Ring-opening metathesis polymerization techniques

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 ... 

A drawback to the Durham method for the synthesis of polyacetylene is the necessity of elimination of a relatively large molecule during conversion. This can be overcome by the inclusion of strained rings into the precursor polymer stmcture. This technique was developed in the investigation of the ring-opening metathesis polymerization (ROMP) of benzvalene as shown in equation 3 (31). 

Besides the polymerization techniques discussed above, other polymerization methods have been used for the preparation of surface grafts. Recently, ring-opening metathesis polymerization (ROMP) became popular. This polymerization type will be discussed by Buchmeiser in Chapter 8. Recently, interesting accounts have appeared on solventiess polymerization techniques applying (living) ROMP on surfaces to prepare structured brush surfaces of conjugated polymers [331, 332]. 

Moore, J. S. Transition Metals in Polymer Synthesis Ring-opening Metathesis Polymerization and Other Transition Metal Polymerization Techniques. In Comprehensive Organometaltic Chemistry // Abel, E. W., Stone, F. G. A., Wilkinson, G., Eds. Elsevier Oxford, 1995 Vol. 12, pp 1209-1232. 

Polymers using the ring opening metathesis polymerization (ROMP) technique were first obtained at 1960 by Eleuterio (1,2). The patents deal with the polymerization of bicyclo[2.2.1]heptene-2, i.e., nor-bomene using a molybdenum catalyst dispersed on alumina. 

The ring-opening metathesis polymerization of dicyclopentadiene was monitored by ultrasonic spectroscopy.16 The thermoset poly(dicyclopentadiene) is formed by ringopening and cross-linking in a reaction injection molding system. A reaction cell with a plastic window was constructed for use with pulse echo ultrasonic spectroscopy. Realtime measurements of density, longitudinal velocity, acoustic modulus and attenuation were monitored. Reaction kinetics were successfully determined and monitored using this technique. 

Ring opening metathesis polymerization (ROMP) has proven to be a convenient technique that allows us to synthesize a wide variety of SCLCPs [8]. 

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. 

Scheme 7.36 Synthetic scheme for the polymerization of norbornene and its derivatives via free radical polymerization (FRP), ring-opening metathesis polymerization (ROMP), and vinyl addition polymerization (VAP) techniques. Polymers I, II, and III are isomers that differ in their enchainment and physical properties. Co- and terpolymerization of norbornene and derivatives of norbornene with other alicyclic monomers such as maleic anhydride, methyltetracyclododecene carboxylic acid, etc. are also successfully synthesized with this scheme. (Note that 2, 3- and 2,7-enchainments of repeating units are reported in type I polymers. °°)...

Each strategy involves various polymerization techniques, such as conventional and controlled radical polymerizations (CRPs), anionic polymerization, ring-opening metathesis polymerization (ROMP), and cationic polymerization. A judicious combination of a synthetic strategy and a polymerization technique can facilitate the preferential control of certain structural parameters, and this demonstrates distinct advantages with respect to the molecular design, as well as... 

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