Rubber Chloroprene-nitrile

A convenient term for any material possessing the properties of a rubber but produced from other than natural sources. A synthetic version of natural rubber has been available for many years with the same chemical formula, i.e., cis-1,4-polyisoprene, but it has not displaced the natural form. See also Butyl Rubber, Chloroprene Rubber, Ethylene-Propylene Rubber, Nitrile Rubber, Silicone Rubber and Styrene-Butadiene Rubber. 

Butadiene is a colorless, odorless, flammable gas, with a boiling point of -4.7°C and is used for the manufacture of polybutadiene, nitrile rubber, chloroprene, and various other polymers. An important synthetic elastomer is styrene-butadiene rubber (SBR) in the automobile tire industry. Specialty elastomers are polychloroprene and nitrile rubber, and an important plastic is acrylonitrile/butadiene/styrene (ABS) terpolymer. Butadiene is made into adiponitrile, which is converted into hexamethylenediamine (HMDA), one of the monomers for nylon. 

Property Natural Rubber Butyl Rubber EPDM rubber Chloroprene rubber Nitrile rubber Silicone rubber Chloro sulfon ated polyethylene rubber... 

Other systems investigated by this group are butyl rubber, - natural rubber sensitized with acrylates,chloroprene, chlorobutyl rubber and nitrile rubber.More recently, Perera has examined the relationship between chemical changes in radiation-grafted natural rubber, determined using MAS NMR, and mechanical properties measured using dynamic mechanical analysis. 

E/TFE = ethylene/tetrafluoroethylene, E/CTFE = ethylene/chlorotrifluoroethylene, EPE = oxide, E/VAL = ethylene/vinyl alcohol, FEP = tetrafluoroethylene/hexafluoropropylene, FU = furan, pA = polyamide, PCTFE = polychlorotrifluoroethyl-ene, HDPE = high-density polyethylene, PF = propylene formaldehyde, PFA = perfluoro alkoxyalkane, PP = polypropylene, PTFE = polytetrafluoroethylene, PUR = polyurethane, PVC = polyvinyl chloride, PVDF = polyvinylidene fluoride, UP = unsaturated polyester, UP-GF = fiberglass-reinforced unsaturated polyester, VE-GF = fiberglass-reinforced vinyl ester, FU-GF = fiberglass-reinforced furane, EP-GF = fiberglass-reinforced ester, CR = chloroprene rubber, CSM = chlo-rosulfonyl polyethylene, FPM = vinylidene fluoride/hexafluoropropylene copolymer, HR = isobutane-isoprene rubber, NBR = nitrile-butadiene rubber, NR = natural rubber, SBR = styrene-butadiene rubber. 

Uses Plasticizer for PVC, nitrile rubber, chloroprene rubber, extrusion and molding film, sheet and coated fabric for automotive, weather-stripping, pool liners, membranes, tarps, specialty wire and cable applies. pure grade as stationary liq. phase in chromatography... 

Natural rubber, epoxidized Nitrile rubber, carboxylated Chloroprene Single Tg I was 50 mol% epoxidized II was Krynac-211 I/II/III =1/1/1 Alex et al. (1990)... 

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. 

Fig. 3. Diffusion coefficients of nitrogen in diene rubbers and in butyl rubber as a function of T - Tg (Data from Ref 104). H Chloroprene rubber (neoprene) styrene butadiene rubber B natural rubber B nitrile butadiene rubber B butyl rubber.

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. 

Ta b I e 5.62 Upper and lower temperature limits for elastomeric materials (R C backbone with unsaturated units, M C backbone with only saturated units, 0 both C and 0 in the backbone, U C, N and 0 in the backbone, T C and S in the backbone, Q siloxane backbone NR natural rubber, IR isoprene rubber, BR butadiene rubber, CR chloroprene rubber, SBR styrene butadiene rubber, NBR nitrile rubber, HR butyl rubber, EPDM ethylene propylene ter-rubber, EAM ethylene vinyl acetate rubber, FKM fiuoro rubber, ACM acrylate rubber, CSM chlorosulfonated polyethylene, CM chlorinated polyethylene, ECO epichlorohydrin rubber (epichlorohydrin, ethylene oxide), AU polyurethane rubber (did), EU polyurethane rubber (diisocyanate), VMQ silicone rubber) specialties [229]... 

Fuh and Wang [31] conducted studies involving Py-GC-MS for the analysis of nitrile rubber/chloroprene rubber materials. The peak ratio of l-chloro-4-(l-chloroethenyl) cyclohexane and benzonitrile was used for quantitative measurement of chloroprene/ nitrile rubber composition in vulcanised samples. Good linearity and recovery were achieved. A series of vulcanised chloroprene-nitrile rubber blended rubber materials was analysed using this method. Reasonable agreement between the estimated and the actual chloroprene composition of these commercial rubber materials was obtained. 

An excsllent low tea erature plasticizer for a wide range of polynere, particularly nitrile rubber, chloroprene rubber and polyvinyl chloride. It is essentially the ester of triethylene glycol with linear acids, average carbon nuaber C9 and gives superior low teagierature performance to the adipates end the sebacates. 

Uses Crosslinking agent for resin/rubber mixts. such as chloroprene, nitrile, NR ... 

Natural rubber, epoxidized Nitrile rubber, Chloroprene Single Tg I was 50 mol% epoxidized 14... 

Rubbers. Plasticizers have been used in mbber processing and formulations for many years (8), although phthaHc and adipic esters have found Htde use since cheaper alternatives, eg, heavy petroleum oils, coal tars, and other predominandy hydrocarbon products, are available for many types of mbber. Esters, eg, DOA, DOP, and DOS, can be used with latex mbber to produce large reductions in T. It has been noted (9) that the more polar elastomers such as nitrile mbber and chloroprene are insufficiendy compatible with hydrocarbons and requite a more specialized type of plasticizer, eg, a phthalate or adipate ester. Approximately 50% of nitrile mbber used in Western Europe is plasticized at 10—15 phr (a total of 5000—6000 t/yr), and 25% of chloroprene at ca 10 phr (ca 2000 t/yr) is plasticized. Usage in other elastomers is very low although may increase due to toxicological concerns over polynuclear aromatic compounds (9). 

An estimation of ZnCFO efficiency as vulcanization active component was carried out in modelling unfilled elastomeric compositions on the basis of isoprene, butadiene-nitrile, chloroprene and butyl rubbers of sulphur, thiuram, peroxide, metaloxide and resin vulcanization systems. 

ZnCFO is the effective vulcanization active component of the sulfur, thiuram, peroxide and metaloxide vulcanization systems for isoprene, nitrile-butadiene and chloroprene rubbers at the same time it is not effective in resin vulcanization system for butyl rubber. On a degree of positive influence on the properties of elastomeric compositions vulcanization systems with ZnCFO are arranged in a line ... 

Terpolymers in which the acrylate monomer is the major component are useful as ethylene-acrylate elastomers (trade name Vamac) [Hagman and Crary, 1985]. A small amount of an alkenoic acid is present to introduce sites (C=C) for subsequent crosslinking via reaction with primary diamines (Sec. 9-2d). These elastomers have excellent oil resistance and stability over a wide temperature range (—50 to 200°C). They are superior to nitrile and chloroprene rubbers. Although not superior to silicone and fluorocarbon elastomers, they are less costly uses include automotive (hydraulic system seals, hoses) and wire and cable insulation. 

Butadiene is used primarily in the production of synthetic rubbers, including styrene-butadiene rubber (SBR), polybutadiene nibber (BR), styrene-butadiene latex (SBL), chloroprene rubber (CR) and nitrile rubber (NR). Important plastics containing butadiene as a monomeric component are shock-resistant polystyrene, a two-phase system consisting of polystyrene and polybutadiene ABS polymers consisting of acrylonitrile, butadiene and styrene and a copolymer of methyl methacrylate, butadiene and styrene (MBS), which is used as a modifier for poly(vinyl chloride). It is also used as an intermediate in the production of chloroprene, adiponitrile and other basic petrochemicals. The worldwide use pattern for butadiene in 1981 was as follows (%) SBR + SBL, 56 BR, 22 CR, 6 NR, 4 ABS, 4 hexamethylenediamine, 4 other, 4. The use pattern for butadiene in the United States in 1995 was (%) SBR, 31 BR, 24 SBL, 13 CR, 4 ABS, 5 NR, 2 adiponitrile, 12 and other, 9 (Anon., 1996b). 

Polyurethane is superior to all Natural, chloroprene, SBR, and nitrile Silicone and fluoroelastomers Natural, SBR, and silicone rubbers Natural and SBR... 

Solid-state 13C NMR has been used to identify elastomers in binary blends of chloroprene (CR) and NR, CR and CSM, NR and CSM, and SBR and acrylonitrile-butadiene rubber (NBR). The type of NBR can be determined by identifying the sequences of acrylonitrile and butadiene. The tertiary blend of NR/SBR/BR was also studied [49]. High-temperature 13C solid-state NMR identified ethylene-propylene diene terpolymer (EPDM) and fluoro and nitrile rubbers [50]. 

Elastomer Natural rubber Butyl rubber Chlorinated Butyl Rubber Nitrile rubber Silicone rubber Hypalon Chloroprene Viton EPDM EVA... 

Fillers in Rubber. Carbon black and calcium silicate are able to reinforce rubber. For example, the tensile strength of an SBR vulcanizate can be raised from 350 to 3500 Ib/in. by compounding with 50% of its weight of carbon black (54). The activity of the carbon black depends on particle size and shape, porosity, and number of active sites, which are less than 5% of the total surface. Elastomers of a polar nature, such as chloroprene or nitrile rubber, will interact more strongly with filler surfaces having dipoles, such as -OH and -CCX)H groups or chlorine atoms. 

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