Ring-opening metathesis polymerization utility

In addition to the design of the solubility properties, the reactivity of organome-tallic species toward CO2 [13] (and many other potential supercritical reaction media) must be considered as important criteria for the choice of the catalyst. For example, the bisallyl ruthenium complex shown in Table 1 cannot be utilized as a precursor for ring-opening metathesis polymerization (ROMP) in SCCO2, because the insertion of CO2 into the Ru-allyl bond prevents the initiation mechanism [14]. Metal-mediated oxygen transfer to form CO and phosphine oxide was found to lead to deactivation of the [Ni(cod)2]/PMe3 (cod = 1,5-m-cycloocta-diene) catalyst system [15]. On the other hand, the reactivity of CO2 with metal... 

Dense carbon dioxide represents an excellent alternative reaction medium for a variety of polymerization processes. Numerous studies have confirmed that CO2 is a potential solvent for many chain growth polymerization methods, including free-radical, cationic, and ring-opening metathesis polymerizations. Carbon dioxide has also been demonstrated to be an effective solvent for step-growth polymerization techniques. Advances in the design and synthesis of surfactants for use in CO2 will allow compressed CO2 to be utilized for a wide variety of polymerization systems. These advances may enable carbon dioxide to replace hazardous VOCs and CFCs in many industrial applications, making CO2 an enviromentally responsible solvent of choice for the polymer industry. 

This was utilized to form several novel homopolymers with l,2-bis(3-thienyl)cyclopentene derivatives using ring-opening metathesis polymerization techniques. The color forming cyclization reaction in the polymers can be illustrated as follow ... 

Ring-Opening Metathesis Polymerization 21.2.7.1. Utility of Ring-Opening Metathesis Polymerization... 

Vinylene-bridged [2]ferrocenophanes [35] or diene-bridged [4]ferrocenophanes [36] have been utilized as monomers in a ring-opening metathesis polymerization by the use of molybdenum catalysts (Fig. 8.10). 

Olefin metathesis has been of interest both industrially and academically because of its great synthetic utility (4). Mechanistically related metathesis reactions include ring opening metathesis (ROM), ring-closing metathesis (ROM), cross-metathesis (CM), acyclic diene metathesis (ADMET) polymerization, and ring-opening metathesis polymerization (ROMP) (Fig. 12) (5-8,390,391). 

This chapter intends to give a brief overview over the ROMP of some selected cycloolefins to demonstrate the great utility of ring-opening metathesis polymerization. 

Nomura K. Precise synthesis of amphiphilie polymeric nano architectures utilized by metal-catalyzed hving ring-opening metathesis polymerization (ROMP). In Rizzo M, Bruno G, editors. Surface Coatings. New York Nova Science Pubhshers 2009. p 123-152. 

Now that you know more about polymers, we can apply some of the concepts you ve learned to ring-opening metathesis polymerization (ROMP), a polymerization reaction that utilizes the metathesis reaction introduced at the beginning of the chapter. The general mechanism for ROMP is as follows ... 

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