ABSTRACT
Synthesized Layered Silicates (SLS), such as octosilicate, is presented in this work as an alternative to overcome the dispersibility issue. Analogous to MMT the SLS require organic modification by ion-exchange with long-tailed cations resulting in an extension of the layer-spacing and compatibilisation with the rubber matrix facilitating the dispersion and exfoliation of the SLS-sheets. However, SLS have some important differences to MMT: the former have interlayer silanol with specifically ordered, negatively charged sites of SiO− (Takahashi and Kuroda, 2011), while the charged
1 INTRODUCTION
Polymers filled with organically Modified Montmorillonite (MMT) have attracted intensive research interest due to the potential benefits as highly active reinforcing filler or as additive to reduce liquid and gas permeability. The introduction of these property-enhancements of the pure polymer matrix by the filler is directly related to the highly anisometric structure of the layers of the smectite clays and the potentially extreme accessible filler surface in case of complete exfoliation. However, the potential benefits from the large anisometry of the clay-layers also pose the biggest challenge-the
sites in MMT arises from isomorphous substitution within the layers with no defined order. Cation-exchange should therefore yield a more regular coverage of the silicate-layers with longtailed cations and hence a better overall compatibilisation promoting intercalation and exfoliation.
