Preparation and properties of elastomeric polyurethane/organically modified montmorillonite nanocomposites

Elastomeric polyurethane (PU) was mixed with 1, 3, 5, 7, and 10 wt% of Cloisite 30B to obtain PU-based nanocomposites. The thermal stabilities of the obtained products were characterized by thermal analysis using a thermogravimetric analyzer (TGA), which showed that the addition of 5 wt% of organoclay to the PU increased its stability, whereas thermal stabilization was less efficient at 10 wt%. The electrical conductivities of these composites were studied as a function of temperature, and it was found that the conductivity of PU was enhanced upon using 5 wt% of organoclay. The tensile strength, elongation (%), and Young’s modulus were considerably enhanced upon increasing the organoclay content to 5 wt%, but were then decreased to some extent upon further increasing the nanoparticle loading to 10 wt%. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study these nanocomposite structures, and it was found that the PU molecular chains were intercalated into the galleries of the silicate layers in all of the nanocomposites, and that this reached a maximum when 5 wt% of Cloisite 30B was used.