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Summary: This paper shows the characterization carried out in polypropylene nanocomposites made up with different proportions of modified nanoclays (1% 2.5% and 5%). Modified nanoclay (montmorillonite) has been added to improve the mechanical properties of the original matrix and increase its heat resistance. The objective of this work is to characterize multiscale nanocomposites, from nano-scale to macroestrucutural scale using thermography, nanoindentaton and mechanical testing. [ABSTRACT FROM AUTHOR]

We present a simple strategy for the fabrication of poly(propylene) (PP) superhydrophobic surfaces, i.e., surfaces that show water contact angle (WCA) ≥ 150° after a simple dipping process. Injection-moulded PP samples were coated with titanium dioxide nanoparticles previously functionalised with trimethoxy propyl silane. Water, ethanol or xylene were used as solvents in the nanoparticles' suspensions. The prepared superhydrophobic surfaces were characterised by WCA, FTIR-ATR, SEM and profilometry measurements. PP coated samples showed very low wettability, with WCAs higher than 150° when xylene was used as a solvent. The combination of increasing the surface roughness via dipping coating process plus the low surface tension of the coating produced the final superhydrophobic PP substrates. [ABSTRACT FROM AUTHOR]

Poly(propylene) homopolymer/fly ash (50% wt) composites have been prepared from two samples of fly ash that differ in terms of the geographic source of coal feedstock, which left one of the samples with a higher group I and II metal content. A screening study indicated that Lubrizol Solplus® C800 (an unsaturated carboxylic acid dimer coupling agent), initiated with dicumyl peroxide, conferred the best strength-toughness balance to the composites. In some cases, however this was related to detachment of the interfacial region due to possible extraction of PP-C800 adduct-group I and II ion reaction products. Interfacial adhesion was arguably too high in the case of the fly ash sample bearing a lower level of group I and II ions. These deductions were also supported by DSC data. [ABSTRACT FROM AUTHOR]

Summary: Dynamic and steady shear rheological properties of dynamically vulcanized iPP/EPDM blends were investigated. Two different curing systems based on sulfur or phenolic resin were applied on iPP/EPDM blends. The use of phenolic resin system allows producing materials with lower viscosity at higher rubber content in comparison with sulfur-cured compositions. Melt rheological properties of iPP/EPDM blends with different loading levels of paraffinic oil were studied. Significant improvement in the flowability is observed for TPVs extended with 50 wt% oil. A partial replacement of EPDM on rubber powder decreases the viscosity of materials. [ABSTRACT FROM AUTHOR]

The comparative studies on the thermal, mechanical and morphological behavior of compression molded poly(propylene) (PP)/wood flour (WF) composites were performed using wood flours (WFs) of different origins. The comparison has been made on the basis of results obtained from thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and tensile testing. It has been demonstrated that an addition of 5 wt.-% of maleic anhydride grafted polypropylene (PP-g-MA) has a significant effect on the morphological and thermomechanical behavior of the composites. Although, microscopic examinations revealed no significant differences in the morphology of the compatibilized composites, a remarkable improvement of thermal degradation behavior was observed. From the view point of mechanical properties, the composites with high amount of filler (60 wt.-%) showed similar behavior irrespective of the origin of wood flour. [ABSTRACT FROM AUTHOR]