Mechanical, rheological, and swelling behavior of natural rubber/montmorillonite aerogels prepared by freeze-drying

Montmorillonite (Na+-MMT) aerogel/prevulcanized natural rubber (PNR) composites were produced by freezing–drying. The composites exhibited densities in the range of 0.36–0.51 g cm− 3, which was in good agreement with the content of polymer in the aqueous solutions. The dispersion of the Na+-MMT particles and the microstructure of the composites were investigated by X-ray diffraction and scanning electron microcopy. The influence of the Na+-MMT particles on the mechanical, rheological and swelling properties of the composites was investigated. A composite made from 7 parts per hundred of rubber (phr) of Na+-MMT showed the greatest improvement in material properties. Such Na+-MMT aerogel/polymer composites will be candidates for structural and insulation applications.