Norsorex process

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

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. 

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]. 

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).

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 . 

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... 

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]. 

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]. 

Metathesis can be catalyzed homogeneously and heterogeneously. The biggest applications of metathesis such as the SHOP process [4] and Phillips Triolefin process use heterogeneous catalysts. Norbornene (Norsorex by CdF Chimie), cyclooctene (Vestenamer by Hiils AG), and dicyclopenta-diene (Hercules) practice homogeneous catalysis. 

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