Ethylene propylene diene monomer synthetic rubbers

Ethylene—Propylene Rubber. Ethylene and propylene 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) rubber (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 rubbers such as SBR and PBD. Ethylene—propylene rubber (EPR) requires peroxide vulcanization. 

FKMs are coextruded with lower-cost copolymers such as etliylene acrylic copolymer. They can be modihed by blending and vulcanizing with other synthetic rubbers such as silicones, ethylene propylene rubber (EPR) and ethylene propylene diene monomer (EPDM) rubbers, epichlorohydrin, and nitriles. Fluoroelastomers are blended with modihed nitrile butadiene rubber (NBR) to obtain an intermediate performance-cost balance. These blends are useful for underhood applications in environments outside the engine temperature zone such as timing chain tensioner seals. Fluoroelastomers can also be blended with fluorosilicones and other high-temperature polymers to meet engine compartment environments and cost-performance balance. 

The elastomer determines most of the physical and chemical characteristics of a rubber compound. Typical elastomers are natural elastomers such as natural rubber (NR), sometimes called crepe, and synthetic elastomers such as butyl (including chlorobutyl and bromobutyl), ethylene propylene diene monomer (EPDM), and styrene butadiene rubber (SBR). A list of commonly used elastomers is shown in Table 2. 

Though natural rubber, SBR, and BR represent the largest consumption of elastomers, several additional polymers merit a brief discussion because of their economic significance—nitriles, polychloroprene, butyl, and ethylene-propylene-diene monomer (EPDM) elastomers (Datta, 2004 The Synthetic Rubber Manual, 1999). 

Ethylene-propylene rubber is a synthetic hydrocarbon-based rubber made either from ethylene-propylene diene monomer or ethylene-propylene terpolymer. These monomers are combined in such a manner as to produce an elastomer with a completely saturated backbone and pendant unsaturation for sulfur vulcanization. As a result of this configuration, vulcanizates of EPDM elastomers are extremely resistant to attack by ozone, oxygen, and weather. 

Accelerated-sulfur vulcanization is the most widely used method. For many applications, it is the only rapid crossUnking technique that can, in a practical manner, give the delayed action required for processing, shaping, and forming before the formation of the intractable vulcanized network. It is used to vulcanize natural rubber (NR), synthetic isoprene rubber (IR), styrene-butadiene rubber (SBR), nitrile rubber (NBR), butyl rubber (HR), chlorobutyl rubber (ClIR), bromobutyl rubber (BUR), and ethylene-propylene-diene-monomer rubber (EPDM). The reactive moiety for all of these elastomers can be represented by... 

Parylene is used as a coating on electronics ranging from advanced military and aerospace electronics to general-purpose industrial products, medical devices ranging from silicone tubes to advanced coronary stents, synthetic rubber products ranging from medical grade silicone rubber to ethylene propylene diene monomer rubber (EPDM). 

Use of nanoparticles as fillers in mbbers is highly relevant because end use applications of rubber compounds require filler reinforcement. Most of the literature on rubber nanocomposites is based on the use of nanoclay as the filler. It has been shown that incorporation of nanoclay in synthetic rubbers, like styrene butadiene rubber (SBR), chloroprene rubber (CR), nitrile rubber (NBR), ethylene propylene diene monomer (EPDM) mbber etc. enhances the mechanical, anti-ageing and barrier properties. 

Both natural and synthetic rubbers are used as elastomeric linings. The most commonly used synthetic elastomers are NBR (acrylonitrile-butadiene), Hypalon (chlorosulfonated polyethylene), EPDM (ethylene-propylene-diene monomer), EPT (ethylene-propylene-diene terpolymer), SBR (styrene-butadiene), and neoprene (polychloroprene). A maximum use temperature of nS F/SOX is typical. 

Ethylene-propylene rubber is a synthetic hydrocarbon based rubber made either from ethylene-propylene diene monomer (EPDM) or from ethylene-propylene terpolymer (EPT). 

The natural rubber does not generally exhibit all the desired properties for use in the rubber industry. Thus, it is possible to obtain better mechanical and physical properties at a lower cost by blending natural rubber with synthetic rubbers. Normally, natural rubber is deteriorated by ozone and thermal attacks due to its highly unsaturated backbone, and it also shows low oil and chemical resistances due to its non-polarity. However, these properties can be achieved by blending it with low unsaturated ethylene propylene diene monomer rubber, styrene butadiene rubber, carboxylate styrene butadiene rubber, nitrile butadiene rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, and acrylonitrile butadiene rubber. 

Rubber can be divided into natural rubber and synthetic rubber on the basis of its source. Natural rubber is prepared from rubber-containing plants in nature, such as a high-elasticity material produced from natural rubber trees. Synthetic rubber is a synthetic macromolecular elastic material prepared by artificial methods. The main varieties of synthetic rubber are styrene-butadiene rubber, butadiene rubber, chlo-roprene rubber, isoprene rubber, butyl rubber, and ethylene-propylene-diene monomer rubber. 

In nontire applications, there has been a faster growth in the use of synthetic rubbers such as ethylene-propylene-diene monomer (EPDM) and nitrile rubbers, as a substitute for SBR. However, nontire uses for SBR are growing with applications including conveyor belts, gaskets, floor tiles, footwear, and adhesives. 

FRP—Fiberglass-Reinforced Polyester PVC—Polyvinyl Chloride EPOM—Ethylene Propylene Diene Monomer NEOPRENE—A Chloroprene polymer, synthetic rubber... 

Polymers such as poly(vinyl chloride) (PVC), ethylene-propylene-diene monomer (EPDM), chlorosulfonated polyethylene, ketone ethylene ester (KEE), reinforced polyurethane, butyl rubbers, and polychloroprene (neoprene) have proven to be suitable for roofing membranes.In the last ten years, a new synthetic roofing material (thermoplastic polyolefins)... 

Impact-modified copolymer typically is a block copolymer with a rubbery component as one of the components of the matrix. In PP, this rubbery component typically is ethylene propylene diene monomer (EPDM), a synthetic rubber. 

Vulcanization or cross-linking chains by reacting the double bond in natural rubber with sulfur and other crosslinking agents is used to limit stress induced flow in natural rubber. Various means were tried to crosslink the synthetic elastomer ethylene propylene rubber (EPR). The technique commonly used is based on experience with natural rubber. A small amount of a diene [a monomer with two double bonds] is incorporated into the EPR chain to furnish sites for vulcanization reactions. 

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