EPDM-clay

Usuki, A., Tukigase, A. and Kato, M. 2002. Preparation and properties of EPDM- clay hybrids. Polymer 43 2185-2189. 

Figure 8.39 shows that increasing the filler concentration decreases abrasion loss. Because of chemical interaction between the hydroxyl groups on clay and the ionic crosslinker in EPDM, clay reduces the abrasion loss more effectively than carbon black. Carbon black forms a weak interaction with the backbone... 

Synthesizing an Ethjdene Propjdene Diene Rubber (EPDM)-Clay... 

Recently, Ahmadi et al. [320] prepared EPDM/clay nanocomposites with organoclay that was intercalated with MA-grafted EPDM (MA-g-EPDM) and EPDM-clay composites with pristine clay via indirect melt intercalation method. Authors characterized the dispersion of the silicate layers in the EPDM matrix by XRD and TEM analysis methods. They showed that the particles of organoclay were completely exfoliated in EPDM matrix, and the mechanical, thermal, and chemical properties of nanocomposites were significantly improved compared with conventional composites. 

Silane concentration (phr) 300% Modulus (MPa) (sulfur cured EPDM, talc filled) 300% Modulus (MPa) (peroxide-cured EPDM, clay filled)... 

Ahmadi, S.J., Huang, Y.D., Ren, N.Q., Mohaddespour, A., Ahmadi-Brooghani, S.Y. The comparison of EPDM/clay nanocomposites and conventional composites in exposure of gamma irradiation. Compos. Sci. Technol. 69, 997-1003 (2009)... 

Role of stearic acid in preparing EPDM/clay nanocomposites by melt compounding. Polymer Journal, 39, 48-54. 

Lonkar, S.P., Kumar, A.P., Singh, R.P. Photo-stabilization of EPDM-clay naneKomposites effect of antioxidant on the preparation and durability. Polym. Adv. Technol. 18, 891-900... 

Usuki A., Tukigase A. and Kato M. (2002), Preparation and Properties of EPDM-clay Hybrids. Pofymer, 43,2185-9. 

Ethylene propylene diene rubber is a well-known general-purpose rubber with a significant commercial importance. It has been one of the main mbbers to be investigated with organo-treated layered silicates to study the effects of nanoreinforcement on properties.EPDM nanocomposites with clays have been prepared by simple static mixing in confined chamber such as Haake, solution blending, and on a laboratory two roll mill. However, most EPDM/clay nanocomposites have been produced by conventional, internal melt blending process. " ... 

Occasionally polymers are used to increase the viscosity of oil-base and synthetic-base muds. The polymers for this use are typically sulfonated polystyrenes or ethylene—propylene terpolymers (EPDM) (54,55). Such polymers are usually used in conjunction with an organopbilic clay. 

Microstructure-property correlations in dynamically vulcanized thermoplastic elastomers based on polypropylene (PP)/EPDM have shown that clay was nearly exfoliated and randomly distributed into the continuous polypropylene phase [23]. SEM photomicrographs revealed that the size of rubber particles increased with clay incorporation. Also, the clay layers act as nucleating agents, resulting in higher crystallization temperature and reduced degree of crystallinity. 

The migration of clay from EPDM to CR phase can also be explained as a wetting/dewetting process between polymers and filler. Hereby, the driving force of filler particle migration is the difference of the interfacial tensions between the rubbers and clay ... 

It is a common phenomenon that the intercalated-exfoliated clay coexists in the bulk and in the interface of a blend. Previous studies of polymer blend-clay systems usually show that the clay resides either at the interface [81] or in the bulk [82]. The simultaneous existence of clay layers in the interface and bulk allows two functions to be attributed to the nanoclay particles one as a compatibilizer because the clays are being accumulated at the interface, and the other as a nanofiller that can reinforce the rubber polymer and subsequently improve the mechanical properties of the compound. The firm existence of the exfoliated clay layers and an interconnected chain-like structure at the interface of CR and EPDM (as evident from Fig. 42a, b) surely affects the interfacial energy between CR and EPDM, and these arrangements seem to enhance the compatibility between the two rubbers. 

Dynamic mechanical analysis (DMA) has been carried out to understand the dynamic response of the blend after the addition of clay. The dependency of the storage modulus obtained from oscillatory tension deformation as a function of temperature is given in Fig. 44. All samples show a steep decrease of E over the temperature range T = 50 to 20°C followed by a rubbery plateau (Fig. 44a). The most exciting information, observed in this figure, is the increase of modulus values at room temperature by the addition of clay. The storage modulus increases from 2 MPa to 54 MPa with the addition of only 10 phr clay in the 25 EPDM/75 CR... 

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