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Blends of polypropylene (PP) and acrylonitrile butadiene rubber (NBR) were prepared with different weight compositions with a plasticorder at 180 C at a rotor speed of 60 rpm for 8 min. The physicomechanical properties and mass swell of the prepared blends were investigated with special reference to the effects of the blend ratio. The prepared epoxidized linseed oil (EL) (i.e., E 0.5 L, E 1 L, E 1.5 L, and E 2 L using 0.5, 1, 1.5, and 2 mol H 2 O 2 /mole of unsaturation in linseed oil) and maleic acid anhydride (MAH) were melt mixed in various contents (i.e., 1, 5, 10, and 15 wt %) with a PP/ NBR blend with a weight ratio of 70/30 and used as compatibilizers. The effect of the compatibilizer contents on the physicomechanical properties and mass swell of the binary blend was investigated. With an increase in the compatibilizer content up to 10 wt %, the blend showed an improvement in the physicomechanical properties and reduced mass swell in comparison with the uncompatibilized one. The addition of a compatibilizer beyond 10 wt % did not improve the blend properties any further. The efficiency of the compatibilizers (10 wt %) was also evaluated by studies of phase morphology (scanning electron microscopy). EXPERIMENTALMaterials PP (isotactic) [Moplen EP-D60R, product of Montell Polyolefins, Italy] with a melt flow index ¼ 0.35 g/ Correspondence to: E. M. Sadek (elham_sadek@hotmail. com).

Modification of the Egyptian Bentonite (EB) was carried out using organo-modifier namely; octadecylamine ODA. Before the modification, the cation exchange capacity (CEC) of the EB was measured, also it was purified from different impurities using HCl and distilled water. The Organo-bentonite OB was characterized using IR, XRD, and TEM. PU/ODA-B nanocomposites were prepared by in situ polymerization then characterized by XRD and TEM. An amount of ODA-B ranging from 0.25% up to 5% by weight was added to the polyol component of the resin before mixing with toluene diisocynate TDI. TEM showed that the nanocomposites achieved good dispersion in the polyurethane matrix. The mechanical, swelling and electrical properties of the nanocomposites were measured. The results indicate that the tensile strength of all the nanocomposites enhanced with the addition of OB compared with the pure PU. The crosslink density of the nanocomposites increases with increasing the content of OB. The Pool-Frenckel conduction mechanism predominates for all the nanocomposite samples and the blank one. ª 2014 Production and hosting by Elsevier B.V. on behalf of Egyptian Petroleum Research Institute.

Titanium dioxide hollow spheres were synthesized by utilizing polystyrene-co-methacrylic acid latex particles coated with titanium isopropoxide. Hollow spheres prepared with different ruthenium salt concentrations showed considerable levels of organic pollutant degradation upon UV irradiation. In the present study, methylene blue (MB) was selected as a model for these pollutants. Thus its degradation indicated the activity of the hollow spheres as photocatalysts for decomposing the pollutants. The efficiencies of these photocatalysts were determined in terms of chemical oxygen demand removal. During these experiments, several conditions were monitored such as the effects of pH, ruthenium salt concentration, and initial MB load concentration. The prepared particles were characterized by using transmission electron microscopy and scanning electron microscopy.

The effect of hexamine (HA) addition on the morphological, thermal, mechanical, and dielectric properties of acrylonitrile butadiene rubber (NBR) composites has been considered. In this regard, HA was composited with NBR in different part percentages. The prepared formulations were characterized by using ATR-FTIR and mapped with AFM for their topographical features which revealed multiple protrusions and showed that HA was distributed in the form of clustered crystals on the rubber surface and within the rubber matrix. The investigated data revealed that the tensile strength, elongation, and shore A hardness were improved with addition and increasing HA ratio till 50 phr then reneged. The thermal gravimetric analysis (TGA)showed a graduated decreasing effect on the thermal stability by addition of HA. Moreover, upon increasing the proportion of HA in the composite, the electrical resistivity was dropped by several orders of magnitude at a critical filler concentration. The conductivity through composite material is described as a transport mechanism that involves electrons tunneling through the gaps founded in between of the two discontinuous conducting elements and a continuous conducting network forming. Experimental and calculated values of electrical resistivity showed close similarity only at higher HA loading ratios.

The main component of rosin natural gum is abietic acid, which has an interesting chemical structure to be studied with the influence of gamma-ray and the antimicrobial activity on the properties of a cheap abundant solid state natural material of rosin. Rosin is exposed to a wide scale of gamma-ray ranges from 0 to 100 kGy. The changes in the properties are tracked by various techniques of FTIR, XRD, TGA, GPC, and SEM. The molecular weight of rosin changes from 370 g/mol to higher and the morphological properties were investigated. The irradiated rosin acid (IRA) at different irradiation doses exploited antimicrobial effect versus Gram-positive and Gram-negative as well. The inhibition zone enhanced from 15 to 33, 14 to 28, 14 to 20, and 9 to 14 mm for Gram-positive and Gram-negative, respectively. Moreover, bioactive behavior for irradiated rosin of 40 kGy recorded the highest antibacterial activity against both types of bacteria. The outcome data of antimicrobial activity are good and confirm that there is a significant effect of irradiation dose on the biocidal activity of rosin.

The subsequent activated carbons of resorcinol-formaldehyde xerogels are synthesized and exposed to wide range of gamma irradiation dose. Xerogels and their subsequent activated carbons are characterized by diverse techniques; FTIR, Raman, porosity analysis, SEM, EDX and AFM. The composite membranes are fabricated from polyacrylonitrile and activated carbon xerogels as composite membranes to be utilized in ultrafiltration process of salted oily wastewater. The soybean oil is exploited as organic feeding solution. The results declared that values of flux and rejection reach 157 (L m−2 h−1) and 99.8 (%), respectively. Overall, the best performing composite membrane is conducted by maximizing pure water flux. The optimally synthesized membrane performs well for purification of salted oily wastewater, and a significant increment in permeate flux is obtained with soybean oil rejection is at ∼99.8% and with maximum flux is at 32 (L m−2 h−1). Further, the composite membranes showed good promise for ultrafiltration of salted oily wastewater.

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