Ethylene-propylene-diene-monomer EPDM

At this point in the process, thermoplastic and chlorosulfonated polyethylene (CSPE) membranes are complete and are ready for packaging. In the case of ethylene—propylene—diene monomer (EPDM), the curing step occurs before the membrane is ready for packaging. The curing process is accomphshed by placing the membrane in a large vulcanizer where the material is heated under pressure to complete the cure. 

Ethylene—Propylene Rubber. Ethylene and propjiene 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) mbber (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 mbbers such as SBR and PBD. Ethylene—propylene mbber (EPR) requires peroxide vulcanization. 

This is a nonpolar rubber with very little unsamration. Nanoclays as well as nanotubes have been used to prepare nanocomposites of ethylene-propylene-diene monomer (EPDM) rubber. The work mostly covers the preparation and characterization of these nanocomposites. Different processing conditions, morphology, and mechanical properties have been smdied [61-64]. Acharya et al. [61] have prepared and characterized the EPDM-based organo-nanoclay composites by X-ray diffracto-gram (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy... 

FIGURE 11.7 Inter-mbber bonding scheme for blending ethylene-propylene-diene monomer (EPDM) with nitrile mbber with a cross-linking agent. (From Naskar, M., Debnath, S.C., and Basu, D.K., Rubber Chem. TechnoL, 75, 309, 2002.)... 

In one of the first reports on fiber reinforcement of rubber, natural rubber (NR) was used by Collier [9] as the rubber matrix, which was reinforced using short cotton fibers. Some of the most commonly used rubber matrices for fiber reinforcement are NR, ethylene-propylene-diene monomer (EPDM) rubber, styrene-butadiene rubber (SBR), polychloroprene rubber, and nitrile rubber [10-13]. These rubbers were reinforced using short and long fibers including jute, silk, and rayon [14—16]. 

Mechanical Properties and Cure Rate Index of the Mixes—Role of Dry Bonding System on the Reinforcement of Ethylene-Propylene-Diene Monomer (EPDM) Rubber with Melamine Fiber ... 

FIGURE 12.7 Monsanto rheometric curves of ethylene-propylene-diene monomer (EPDM) rubber-melamine fiber composites [64]. A, gum compound B, compound containing 30 phr melamine fiber but no dry bonding system and C, compound containing both dry bonding system and 30 phr melamine fiber. (From Rajeev, R.S., Bhowmick, A.K., De, S.K., Kao, G.J.P., and Bandyopadhyay, S., Polym. Compos., 23, 574, 2002. With permission.)... 

FIGURE 12.10 Tapping mode atomic force microscopy (AFM) images of the section analyzes of ethylene-propylene-diene monomer (EPDM) rubber-melamine fiber composites. A, composite containing no dry bonding system B, composite containing resorcinol, hexamine, and silica in the concentrations 5, 3, and 15 phr, respectively. 

The accelerated sulfur vulcanization of general-purpose diene rubbers (e.g., NR, styrene-butadiene rubber [SBR], and butadiene rubber [BR]) by sulfur in the presence of organic accelerators and other rubbers, which are vulcanized by closely related technology (e.g., ethylene-propylene-diene monomer [EPDM] mbber, butyl rubber [HR], halobutyl mbber [XIIR], nitrile rubber [NBR]) comprises more than 90% of all vulcanizations. 

Cure Systems in Ethylene-Propylene Diene Monomer (EPDM)... 

The model describes the characteristic stress softening via the prestrain-dependent amplification factor X in Equation 22.22. It also considers the hysteresis behavior of reinforced mbbers, since the sum in Equation 22.23 has taken over the stretching directions with ds/dt > 0, only, implying that up and down cycles are described differently. An example showing a fit of various hysteresis cycles of silica-filled ethylene-propylene-diene monomer (EPDM) mbber in the medium-strain regime up to 50% is depicted in Figure 22.12. It must be noted that the topological constraint modulus Gg has... 

FIGURE 22.12 Uniaxial stress-strain cycles of ethylene-propylene-diene monomer (EPDM) samples with 60 phr silica at different prestrains = 10%, 20%, 30%, 40%, and 50% (symbols) and fittings (lines) with the stress-softening model Equations 22.19-22.24. The fitting parameters are indicated. The assumed cluster-size distribution is also shown, which differs from the one in Equation 22.24. (From Kliippel, M. and Heinrich, G., Kautschuk, Gummi, Kunststojfe, 58, 217, 2005. With permission.)... 

FIGURE 23.16 Thickness (volume) changes from exposing ethylene propylene diene monomer (EPDM) to 8300 psi inert gas pressures. 

FIGURE 30.11 Sampling along a compounding line for a filled ethylene-propylene-diene monomer (EPDM) compound curatives addition on open mill. 

FIGURE 30.12 Ethylene-propylene-diene monomer (EPDM) compounding complex modulus strain dependence samples TR, EM, and AG. 

Ethylene-Propylene-Diene Monomer (EPDM) Compounding RPA-FT Results at 100°C Complex Modulus Dependence on Strain Eit Parameters of Equation 30.3... 

FIGURE 30.17 Ethylene-propylene-diene monomer (EPDM) compounding corrected total torque harmonic content (TTHC) versus strain, at 1.0 Hz slope at 200%, as calculated with Hrst derivative of Equation 30.4 and fit parameters in Table 30.2. 

FIGURE 30.18 Ethylene-propylene-diene monomer (EPDM) compounding quarter cycle integration ratio versus strain, at 0.5 and 1.0 Hz samples at position TR (at dump), EM (after curatives addition), and AG (after cooling). 

Radiation Treatment NVP, 2-hydroxyethylmethacrylate (HEMA), and acrylamide (AAm) have been grafted to the surface of ethylene-propylene-diene monomer (EPDM) rubber vulcanizates using the radiation method (from a Co 7 source) to alter surface properties such as wettability and therefore biocompatibility [197]. Poncin-Epaillard et al. [198] have reported the modification of isotactic PP surface by EB and grafting of AA onto the activated polymer. Radiation-induced grafting of acrylamide onto PE is very important... 

FIGURE 31.6 Change of the surface energy parameters of control and modihed ethylene-propylene-diene monomers (EPDMs) with irradiation dose. (From Sen Majumder, P. and Bhowmick, A.K., Radial. Phys. Chem., 53, 63, 1998. With permission.)... 

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