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A general approach to rubber-montmorillonite nanocomposites: Intercalation of stearic acid

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Details

Original languageEnglish
Pages (from-to)117-125
Number of pages9
JournalAPPLIED CLAY SCIENCE
Volume51
Issue number1-2
DOIs
Publication statusPublished - Jan 2011
Publication typeA1 Journal article-refereed

Abstract

The effect of stearic acid on the properties of different rubbers/montmorillonite composites was studied. We used alkyl quaternary ammonium modified montmorillonite (organo-montmorillonite), which was additionally modified with stearic acid. Premixed with the montmorillonite, the stearic acid expanded the clay mineral layers, thus permitting the rubber molecules to be more easily intercalated into the montmorillonite. We used several kinds of rubbers with different polarities and molecular structures. Both the X-ray diffraction and infrared spectroscopy studies indicated that the stearic acid propped up interlayer space allowing the intercalation of the rubber chains. Measurement of the physical and dynamic mechanical properties, along with studies of the composite morphology by transmission electron microscopy, very clearly showed that mixing the montmorillonite clay with stearic acid yielded various rubber nanocomposites with a high amount of intercalated and exfoliated montmorillonite particles. Either complete intercalation or increased nanostructure formation yielded as compared to the standard rubber-clay mineral composites prepared with a normal dose (2 parts per hundred of rubber) of stearic acid, can be achieved by adding a large amount of stearic acid (10 parts per hundred of rubber in our case) to non-polar rubbers (e.g. natural rubber (NR), ethylene propylene rubber (EPDM), etc.) that are not known to form totally exfoliated structures by simple melt mixing of montmorillonite and rubber.

ASJC Scopus subject areas

Keywords

  • Clay filled elastomers Rubber/montmorillonite composites, Stearic acid