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Rubber, epoxidized natural

Epoxidized natural rubber (ENR) is an important modified form of natural rubber whose properties are close to those of special purpose synthetic rubbers. ENR is prepared by reacting natural rubber in latex form with performic acid formed in situ by the reaction of formic acid and hydrogen peroxide under controlled conditions. [45,46]. The double bonds of natural rubber react readily with peracids to yield epoxide groups. Though any level of epoxidation can be achieved, only up to 50 mole percent is used in practice. 50, 25, and 10 mole% epoxidized products are termed ENR-50, ENR-25, and ENR-10. Studies using NMR have shown that the epoxide groups are randomly distributed along the natural rubber backbone [47]. [Pg.426]

As compared to natural rubber, epoxidized grades of natural rubber show improved reinforcement with silica without any coupling agent. Radial tyre tread prepared using formulations based on natural rubber with epoxide [Pg.426]

Table 5. Physical Properties of Black-Filled Epoxidized Natural Rubber ... Table 5. Physical Properties of Black-Filled Epoxidized Natural Rubber ...
In all the compositions, the DCP-cured blends showed better properties than the corresponding unvulcanized samples. Choudhary et al. [30] further demonstrated the use of EPDM, chlorinated PE, chlorosulfo-nated PE, maleic anhydride modified polyethylene, and blends of epoxidized natural rubber-sulfonated EPDM as compatibilizers in NR-LDPE (low-density PE) blends. [Pg.640]

ATBN - amine terminated nitrile rubber X - Flory Huggins interaction parameter CPE - carboxylated polyethylene d - width at half height of the copolymer profile given by Kuhn statistical segment length DMAE - dimethyl amino ethanol r - interfacial tension reduction d - particle size reduction DSC - differential scanning calorimetry EMA - ethylene methyl acrylate copolymer ENR - epoxidized natural rubber EOR - ethylene olefin rubber EPDM - ethylene propylene diene monomer EPM - ethylene propylene monomer rubber EPR - ethylene propylene rubber EPR-g-SA - succinic anhydride grafted ethylene propylene rubber... [Pg.682]

They have studied the properties of NR-epoxidized natural rubber (ENR) blend nanocomposites also. Vulcanization kinetics of natural mbber-based nanocomposite was also smdied. The effect of different nanoclays on the properties of NR-based nanocomposite was studied. The tensile properties of different nanocomposites are shown in Figure 2.7 [33]. [Pg.35]

FIGURE 3.12 Morphology of mbber-silica hybrid composites synthesized from solution process using different solvents (a) and (b) are the scanning electron microscopic (SEM) pictures of acrylic rubber (ACM)-silica hybrid composites prepared from THF (T) and ethyl acetate (EAc) (E) and (c) and (d) are the transmission electron microscopic (TEM) pictures of epoxidized natural rubber (ENR)-siUca hybrid composites synthesized from THF and chloroform (CH). (From Bandyopadhyay, A., De Sarkar, M., and Bhowmick, A.K., J. Appl. Polym. Sci., 95, 1418, 2005 and Bandyopadhyay, A., De Sarkar, M., and Bhowmick, A.K., J. Mater. Sci., 40, 53, 2005. Courtesy of Wiley InterScience and Springer, respectively.)... [Pg.69]

FIGURE 3.16 Morphology and visual appearance of acrylic rubber (ACM)-silica and epoxidized natural rubber (ENR)-silica hybrid composites prepared from different pH ranges (a) transmission electron microscopic (TEM) picture of ACM-siUca in pH 1.0-2.0, (b) scanning electron microscopic (SEM) picture of ACM-siUca in pH 5.0-6.0, (c) SEM image of ACM-siUca in pH 9.0-10.0, (d) TEM picture of ENR-silica in pH... [Pg.74]

FIGURE 3.19 Comparative Kraus plots of acrylic rubber (ACM)-silica and epoxidized natural rubber (ENR)-silica hybrid nanocomposites at different in situ silica concentrations. (From Bandyopadhyay, A., De Sarkar, M., and Bhowmick, A.K., J. Polym. Sci., Part B Polym. Phys., 43, 2399, 2005. Courtesy of Wiley InterScience.)... [Pg.76]

When two polymers interact or react with each other, they are likely to provide a compatible, even a miscible, blend. Epoxidized natural rubber (ENR) interacts with chloro-sulfonated polyethylene (Hypalon) and polyvinyl chloride (PVC) forming partially miscible and miscible blends, respectively, due to the reaction between chlorosulfonic acid group and chlorine with epoxy group of ENR. Chiu et al. have studied the blends of chlorinated polyethylene (CR) with ENR at blend ratios of 75 25, 50 50, and 25 75, as well as pure rubbers using sulfur (Sg), 2-mercapto-benzothiazole, and 2-benzothiazole disulfide as vulcanizing agents [32]. They have studied Mooney viscosity, scorch... [Pg.316]

Mathai, A.E., Singh, R.P., and Thomas, S. Transport of Aromatic Solvents through Nitrile Rubber/Epoxidized Natural Rubber Blend Membranes, Polym. Eng. Set 43(3), 704—712, March 2003. [Pg.349]

The third and newest modified natural rubber available is epoxidized natural rubber (ENR). This modification was actually discovered as early as 1922 (50), although the elimination of ring opening and side reactions to give a purely epoxidized material took another 50 years or so to achieve (51). The resulting polymer is a new material, with properties totally different from natural rubber, as indicated in Table 5. [Pg.271]

Epoxidized natural rubber is still a strain crystallizing mbber and therefore retains the high tensile strength of natural rubber. However, as can be seen from Table 5, in other respects they have very little in common. The epoxidation renders a much higher damping mbber, a much-improved resistance to oil swelling (insofar as a 50 mol % modified natural mbber has similar oil resistance to a 34% nitrile mbber), and much-reduced air permeability. This latest form of modified natural mbber therefore widens the applications base of the natural material and enables it to seek markets hitherto the sole province of some specialty synthetic mbbers. [Pg.271]

Epoxidized natural rubber Ethylene propylene rubber see also EPDM Ethylene propylene rubber see also EPM Ethylene vinyl acetate... [Pg.463]

Ismail, H. Suzaimah, S. Hairunezam, H.M. Curing characteristics, mechanical properties and oil resistance of styrene butadiene rubber/epoxidized natural rubber blends. J. Elastomers Plast. 2002, 34 (2), 119-130. [Pg.2879]

PP/EPDM/epoxidized natural rubber (246) PP/epoxidized natural rubber (301) Butadiene/styrene-butadiene rubber (293) EPDM/PA66 EPDM/SBR (68)... [Pg.11]

Natural mbber/reclaimed rubber (252) Epoxidized natural rubber/natural rubber (253)... [Pg.12]

Fig. 14 UV-curing of various blends of EPI with HDDA (20 wt %). Photoinitiator [TAS] = 3 wt % ENR epoxidized natural rubber ECR epoxidizedcyclized rubber. Epoxy conversion acrylate conversion... Fig. 14 UV-curing of various blends of EPI with HDDA (20 wt %). Photoinitiator [TAS] = 3 wt % ENR epoxidized natural rubber ECR epoxidizedcyclized rubber. Epoxy conversion acrylate conversion...
As natural rubber is a product of nature, its properties are determined by the biochemical pathway by which the polymer is synthesized in the plant. In the case of natural rubber the polymerization process cannot be tailored like that of synthetic rubbers. The only option to modify natural rubber is after it has been harvested from the tree. The important modified forms of natural rubber include hydrogenated natural rubber, chlorinated natural rubber, hydro-halogenated natural rubber, cyclized natural rubber, depolymerised liquid natural rubber, resin modified natural rubber, poly(methyl methacrylate) grafted natural rubber, poly(styrene) grafted natural rubber, and epoxidized natural rubber [33,34]. Thermoplastic natural rubber prepared by blending natural rubber and PP is considered as a physically modified form of natural rubber. [Pg.424]

See other pages where Rubber, epoxidized natural is mentioned: [Pg.367]    [Pg.948]    [Pg.681]    [Pg.78]    [Pg.389]    [Pg.903]    [Pg.563]    [Pg.3]    [Pg.136]    [Pg.144]    [Pg.225]    [Pg.903]    [Pg.2877]    [Pg.933]    [Pg.415]    [Pg.1402]    [Pg.15]    [Pg.452]    [Pg.287]    [Pg.300]    [Pg.426]    [Pg.426]    [Pg.427]    [Pg.435]   
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