Characteristics of ethylene propylene diene monomer rubber/organoclay nanocomposites resulting from different processing conditions and formulations

Abstract

Several parameters which affect the nanocomposite formation in a sulfur‐cured ethylene propylene diene rubber (EPDM) containing 10 phr organoclay (montmorillonite modified with octadecylamine; MMT–ODA), were investigated. The parameters varied were linked to processing (mixer type, temperature) and rubber recipe (compatibilizer, accelerator). Increasing temperature and high shear mixing (internal mixer instead of open mill) improved the mechanical performance of the rubber nanocomposites. A more pronounced effect was achieved by using polar EPDM rubbers (maleic anhydride and glycidyl methacrylate grafted version) as compatibilizer. Among the accelerators, zinc diethyldithiocarbamate proved to be most suitable. The microstructure of the rubber/organoclay systems was studied by X‐ray diffraction, transmission electron microscopy and scanning electron microscopy. Organoclay intercalation/exfoliation was accompanied by its more or less severe confinement (reaggregation, deintercalation). This was traced to a partial or full removal of the ODA intercalant from the clay galleries via the formation of a zinc complex in which amine groups of the ODA and sulfur participated. Copyright © 2004 Society of Chemical Industry

Nitrile rubber - based nanocomposites prepared by melt mixing: effect of the mixing parameters on mechanical, dynamic-mechanical and creep behavior

“…Zhang et al [24] have compounded different rubbers with clay in a two roll-mill and observed that part of the clay have been intercalated by the rubber chains and another part have been re-aggregated after curing, probably because of the expulsion of some organic cations. Similar behavior has been also observed in other rubber-clay systems [19,29,[33][34][35][36][37] . The intercalated structures of the organoclays in a rubber matrix and their spatial distribution are significantly affected by the curing parameters during the vulcanization process [31,32,36] .…”

Rubber curing chemistry governing the orientation of layered silicate

“…During the course of rubber curing different types of intermediate chemical species are formed in the rubber matrix. It is expected that vulcanization ingredients can further interact with the organoclay during the vulcanization of rubber at higher temperatures and pressure [11]. These unavoidable interactions could be reflected on the final microstructure of layered silicates.…”

Nanocomposites of poly(methyl methacrylate) (PMMA) and montmorillonite (MMT) Brazilian clay: A tribological study

“…Fillers are a way to improve a variety of properties of PBMs [20] and clays have been used for that purpose [21][22][23][24][25]. We find that clay content in the nanocomposites has an influence on the dynamic friction and wear rate values.…”