Oil-absorptive polymeric nanocomposites were prepared through the melt blending of soft oleophilic ethylene-propylene-diene monomer and stearyl acrylate as a hydrophobic monomer in the absence and presence of different loadings of untreated and oleophilized laponites with quaternary ammonium salts of n-alkylamines of different chain lengths (C10, C12, and C16) with dicumyl peroxide as a vulcanizing agent. The samples were then vulcanized at 152 C according to the determined rheometric characteristics to produce nanocomposite vulcanizates of an exfoliated type with limited cavities as revealed by X-ray diffraction and scanning electron microscopy. The produced vulcanizates were evaluated as oil-absorptive polymeric networks and proved to be efficient oil sorbents of moderate activity. The oil absorptivity was examined with respect to the stearyl acrylate grafting, the types of oleophilizing agents of clay in comparison with the bare clay, and the clay loading and crosslink density.

Two different nano‐emulsions based on methyl methacrylate/butyl acrylate copolymers have been synthesized to be used as retanning and lubricating agents for chrome‐tanned leather. The main difference and characteristics of the two prepared copolymers were studied. The nano particle size of the two copolymers was confirmed using transmission electron microscope (TEM). The influence of the prepared copolymers on chrome‐tanned leather as retanning agents was investigated. The properties of the retanned leather, namely, physicomechanical properties as tensile strength, elongation at break and water absorption, were measured. Thermal gravimetric analysis (TGA) technique was used to examine the thermal stability of the retanned leather. Also, the texture of the grain surface and fibers were inspected using scanning electron microscope (SEM). The retanned leather showed an improvement in its physicomechanical properties, as well as enhancement of its thermal stability as compared with the chrome‐tanned leather. Furthermore, the retanned leather has uniform dyestuff, softness, and firmness of grain. All these promising results provide evidence to the applicability of the prepared copolymer emulsions as efficient retanning and lubricating agents for chrome‐tanned leather. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The effect of type, length, and denier of fibers on the thermal stability and swelling behavior of chloroprene/ butadiene-acrylonitrile rubbers (CR/ NBR) composites was investigated. The results reveal that Nylon 6 fibers improved mechanical properties, thermal stability, and swelling resistance in toluene of 50/50 CR/ NBR blends. Of all fiber types investigated, the viscose fiber CR/ NBR composite has the best swelling resistance in motor oil, whereas the polyester (PET) fiber composite has the best swelling resistance in brake fluid. The effect of Nylon 6 fiber loading up to 30 phr was tested in terms of mechanical properties of the composites and swelling in toluene and oils. Also, the reinforcement of white-filled blends were examined. Nylon 6 fiber loadings (15-30 phr) showed promising results, and the white-filled Nylon 6 composites showed a significant reinforcement with regard to mechanical properties and thermal stability.

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The graft copolymerization of 2-dimethylamino ethylmethacrylate (DMAEMA) onto ethylene propylene diene mononer rubber (EPDM) was carried out in toluene via solution polymerization technique at 70 C, using dibenzoyl peroxide as initiator. The synthesized EPDM rubber grafted with poly[DMAEMA] (EPDM-g-PDMAEMA) was characterized with 1 H-NMR spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The EPDM-g-PDMAEMA was incorporated into EPDM/butadiene acrylonitrile rubber (EPDM/NBR) blend with different blend ratios, where the homogeneity of such blends was examined with scanning electron microscopy and DSC. The scanning electron micrographs illustrate improvement of the morphology of EPDM/NBR rubber blends as a result of incorporation of EPDM-g-PDMAEMA onto that blend. The DSC trace exhibits one glass transition temperature (T g ) for EPDM/NBR blend containing EPDM-g-PDMAEMA, indicating improvement of homogeneity. The physico-mechanical properties after and before accelerated thermal aging of the homogeneous, and inhomogeneous EPDM/NBR vulcanizates with different blend ratios were investigated. The physico-mechanical properties of all blend vulcanizates were improved after and before accelerated thermal aging, in presence of EPDM-g-PDMAEMA. Of all blend ratios under investigation EPDM/NBR (75/25) blend possesses the best physico-mechanical properties together with the best (least) swelling (%) in brake fluid. Swelling behavior of the rubber blend vulcanizates in motor oil and toluene was also investigated. V