Highly Impermeable Nanaocomposites of Brominated Butyl Rubber with Modified Montmorillonite Clay

Incorporation of nanoclays in vulcanized rubber can enhance the barrier and mechanical properties, with the aid of intercalation, exfoliation or both.  Achieving a high degree of dispersion such as, intercalation and exfoliation is critical for obtaining optimal properties.  In this work a stepwise approach was developed to disperse the natural montmorillonite clay modified with a quaternary ammonium salt (MMT) in brominated butyl rubber (BIIR). The solvent intercalation method followed by mechanical shear was used to effectively intercalate/exfoliate the MMT bundles.  Special consideration was given to effectively remove the solvent from the solvent intercalated master batch.  The nanocomposites fabricated using this technique showed high a degree of intercalation and exfoliation along with improved barrier, dynamic mechanical, and mechanical properties.  This improvement in properties offers an opportunity for this material to be utilized in high end applications requiring improved mechanical, as well as barrier properties; an example is a thinner tire inner liner with reduced hysteresis, lower running temperatures, and reduced fuel consumption.