Mechanical and physical properties of epoxy resin based nanocomposites reinforced with polyamine functionalized carbon nanotubes

This article concerns the effect of polyamine functionalized carbon nanotubes (CNT, 0.4 wt%) used as filler in epoxy based nanocomposites on their mechanical and physical features. The functional chains present on CNT, containing one, three, or five amino groups, were bound in similar molar amount on the CNT external walls, as verified by characterization tests. Mechanical and physical properties of the nanocomposites were investigated by means of flexural, wet ability, calorimetric, morphologic, and electrical measurements. Experimental results highlighted that the presence of the amino groups attached on the CNT improves both their dispersion and chemical interaction with the matrix. Both these factors enhance the mechanical strength, deformability and wet ability of the nanocomposites compared to the neat resin which retains its thermal stability. The highest enhancement in maximum flexural strength and elongation at break (of +31% and of +110%, respectively) was observed in the nanocomposite containing the penta - amino chain while the glass transition temperature value increased of 27%.