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The purpose of this paper is to evaluate the efficiency of commercial silica, silica fume-waste (SF) and modified silica fume-waste (mSF) as reinforcing filler in acrylonitrile-butadiene rubber (NBR) and ethylene propylene diene monomer (EPDM) through the mixing process of rubber. The composites were prepared using different loadings of silica fume and commercial silica in EPDM and NBR composites. Structural characterization of silica and SF was done using X-ray fluorescence and scanning electron microscopy (SEM). The surface of silica fume waste was modified using poly methyl methacrylate/butyl acrylate through emulsion polymerization to increase the interaction between silica and rubber, then consequently better dispersion in rubber matrix was obtained. The mSF waste was characterized using FT-IR spectra and transmission electron microscopy.

The investigated rubber mixes and vulcanizates were evaluated by measuring the curing characteristics, mechanical testing, thermogravimetric analysis and morphological studies (SEM). The mechanical properties of composites including tensile strength, elongation at break and modulus were estimated and analyzed.

The results revealed that the composites (NBR and EPDM) containing mSF as filler exhibited better rheological and mechanical properties compared to unmodified silica waste and commercial silica. The SEM analysis indicated that the mSF was homogeneously dispersed through the surface of NBR and EPDM composites. Also, results showed that (NBR and EPDM) composites exhibited remarkable improvements in tensile strength, elongation at break and hardness in the presence of mSF; they also showed an increase in the thermal stability. This means that the treatment of surface SF can improve its dispersion in rubber.

Silica cannot be applied in rubber matrix without surface modification because of their incompatibility; their dispersion is not good without surface modification.

The modified silica surface is considered as effective reinforcing filler which can replace other fillers because of its lower surface energy and enhanced intercalating behavior in rubber.

This study is just a start in establishing rubber projects with wide applications in the industry and providing a cheap local product while preserving the quality and that is the use of factory waste, which helps in protecting the environment from pollution.

mSF is cheap with relatively high purity, which make rubber/mSF composites appear as new grade of material that can be used in different media rather than rubber.

The purpose of this paper is to prepare superabsorbent polymers (SAPs) based on acrylic acid, which is considered hygroscopic material to incorporate in rubber formulation, which results in producing moisten rubber that is used as roofing sheets.

SAPs were synthesized via free radical bulk polymerization technique using different content of cross-linker N, N'-methylenebisacrylamide and potassium persulfate. Differential scanning calorimeter, thermal gravimetric analysis, Fourier transform infrared spectroscopy and transmission electron microscopy were used to characterize SAPs and confirmed the formation of cross-linked hydrogel structure. The water absorbency and the gel fraction for sodium polyacrylate (NaPA) were investigated. Then, the influence of obtained NaPA on the swelling behavior of the prepared natural rubber (NR) compound has been discussed.

Absorption characteristics and gel fraction of NaPA were found to depend on the content of the cross-linker in the system. SAPs are used to improve the absorbance behavior and performance of the NR to produce, roofing sheets using in hot weather. The morphology of the obtained rubber compound was well-explained by using a scanning electron microscope.

The research provides a simple way to produce moisten rubber that can be used as a roofing sheet to overcome warm weather.

Moisten rubber roofing sheets provide a low-cost option in many developing countries with hot climates, and thus, help save the environment from global warming.

This paper aims to study the role of organobentonite (OB) as a filler to improve the mechanical strength of styrene butadiene rubber (SBR). Organoclay was first prepared by modifying bentonite with different concentrations of N-cetyl-N, N, N-triethyl ammonium bromide. A series of SBR composites reinforced with OB were prepared using master-batch method.

The curing characteristics, mechanical properties, thermal behavior, dielectric properties and morphology of SBR/OB composites were investigated.

The elastic modulus and tensile strength of composites were increased by inclusion of OB, while the elongation at break was decreased, due to the increase in the degree of cross-linking density. Thermal gravimetric analysis revealed an improvement in the thermal stability of the composite containing 0.5 cation exchange capacity (CEC) OB, while the scanning electron micrographs confirmed more homogenous distribution of 0.5CEC OB in the rubber matrix. Also, SBR/0.5CEC OB showed low relative permittivity and electrical insulating properties.

Bentonite has been recognized as a potentially useful filler in polymer matrix composites because of their high swelling capacity and plate morphology.

OB improves the cured rubber by increasing the tensile strength and the stiffness of the vulcanizate.

Using cheap clay in rubber industry lead to production of low cost products with high efficiency.

The clay represents a convenient source because of their environmental compatibility. The low cost and easy availability make the modified clay used as fillers in rubber matrices, and the resultant composites can be applied in variety industrial of applications such as automobile industries, shoe outsoles, packaging materials and construction engineering.