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The paper deals with the rheological properties of epoxy resin additivated with organically modified montmorillonites, carbon nanotubes and nanocarbon. The paper also presents the influence of nanoadditives over composites mechanical properties. The epoxy polymer is diglycidyl ether of bisphenol A (DGEBA) and the curing agent is an aliphatic tetraamine. Organically modified montmorillonites Cloisite 30B and Cloisite 93A, MWCNTs and laser synthesized nanocarbon were used to synthesize nanocomposites by dispersing each in an epoxy resin. The dispersion was achieved through mechanical and sonic methods. The epoxy resin additivated with nanosized fillers was rheologically tested to study the dispersion influence. The sonic dispersion of nanoadditives is observed to drastically influence the rheological behavior of the suspensions. Newtonian fluid behavior disappears as the additive loading increases. The work mentions the influence of nanoadditives on the manufacturing process of epoxy /glass fibre and epoxy/ carbon fibre laminated composites.

Nanocomposites from polyethylene and TiO2 with different shape and size were prepared by direct mixing and masterbatch dilution, respectively. The mechanical properties of nanocomposites were determined and discussed in relation to the nanofiller dispersion. Moreover, the morphological aspects of polyethylene with and without nanofiller were revealed by means of SEM and WAXD. A better dispersion of the nanoparticles and increased mechanical properties were observed in the case of the masterbatch method. No important differences in mechanical and morphological characteristics of anatase and rutile containing polyethylene composites were observed, except a higher increase of the elastic modulus in case of anatase-containing composites.

Nanocomposites of polypropylene with organically modified clay were obtained on a corotating extruder. The modification of clay was done by swelling with a polyetherdiamine which undergoes cross-linking reaction with maleated polypropylene. The effect of clay concentration and of thermal treatment was studied from a morphological and mechanical point of view. The structure was analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and dynamic-mechanical thermal analyses (DMTA). Nanocomposites with 1 and 2 wt- % silicate concentration presented improvement in mechanical properties. The improvements observed were: 20% increase in tensile strength, 21% increase in Young modulus, 34% reduction in creep strain and 30% decrease in tensile strain after cyclic loading, meaning improved fatigue.

In order to reuse photodegraded low density polyethylene from green houses and solars, it has been physically modified with EPDR, bitumen atactic polypropylene. Thermodynamically compatible blends, selected by DSC and dielectric spectroscopy studies, were moulded into hydroinsulating sheets, which exhibit useful properties. The influence of the degree of miscibility of the components at the molecular level on the rheological properties of melts of certain blends based on S-LD-PE is presented.

The intrinsic academic interest as well as the increasing application of polymeric composites has largely motivated the significant development of both theoretical methods and intensive experimental studies aiming at describing their mechanical behaviour in terms of the properties of individual components, volume fraction, morphology and some characteristic parameters1–3.

The utility of model rheological equations of state is now a well established question in case of polymeric materials. Using the viscoelastic operators method, we indicate the possibility to derive such equations on the basis of mechanical models to be used for polymeric composite materials.