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in the polyurethane/ground tire rubber foamed composites enhanced their cross-link density estimated from the swelling measurements. It was also confirmed by an increase of glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. Addition of ground tire rubber to polyurethane foams had very positive influence on their thermal stability measured by the temperature corresponding to the 2 % mass loss during degradation of material. Modification increased initial degradation temperature even by 14 °C compared to a reference sample.

This work presents thermal studies of nanocomposites based on the flexible polyurethane (PU) matrix and filled using montmorillonite organically modified with organophosphorus flame retardant compound. Flexible PU nanocomposite foams were prepared in the reaction carried out between reactive alcoholic hydroxyl and isocyanate groups with the ratio of NCO to OH groups equal to 1.05. The amount of an organoclay ranging from 3 to 9 vol% was added to the polyol component of the resin before mixing with isocyanate. The apparent density of PU foams was ranging from 0.066 to 0.077 g cm -1 . Thermal properties of the flexible PU nanocomposite foams were investigated by thermogravimetry and dynamical mechanical analysis. Glass transition temperatures (T g ) were defined as maximum peak on tand curve. Thermal decomposition was observed at 310-320°C (calculated from the onset of TG curve). Tensile strength of the PU foams was determined using mechanical test. The microstructure of the nanoparticles and the composites was investigated by X-ray diffraction. Finally, it was confirmed that the thermal and mechanical properties of flexible PU nanocomposite depend on the amount of nanoclay.

The aim of this study was to investigate the effect of three different nanofillers on the properties of rigid polyurethane foams, which were prepared by a one-step, laboratory-scale method from a two-component system at the ratio of NCO groups to OH groups equaled to 2. The reaction mixture consisted of the proper amounts of the commercial oligoether polyol, catalysts, water, nanoclays, and polymeric diphenylmethane diisocyanate. Three types of montmorillonite were used as clay component, i.e., montmorillonite modified by methyl tallow bis-2-hydroxyethyl ammonium (Cloisite V R 30B), a synthetic layered silicate (Laponite V R RD), and an aluminium phyllosilicate absorbent, essentially impure clay consisting mostly of montmorillonite (Bentonite). Thermal properties of rigid polyurethane foams and nanocomposite foams were investigated by dynamical thermal analysis, thermogravimetry, oxygen index, and thermal conductivity measurements. It has been shown that the foams modified by selected nanofillers are characterized by high mechanical strength, as well as improved fire barrier properties.