Olefinic blocky copolymer/montmorillonite nanocomposites with collapsed clay layers

In the present work, the nanocomposite of olefinic blocky copolymer with collapsed organically modified montmorillonite (OBC/c-OMMT) was prepared by co-precipitation of OBC and OMMT with excess ethanol. The dispersion state of clay in the nanocomposites was identified by WAXD and further confirmed by FT-IR. It is found that ethanol can extract parts of the organic modifier and OBC can further squeeze the resultant OMMT layers, yielding collapsed OMMT. Crystallization and morphology of OBC/c-OMMT were compared with those of the nanocomposites containing intercalated organically modified montmorillonite (i-OMMT) and aggregated un-modified montmorillonite (a-MMT). The collapsed OMMT has a stronger nucleation effect on crystallization of OBC than i-OMMT and a-MMT, as revealed by the higher crystallization temperature, smaller crystallite size and larger number of crystallite. Rheology test reveals that the complex viscosity of OBC/c-OMMT at low frequencies is smaller, possibly due to the lower volume fraction of c-OMMT in OBC.