Norbomene commercial polymer

The importance of control of MW of potential commercial polymers has led to numerous studies of the effect of various unsaturated additives on the ROMP of cycloalkenes, especially cyclopentene and norbomene (see Table 15.1). 

COC is a relatively new commercial polymer. Four commercial sources are available under the TOPAS , ApeF, Zeonor and Zeonex , and Arton product names, supplied by Topas Advanced Polymers, Mitsui Chemicals, Zeon Chemical and Japan Synthrtic Rubber. COC is a random copolymer of ethylene and norbomene. Norbomene is synthesized via Diels-Alder reaction of ethylene and cylopentadiene. Polymerization of ethylene and norbomene using metallocene catalysts produces cyclic olefin copolymer. Large bulky cyclic rings randomly distributed in a polyethylene backbone prevent crystallization of the ethylene, creating an amorphous morphology. 

The idea of using polyunsaturated monomers is rooted in the eady history of acryUc elastomers. The first monomers used were butadiene [106-99-0] (35), isoprene [78-79-5] (36), and aHyl maleate [999-21-3] (37), but they did not find commercial success because during polymerization large portions of polymer were cross-linked. Other monomers have been proposed more recentiy tetrahydrobenzyl acrylate (38), dicyclopentenyl acrylate [2542-30-2] (39), and 5-ethyhdene-2-norbomene [16219-75-3] (40). The market potential, at least for the more recent ones, is stiU to be determined. 

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. 

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. 

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. 

Copolymers of ethylene (E) or propylene (P) with acrylic acid (AA) or methacrylic acid (MA) were obtained from SP2 (USA) and used as received (EAA, PAA, PEAA, PMA). Copolymers of ethylene and vinyl alcohol (EVOH) were prepared by hydrolysis (NaOH 0,5M in methanol, reflux, 48 h), of commercial ethylene-vinyl acetate copolymers (EVA, Elf-Atochem) containing 5, 9, 14, and 18 w% of acetate. Hydroperoxides of EPDM based on 5-ethylidene-2-norbomene (0.7 mol Kg" Exxon) and polyoctenamer (Vestenamer, VEST, HUls) resulted from a reaction of polymer films with singlet oxygen. 

The possibility of controlling the interanular wedge angle of ansa-metallocene catalysts and their resulting capability to also enchain olefins, which are otherwise not readily amenable to insertion polymerization, allows the productirMi of copolymers of ethene with cyclic olefins, in particular with norbomene or its substituted derivatives. Based on first observations in this regard [73, 74], ethene/ norbomene copolymers, e.g. with alternating microstmctures [75-77] and with excellent optical and barrier properties, are now commercially produced with ansa-metallocene catalysts by Topas Advanced Polymers (TOPAS ) [78] and by Mitsui Chemical (Apel) [79]. 

There are many other commercial examples of polymer blends. Polycarbonate can be blended with an acrylonitrile-butadiene-styrene terpolymer to give a PC-ABS blend. Polypropylene impact can be improved by the addition of ethylene-propylene copolymers, which are sometimes called ethylene-propylene-rubber (EPR). Ethylene, propylene, and a diene monomer (EPDM), such as ethylidene norbomene, is also used to impart impact and flexibiUty to polypropylene. 

In 1976, polynorbomene 129 under the trade name Norsorex was the first commercial metathesis polymer product launched in market by CdF-Chimie in France. Later, in 1978, it was also marketed in the USA and Japan [57]. This polymer is produced by Ring-opening metathesis polymerization (ROMP) of 2-norbomene 128 (Scheme 9.33). This reaction was catalyzed by RuClj/HCl in butanol, which operates in air and produces a useful elastomer, used for oil spill recovery, for damping or as a sound barrier. It is presently produced in ASTROTECH Co. under the trade name Norsorex APX, to use as a miscellaneous oil spill control agent by emergency management team in USA. 

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