Norbomenes copolymerization

Dicyclopentadiene is also polymerized with tungsten-based catalysts. Because the polymerization reaction produces heavily cross-Unked resins, the polymers are manufactured in a reaction injection mol ding (RIM) process, in which all catalyst components and resin modifiers are slurried in two batches of the monomer. The first batch contains the catalyst (a mixture of WCl and WOCl, nonylphenol, acetylacetone, additives, and fillers the second batch contains the co-catalyst (a combination of an alkyl aluminum compound and a Lewis base such as ether), antioxidants, and elastomeric fillers (qv) for better moldabihty (50). Mixing two Uquids in a mold results in a rapid polymerization reaction. Its rate is controlled by the ratio between the co-catalyst and the Lewis base. Depending on the catalyst composition, solidification time of the reaction mixture can vary from two seconds to an hour. Similar catalyst systems are used for polymerization of norbomene and for norbomene copolymerization with ethyhdenenorbomene. 

Poly(norbornene Sulfones) by Radical Polymerization. Cycloolefins such as norbomene copolymerize with SO2 in an alternating fashion by radical initiation at room temperature or even at 50 °C, reflecting their high ceiling temperatures (77). In order to avoid the use of a pressure bottle, however, we carried out the polymerization of norbomenes with SO2 at cryogenic temperatures. A partial list of poly(norbomene sulfones) we prepared is presented in Scheme V. All the polymers were prepared readily in high conversions but some of the polymers were not very soluble (pendant carboxylic acid, for example). This paper primarily discusses about the... 

A chain migratory insertion mechanism for ethylene/norbomene copolymerization utilizing both A and B coordination sites in an alternating fashion is implied by the derived parameter set... 

FIGURE 16.12 Palladium a-diimine catalysts used for ethylene/norbomene copolymerization (GLY = 1,2-ethanediimine = glycine-derivate BUD = 2,3-butanedirmine). 

Kiesewetter, J. and Kamindcy, W. (2003) Ethene/norbomene copolymerization with palladium(II) a-diimine catalysts From ligand screening to discrete catalyst species. Chemistry - A European Journal, 9,1750-1758. 

Bhriain et al. daim that GGTP occurs in ethylene-norbomene copolymerizations using metallocene 23 in combination with zinc or aluminum alkyls. The reversibility is indicated by a reduction in M and a modest narrowing of the distribution (1.6reversible chain transfer in ethylene polymerization using the hafiiium amidinate precatalyst 24 with DEZ, produdng mono-disperse PEs with Mn s up to 665 g mol". ... 

Figure 8 Zirconocene precatalysts for living ethylene/norbomene copolymerization.

Ethylene—Propylene Rubber. Ethylene and propjiene copolymerize to produce a wide range of elastomeric and thermoplastic products. Often a third monomer such dicyclopentadiene, hexadiene, or ethylene norbomene is incorporated at 2—12% into the polymer backbone and leads to the designation ethylene—propylene—diene monomer (EPDM) mbber (see Elastomers, synthetic-ethylene-propylene-diene rubber). The third monomer introduces sites of unsaturation that allow vulcanization by conventional sulfur cures. At high levels of third monomer it is possible to achieve cure rates that are equivalent to conventional mbbers such as SBR and PBD. Ethylene—propylene mbber (EPR) requires peroxide vulcanization. 

The resulting complexes can be effectively employed as single component catalysts to homopolymerize ethylene or copolymerize ethylene with acrylates [50, 51] and a variety of other polar monomers including vinyl ethers, [51,52] vinyl fluoride [53], iV-vinyl-2-pyrrolidinone, and AMsopropylacrylamide [54], In fact, the resulting catalysts are so robust that they can be used as single component catalysts in aqueous emulsion homo-polymerization of ethylene and copolymerization of ethylene with norbomenes and acylates [55]. 

The metathesis route opens up new opportunities for the synthesis of new copolymers by copolymerizing 6,7-dihydro-2(3//)-oxepinone with other cyclic olefins such as norbomene, even though this approach has barely been exploited until now [121]. 

Counterion effects similar to those in ionic chain copolymerizations of alkenes (Secs. 6-4a-2, 6-4b-2) are present. Thus, copolymerizations of cyclopentene and norbomene with rhenium- and ruthenium-based initiators yield copolymers very rich in norbomene, while a more reactive (less discriminating) tungsten-based initiator yields a copolymer with comparable amounts of the two comonomers [Ivin, 1987]. Monomer reactivity ratios are also sensitive to solvent and temperature. Polymer conformational effects on reactivity have been observed in NCA copolymerizations where the particular polymer chain conformation, which is usually solvent-dependent, results in different interactions with each monomer [Imanishi, 1984]. 

These requirements have met using a mixed catalystic system consisting of an iron catalyst complex that can oligomerize ethylene and a zirconium transition metal complex that can copolymerize ethylene and the nonconjugated monomer 5-ethylidene-2-norbomene. Using this catalytic pair nonbrancy poly(ethylene-co5-ethylidene-2-norbomene) and poly (ethylene-col,4-hexadiene) were prepared. 

Research Focus Ambient temperature copolymerization of ethylene with 5-norbomen-2-yl acetate or with ethylene and 5-norbomen-2-yl alcohol. 

Ethylene and 5-norbomen-2-yl-acetate were also copolymerized using N-(2,6-diisopropylphenyl)-2-(2,6-diisopropylphenylimino)propanamide-benzyltrimethyl-phosphine nickel. 

Norbomen-2-yl 4-(l-(3-(2,2,5-trimethyl-4-phenyl-3-azahexoxy))ethyl)ben-zyl ether, (V), was previously prepared by the authors (4) and used in the controlled free radical copolymerization of ethylene and 5-norbomen-2-ol. Polymerization were carried out in the presence of the two component catalyst mixture of the current application. 

T. Hasan, T. Ikeda, and T. Shiono, Homo- and copolymerization of norbomene derivatives with ethene by ansa-fluorenylamidodimeth-yltitanium activated with methylaluminoxane,. Polym. Sci., Part A Polym. Chem., 45(20) 4581-4587, October 2007. 

W. Wang and K. Nomura, Remarkable effects of aluminum cocatalyst and comonomer in ethylene copolymerizations catalyzed by (arylim-ido)(aryloxo) vanadium complexes efficient synthesis of high molecular weight ethylene/norbomene copolymer, Macromolecules, 38(14) 5905-5913, July 2005. 

G.M. Benedikt, E. Elce, B.L. Goodall, H.A. Kalamarides, L.H. McIntosh, L.F. Rhodes, K. Selvy, C. Andes, K. Oyler, and A. Sen, Copolymerization of ethene with norbomene derivatives using neutral nickel catalysts, Macromolecules, 35(24) 8978-8988, November 2002. 

W. Kaminsky, S. Derlin, and M. Hoff, Copolymerization of propylene and norbomene with different metallocene catalysts, Polymer, 48(25) 7271-7278, November 2007. 

J. Kiesewetter, B. Arikan, and W. Kaminsky, Copolymerization of eth-ene with norbomene using palladium(II) a-diimine catalysts Influence of feed composition, polymerization temperature, and ligand structure on copolymer properties and microstructure, Polymer, 47 (10) 3302-3314, May 2006. 

With larger amount of propylene a random copolymer known as ethylene-propylene-monomer (EPM) copolymer is formed, which is a useful elastomer with easy processability and improved optical properties.208,449 Copolymerization of ethylene and propylene with a nonconjugated diene [EPDM or ethylene-propylene-diene-monomer copolymer] introduces unsaturation into the polymer structure, allowing the further improvement of physical properties by crosslinking (sulfur vulcanization) 443,450 Only three dienes are employed commercially in EPDM manufacture dicyclopentadiene, 1,4-hexadiene, and the most extensively used 5-ethylidene-2-norbomene. 

Another important use of BC13 is as a Friedel-Crafts catalyst in various polymerization, alkylation, and acylation reactions, and in other organic syntheses (see Friedel-Crafts reaction). Examples include conversion of cydophosphazenes to polymers (81,82) polymerization of olefins such as ethylene (75,83—88) graft polymerization of vinyl chloride and isobutylene (89) stereospecific polymerization of propylene (90) copolymerization of isobutylene and styrene (91,92), and other unsaturated aromatics with maleic anhydride (93) polymerization of norbomene (94), butadiene (95) preparation of electrically conducting epoxy resins (96), and polymers containing B and N (97) and selective demethylation of methoxy groups ortho to OH groups (98). 

The validity of the non-steady state assumption is shown in Figure 1, where the molecular weight of the copolymerization mixture increases with conversion at the beginning of copolymerization. The long lived radical is observed from the ESR spectrum in Figure 2, measured at room temperature for polymerization in toluene this agrees with the S02 radical similar to the norbomene-S02 system (16). 

The fullerene monomer (200), made by the cycloaddition of quadricyclane (199) to Cgo (equation 56), can be copolymerized with an excess of norbomene in the presence of 8 (R = Me) to yield a high-molecular-weight, soluble, film-forming copolymer (86% cis), containing 1% of C60 derivative and exhibiting electronic and electrochemical properties which are typical of the carbon cluster536. 

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