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Abstract: The flammability, microhardness and transparency of nanocomposites based on poly(ethylene-co-acrylic acid) copolymers having different concentration of acrylic acid and different molar mass, their Zn ionomer and ethylene-glycidylmethacrylate copolymer as matrixes and on organically modified montmorillonite as a nanofiller have been investigated. The presence and the increase in the content of the clay lead to the increase in the limiting oxygen index and to significant reduction of the burning rate of all materials. The results from the Vickers microhardness measurements have shown that the addition of the clay to matrixes of polar functionalized polyethylenes leads to a significant increase in the microhardness of the materials, while the creep constant does not decrease significantly. The UV spectra show that the light transmittance of the materials does not change significantly in the presence of the clay, i.e., the nanocomposite films preserve the polymer transparency. The results have been interpreted by the intercalated structures of the nanocomposites investigated. [Copyright &y& Elsevier]

Abstract: The non-isothermal and isothermal crystallization of nanocomposites based on poly(ethylene-co-acrylic acid) copolymers having different concentration of acrylic acid and different molar mass, their Zn ionomer and ethylene–glycidylmethacrylate copolymer as matrices and organically modified montmorillonite as a nanofiller have been investigated. The influence of the presence and the concentration of clay on the kinetic parameters of non-isothermal and isothermal crystallization of the matrix polymer has been evaluated. The melting properties of the isothermal crystallized samples have been also studied. The addition of 5 or 10wt% clay to the matrices of the polar polymers leads to a change in the mechanism of non-isothermal and isothermal crystallization. The growth of the polyethylene spherulites changes from three- to two-dimensional when the lamellar silicate is added. Moreover, the isothermal overall crystallization rate increases in the presence of clay due to the increased nucleation rate and unchanged or decreased crystal growth rate. The results have been interpreted by the influence of the intercalated structure of nanocomposites on the crystallization behavior of the polymers under non-isothermal and isothermal conditions. [Copyright &y& Elsevier]