complexes. Electron spin resonance is mentioned only briefly, because it has been a topic of many reviews. 

On this basis, five classes of different polyphosphazenes are considered as outstanding examples of this type of macromolecules, in which skeletal and substituent features overlap to the highest extent. The reported materials are elastomers, flame retardants and self-extinguishing macromolecules, polymeric ionic conductors, biomaterials, and photosensitive polymeric compounds all of them based on the polyphosphazene structure. 

Know the meaning of monomer, polymer, macromolecule, polymerization, average molecular weight. 

The modem concept of linear polymers was introduced in 1920 by Staudinger, who fully recognized the idea of chain addition reaction yielding long molecules composed of monomeric units linked by covalent bonds. He was also the first to understand the anionic character of formaldehyde polymerization initiated by bases such as sodium methoxide4. In fact, studies of this reaction led him to the notion of linear macromolecules. Polymerization of ethylene oxide initiated by alkali metals and reported as early as 18785 could also be interpreted in these terms. 

Comprehensive Polymer Science was published in 1989 as a set of seven volumes and then supplemented by two additional volumes. This excellent print collection comprehensively covered the entire field of polymer science at that time. Much of the information is currently still as valuable as it was then, although some aspects are seen differently now. Those differences are important in order to understand the enormous development polymer science has taken since 1989. When we developed the concept for an entirely new edition of Polymer Science A Comprehensive Reference, we intended not only to update and replace the original edition of Comprehensive Polymer Science, (we are pleased to announce that it will be soon available in electronic format) but also to focus on a widely observed transition of polymer science, from exploring only macromolecules, polymeric materials, and polymerization processes to become part of a comprehensive study on molecular soft matter science enabling advancements in other related disciplines. 

Very fast reaction times are needed to complete macromolecule polymerization. 

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