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Ring-opening metathesis polymerization (ROMP) is a type of olefin metathesis chain-growth polymerization that produces industrially important products. The driving force of the reaction is relief of ring strain in cyclic olefins (e.g. norbornene or cyclopentene) and a wide variety of catalysts have been discovered. Research has shown that the addition of substituents to the monomer and the choice of solvent can alter the molecular weight of the polymer produced. ==Mechanism== The catalysts used in the ROMP reaction include a wide variety of metals and range from a simple RuCl3/alcohol mixture to Grubbs' catalyst The ROMP reaction is catalyzed primarily through the formation of metal-carbene complexes as first reported by Nobel Prize winner Yves Chauvin and his colleague Jean-Louis Hérisson although a hydride mechanism has also been reported.〔 The initiation of the carbene species occurs through numerous pathways; solvent interactions, substituent interactions, and co-catalysts all can contribute to the production of the reactive catalytic species〔 . The ROMP catalytic cycle requires a strained cyclic structure because the driving force of the reaction is relief of ring strain. After formation of the metal-carbene species, the carbene attacks the double bond in the ring structure forming a highly strained metallacyclobutane intermediate. The ring then opens giving the beginning of the polymer: a linear chain double bonded to the metal with a terminal double bond as well. The new carbene reacts with the double bond on the next monomer, thus propagating the reaction〔 : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ring-opening metathesis polymerisation」の詳細全文を読む スポンサード リンク
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