Polynorbornene elastomers

Butadiene/acrylonitrile copolymer elastomer, golf ball thread Polyisoprene elastomer, grommets Butadiene/acrylonitrile copolymer elastomer, hardness/damping compounds Polynorbornene elastomer, hoses Acrylonitrile copolymer elastomer, hydraulic equip. 

There is, however, one further speciality rubber which perhaps should be singled out at this stage. In 1975 the French company CdF Chemie announced the availability of polynorbornene elastomers under the trade name of Norsorex. These materials were quite different from any other rubbers prepared hitherto in that the basic polymer is not itself a rubber. It is a thermoplastic powdery product with a glass transition temperature (Tg) of about +35°C. However, it has a very high compatibility with a large number of aromatic and naphthenic oils and the blends of the polymer with these oils can give rubbers with a very wide range of softness and which may also remain rubbery down to temperatures as low as — 60°C. 

The mechanical properties of X depend partly on the length of the oli-goethyleneoxy groups. The polymers are solid for x=l, highly viscous gums for x=3 and elastomers for x=7.2. The maximum conductivity of these complexes at 30 °C are reported in Table 16. Gel electrolytes have also been obtained by adding propylene carbonate (PC) (10-50 wt%) to these polynorbornene de-... 

Although, in this case, extractive disanation provides a solution in itself, it may be interesting to improve its effectiveness by avoiding complications of this type, especially since cyciopeu tadiene. and. to a lesser degree, piperylene, have many specific applications. The former is used for elastomers (EPDM, polynorbornene. transpolypentenamer etc.). 

Acrylic elastomer Acrylonitrile-butadiene rubber, hydrogenated Polyethylene, ultrahigh m.w. high-density Polynorbornene Polyurethane elastomer, thermoplastic Styrenated diphenylamine , Styrene-ethylene/butylene-styrene block copolymer seals, chemical-resistant Chlorotrifluoroethylene polymer seals, dynamic aerospace Polyfluoroalkoxyphosphazene seals, dynamic industrial Polyfluoroalkoxyphosphazene seals, dynamic military Polyfluoroalkoxyphosphazene seals, high performance Tetrafluoroethylene/perfluoromethylvinyl ether copolymer seals, oil... 

Polynorbornene Reclaims and regrinds Reprocessed synthetic Styrene-isoprene rubbers Thermoplastic elastomers Transoctenamer... 

Elastomers can be divided into two general categories, natural rubber and synthetic rubbers. Synthetic elastomers in turn are either termed general purpose rubbers (GPR) or special purpose rubbers. Natural rubber is generally obtained from southeast Asia or Africa. Synthetic rubbers are produced from monomers obtained from the cracking and refining of petroleum. The most common monomers are styrene, butadiene, isoprene, isobutylene, ethylene, propylene, and acrylonitrile. There are monomers for specialty elastomers which include acrylics, chlorosulfonated polyethylene, chlorinated polyethylene, epichlorohy-drin, ethylene-acrylic, ethylene-octene rubber, ethylene-propylene rubber, flu-oroelastomers, polynorbornene, polysulfides, sihcone rubber, thermoplastic elastomers, urethanes, and ethylene-vinyl acetate. 

Polynorbornene, the first metathesis polymer produced in industrial scale, was marketed in 1976 by CdF Chimie under the trade name Norsorex . The monomer is produced by Diels Alder reaction of cyclopentadiene and ethylene and polymerized in n-butanol using an RuCls/HCl catalyst. Norsorex is a very high molecular weight (Mn > 2 x 10 g/mol), thermoplast (rg = 35°C) with approximately 90% trans-dovhXe bonds. The polymer is compatible with high loads of extending oils and plasticizers (up to 700%) and easily vulcanizable. By addition of suitable amounts of plasticizers the polymer is converted into an elastomer (Tg = —60 °C). 

One of the most interesting of the newer elastomers is the aromatic equivalent of a polyalkenamer, polynorbornene, which is used in its plasticized form. Its introduction followed about 10 years of study of the Diels-Alder reactions of olefins with cyclopentadiene undertaken by CdF Chimie in France. In 1976 this company put on stream a plant with a capacity of 5000 tonnes per annum to produce the polymer which they market as Norsorex. 

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