Norsorex

Commercial manufacture of this polymer was first announced by CdF Chimie in 1975 following about 10 years of study on the Diels-Alder reactions of alkenes with cyclopentadiene. In 1976 a plant with a capacity of 5000 tonnes per annum was put on stream and product marketed as Norsorex. Manufacturing under licence is now being extended to American Cyanamid whilst CdF Chimie has also signed a marketing agreement with Nippon Zeon. 

Nornicotine, 2 83. See also Nicotine ( j-AT-Norprotosinomenine, 2 90 Norrish mechanisms, 23 376 Norsk Hydro, magnesium manufacturing by, 15 332-334 Norsorex, 22 363-364 North America... 

We also mentioned Vestenamer 8012, a predominantly trans polymer of cyclooctene made with a WC16 based catalyst (Degussa-Hiils), used in blends and poly-norbomene made by a catalyst generated from RuC13 in t-BuOH in the presence of air (Norsorex by Atofina, a polymer with a very high molecular weight). 

Further important industrial applications of olefin metathesis include the synthesis of 3,3-dimethyl-l-butene ( neohexene , intermediate for the production of musk perfume) from ethene and 2,4,4-trimethyl-2-pentene, the manufacture of a,co-dienes from ethene and cycloalkenes (reversed RCM), and the ROMP of cyclooctene and norbomene to Vestenamer and Norsorex , respectively. 

The best known polymerization of norbomene is the ring opening metathesis polymerization. The reaction is technically applied in the Norsorex process (7). 

Industrially, ROMP is used for the production of cheap highly unsaturated polymers e.g., Norsorex, Vestenamer. For example, poly-(norbomene) is produced in quantities of around 5 kta-1, under the tradename of Norsorex (18). Examples for commercially available grades and tradenames are shown in Table 1.9. Tradenames appearing in the references are shown in Table 1.10. 

In the Norsorex process, norbomadiene is polymerized by a ROMP type process. Polymers synthesized by ROMP have poor thermal stability and oxidative stability due to unsaturation of the main chain. They are used as thermoplastic resins or thermosetting resins. 

Metathesis of alkenes is essentially a class of reactions where an interchange of C atoms between pairs of double bonds takes place. A few representative examples are shown by the reactions listed in Fig. 7.10. The industrial use of metathesis reactions so far has been limited mainly to exchange metathesis (Fig. 7.10, top, backward reaction) as in the SHOP process, and ring-open metathesis polymerization (ROMP). As already mentioned (Section 7.5), Vas-tenamer is a polymer made by Hulls by ROMP from cyclooctene. Similarly, the polymer from norborene by ROMP is manufactured by CdF Chemie and is sold by the trade name of Norsorex . 

When cyclic alkenes are utilized as starting materials the metathesis reaction will lead to long chain polymers and/or cyclic oligomers [103, 104, 107, 108]. If a strained cyclic alkene is employed the reaction is effectively irreversible. Industrially cyclooctene (polymer Vestenamer), 2-norbornene (polymer Norsorex), and dicyclopentadiene (polymer Telene, Metton, Pentam) are used as monomers. Upon polymerization cyclooctene and 2-norbornene yield straight chain polymers while dicyclopentadiene also allows cross-linking (Scheme 5.56). 

Norsorex A process for making a thermosetting polymer from norbornene by ring-opening metathesis (ROMP). The product contains double bonds and can be crosslinked it can be made... 

Norbornene polymerization CdF Chimie Elf Atochem operated since 1976 Nippon Zeon 2 steps operated since 1991 norbornene norbornene polynorbornene (Norsorex ) hydrogenated norbornene (Zeonex ) RuCls/HCl/BuOH 25-100°C... 

The first commercial metathesis polymer was polynorbomene, which was put on the market in 1976 by CdF-Chimie under the trade name Norsorex. The polymer is obtained by ROMP of norbomene (bicyclo[2.2.1]heptene-2) (eq. (19)) and gives a 90 % trans polymer with a very high molecular weight (> 3 X 10 g/mol) and a glass transition temperature (Tg) of 37 °C. 

The process uses a RUCI3 catalyst in butanol, operates in air and produces a useful elastomer, to be used, for instance, for oil spill recovery, as a sound barrier, or for damping. Norsorex is produced by Elf Atochem in Carling (France) in a plant with a capacity of 5000 t/a [74]. 

As well as certain monomer syntheses, defined polymers can be made through homogeneous catalysis, e. g., olefin metathesis (CdF Norsorex , Hills Vestenamer , Hercules DCP ), special ring-opening metathesis (cf. Section 2.3.3), CO/C2H4 copolymerization (cf. Section 2.3.4), and other reactions (cf. Section 3.3.10.1). 

Norsorex . [AtocbonN. AnL Atochem Dentschland GmbH] Pcdynorbomene or blends synthetic elastomer used for danqfoig... 

Norsorex . [AtochemN. Am. Atochem Deutschland GmbH] Polynorbomene or blends synthetic elasunner used for damping compds. 

The ring opening metathesis polymerization (ROMP) of norbomene and other cyclic alkenes has been studied in liquid and supercritical CO2 (Scheme 4.7-19). Polynorbomenamer (Norsorex ) has very poor solubility in CO2 and the reactions proceed as precipitation polymerizations. The mthenium salt [Ru(H20)6](Tos)2 is also virtually insoluble in pure CO2 and the results with this catalyst proved difficult to reproduce because of variations in catalyst purity and reaction mixture agitation [98]. The catalytic performance could be greatly improved by working in C02/MeOH mixtures. The microstmcture of the polymer was found to be almost identical for samples prepared in neat norbomene or in CO2 and greatly differed from that obtained in MeOH or CO2/ MeOH mixtures [99]. 

Famous examples are the well-estabhshed Norsorex process (using RuXj catalysts), the Shell higher-olefins process (SHOP), and the cyclooctene ROMP to form Vestenamer rubber products [3, 5, 6]. 

Metathesis of mono- and diolefins can be performed with both homogeneous and heterogeneous catalysis. The most important processes involving metathesis steps, the SHOP process and the Phillips triolefin process, are based on heterogeneous catalysts. Homogeneous catalysts are used in the ring opening metathesis of norbor-nene (Norsorex, CDF-Chemie) and cyclooctene (Vestenamer, Hills) [7]. 

Such polymers can have both ds and trans strucmres, and a polynorbomene with a high trans content (Tg = 308 K, > 440 K), prepared using M0CI5 or RuClj catalysts, is sold as the product Norsorex. In addition, the chain contains the chiral centers (shown as —and other stereoregular strucmres are now possible. If the chirality of the centers on dther side of the double bond is the same, then a racemic diad is formed, whereas if they have opposite chiralities, a meso diad results. The structures with meso diads are called isotactic placements and those with racemic diads are called syndiotactic placements. 

ALTERNATIVE NAME, TRADE NAMES Poly(l,3-cyclopentylenevinylene), Norsorex , Telene (copolymer)... 

Norsorex Atochem North America, Inc., Philadelphia, Pennsylvania, USA... 

The product, poly[l,3-cyclopentylenevinylene], is a commercial synthetic specially rubber, with a trade name of Norsorex. Reports in the literature show that there may be more than one mechanism of termination. One of them may be a formation of cyclopropane rings. This is a typical reaction... 

Apart from the synthesis of such simple compounds, far more complex entities in the form of high molecular weight polymers reflect the bulk of current metathesis applications. A representative example along these lines is the synthesis of the ring-opened metathesis polymer 22 of norbomene (20) which proceeds as shown in Scheme 7b. Over 45,000 tons of this polymer are produced annually by this, so called, Norsorex process." Among different potential precursors for ROMP, norbomene is particularly easy to convert into polymers because the metathesis relieves the strain of the ring system. Moreover, living norbomene polymer (with the carbene still in place as in 21) can become a scaffold... 

Scheme 7. Industrial olefin metathesis applications the Phillips triolefin process for the production of butene and ethene (a) and the Norsorex process for the ring-opening metathesis polymerization (ROMP) of norbornene (b).

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