Antioxidants nitrile rubber

NBR antioxidant pLASTOTffiRS, SYNTTiETIC - NITRILE RUBBER] (Vol 8) Octylated diphenylamines [101-67-7]... 

Because nitrile rubber is an unsaturated copolymer it is sensitive to oxidative attack and addition of an antioxidant is necessary. The most common practice is to add an emulsion or dispersion of antioxidant or stabilizer to the latex before coagulation. This is sometimes done batchwise to the latex in the blend tank, and sometimes is added continuously to the latex as it is pumped toward further processing. PhenoHc, amine, and organic phosphite materials are used. Examples are di-Z fZ-butylcatechol, octylated diphenylamine, and tris(nonylphenyl) phosphite [26523-78-4]. All are meant to protect the product from oxidation during drying at elevated temperature and during storage until final use. Most mbber processors add additional antioxidant to their compounds when the NBR is mixed with fillers and curatives in order to extend the life of the final mbber part. 

Researchers at Goodyear 121 have successfully exploited route 1 above to produce antioxidant-modified SBR and NBR for example, Chemlgum HR 665, is a commercial grade of nitrile rubber containing a... 

Antiozonant additives are employed with unsaturated rubbers such as natural rubber, nitrile rubber, styrene-butadiene rubber, etc., to minimise the atmospheric ozone degradation reaction. Common antiozonant types include the parapheny-lene diamines such as N-(l,3-dimethylbutyl)-AT-phenyl-p-phenylene diamine (6PPD) and N-isopropyl-N7 phenyl-p-phenylene diamine (IPPD). Both these antioxidants can be identified and quantified using GC- or LC-based techniques. 

A general purpose antioxidant for natural rubber, SBR and nitrile rubbers. Staining, now obsolescent. 

Uses Copolymerized with methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, or 1,1-dichloroethylene to produce acrylic and modacrylic fibers and high-strength fibers ABS (acrylonitrile-butadiene-styrene) and acrylonitrile-styrene copolymers nitrile rubber cyano-ethylation of cotton synthetic soil block (acrylonitrile polymerized in wood pulp) manufacture of adhesives organic synthesis grain fumigant pesticide monomer for a semi-conductive polymer that can be used similar to inorganic oxide catalysts in dehydrogenation of tert-butyl alcohol to isobutylene and water pharmaceuticals antioxidants dyes and surfactants. 

Figure 6. Decay in elongation at break (Eg) of nitrile rubbers containing antioxidants (2%) in a cyclical hot oil (150 C)/...

Beilstein Handbook Reference) Aceto DIPP Agerite White AgeRite W AI3-14324 Antigene F Antioxidant 123 Antioxidant DNP ASM-DNT 1,4-Benzenediamine, N,N -di-2-naphthalenyl- N,N -Bis-(2-naftyl)-p-fenylendiamin 1,4-Bis(2-naphthylamino)-benzene N,N -Bis((3-naphthyl)-p-phenylenediamine N,N -Bis(2-naphthyl)-p-phenylenediamine BRN 2224419 CCRIS 6026 Oi-(3-naphthyl-p-phenyldi-amine Di-(J-naphthyl-p-phenylenediamine s-Di(P-naphthyl)-p-phenylenediamine N,N -Di-p-naphlhyl-p-phenylene-diamine N,N -Di-2-naphthalenyl-1,4-benz-enediamine N,N -Di-2-naphthyl-p-phenylenediamine Diafen NN DNPD Dnpda Dwu-p-naftylo-p-fenylodwuamina EINECS 202-249-2 Nonox CL NSC 3410 p-Phenylenediamine, N,N -(di-2-naphthyl)- N,N -p-Phenylenebis(2-naphthylamine) Santowhite CL Tisperse MB-2X. Antioxidant, An antidegradant for latex, nitrile rubber, styrene-butadiene and nitrile-butadiene rubber. Solid mp = 224-230° d n 1.22-1.28 insoluble in H2O, EtOH, soluble in organic solvents LDso (rat orl) = 4500 mg/kg. Vanderbilt R. T. Co. Inc. 

In the case of BR or SBR, the efficiency can be much greater than 1.0, especially if aU antioxidant materials are removed. A chain reaction is indicated here. One might expect that nitrile rubber would also be vulcanized with efficiencies greater than 1.0 however, though the double bonds in nitrile mbber are highly accessible, the cross-linking efficiency is somewhat less than 1.0. 

Uses antioxidant stabilizer polymerization inhibitor intermediate in organic synthesis antidegradant for latex, nitrile rubber, styrene-butadiene, and nitrile-butadiene rubber A... 

Uses antioxidant for rubber, petroleum oils, and feedstuff s stabilizer a polymerization inhibitor used to retard copper degradation as an intermediate for dyes, drugs, plastics and detergents antidegradant for nitrile-butadiene rubber, natural, styrene-butadiene, isoprene, butadiene, and chloroprene rubbers A... 

Ogawa and co-workers [136] analysed the compounds resulting from the deterioration of antioxidants in nitrile rubber sheet by ozone. 

Rubber goods, (styrene-butadiene, natural and nitrile rubbers) Ailimentary fats 2,2 methylene his- 6-tert butyl-4-methyl phenol) antioxidant Spectrophotometric [154- 156]... 

A second test which is even more discriminating is the so-called "contamination test, in which the rubber is soaked in the fluid for several hours at room temperature and is then subjected to hot air ageing at high temperature. This test simulates the environment of many engine components (e.g. seals, gaskets, hoses, etc.). The main rubbers commonly used in such applications are nitrile rubbers which are not appreciably swelled by hydrocarbon oils and ethylene-propylene (EP) and their ter-polymers (EPDM) which are resistant to the phosphate ester fluids (e.g. Skydrol) used in aircraft hydraulic systems. The following discussion is concerned with the performance of antioxidants under these veiry aggressive conditions. 

Nitrile rubber containing the antioxidant specified in Fig. 3 exhibits improved oxygen absorption resistance both before and after methanol extraction (Fig. 4). This property has been confirmed in final product application testing where the non-volatility and non-extractability of the stabilizer guarantees a long-term antioxidant effect.A range of antioxidant-bound NBR polymers has now been commercialized and a comparison of the typical physical property differences of the medium-low acrylonitrile content polymer when compared with a conventional NBR is shown in Table 5. 

As noticed above, the exact separation of rubber ingredients such as curatives, emulsifiers and antioxidants from the oil-loss curve is hardly ever possible by TG, even with the use of DTG [25]. However, HRTGA, mass detection and multivariate analysis are means which still need to be explored. The effect of high resolution was clearly noticed in a (nitrile rubber, PVC)/plasticiser sample, which shows simultaneous evolution of plasticiser and decomposition of PVC in a linear programmed heating mode, better separation in vacuum TG conditions with constant heating, and plasticiser evolution before PVC decomposition in a controlled rate heating mode [271]. 

Py-LVEIMS and PyHRMS were used in the determination of structure and composition of clinically important polyurethanes, PEUUs (Biomer, Lycra Spandex, Tecoflex and Pellethane) [746]. The antioxidants found in Biomer and Lycra Spandex were identified as well as an AO in Pellethane and an antistatic agent or residual catalyst in Biomer and Lycra Spandex. These tools are valuable for QC of implant material. PyMS is widely used in quality control of industrial products, such as foils and packaging materials [747], silicone and nitrile rubbers [748], can coatings and rubber sealing and tobacco [749]. In particular, it appears that Py-FIMS finds application not only for research in structure determination of non-volatile polymers, but also in product control. Schulten et al. [692] have described the application of Py-FIMS to paints (commercial can coatings), epoxy and polyester resins. Polyamides, acrylic and methacrylic resins, have been analysed in the same way [750-753], Py-FIMS is well suited for these investigations and allows identification of different polymer sub-units, such as monomers, dimers, backbone fragments, etc. Moreover, the technique enables differentiation of the examined compounds, which is of interest to industrial quality control. 

Vulkanox HS is an antioxidant with relatively weak staining and discoloration characteristics, it provides outstanding heat protection in natural rubber (MR), synthetic polyisoprene (IR), polybutadiene (BR), styrene butadiene rubber (SBR), nitrile rubber (NBR) and ethylene propylene rubber (EPIBl), but is less suited>le for polychloroprene (CR). Its performance is improved further in combination with Vulkanox MB-2 antioxidant, which is especially effective in thiuram cured articles with low levels or sulfur or without sulfur. Vulkanox HS antioxidant also yields good protection against rubber poisons. 

Antioxidants. All nitrile rubber producers add an antioxidant to their raw nitrile rubbers. However, where heat resistance and the maximum in durability and service is demanded, additional antioxidant may be added to the cement. Antioxidants commonly used in nitrile rubbers (e.g., amine antioxidants) may be used if staining is not a factor. Antioxidants may also contribute stability and tack. 

Ogawa and co-workers [62] carried out an analysis of the components obtained by Py-GC-MS at 350-650 °C of the components of ozone deteriorated rubber sheets containing quinoline type antioxidants such as polymerised 2,2,4-trimethyl-l,2-dihydroquinoline. There were three peaks related to the antioxidant in the pyrogram of each nitrile rubber sheet. An examination was made of the relationship between the decrease of the antioxidant and the mechanical strength of the sheet. It was found that the mechanical strength of the nitrile rubber sheet surface layer (0.1 mm) became zero when the content of this antioxidant reached 50% or less of its original level. 

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