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The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

In the present work, under severe conditions of an inert atmosphere and high temperature, epoxidized natural rubber (ENR) with 25 per cent epoxidation level reacts with different aliphatic amine compounds such as ethyl amine (EA), propyl amine (PA) and butyl amine (BA) to prepare ENR/EA, ENR/PA, ENR/BA compounds as, respectively. The produced compounds were characterized by Fourier transform infrared spectroscopy and oxirane oxygen content determination. Different concentrations of the produced compounds were added to epoxy and urethane acrylate coating formulations to evaluate them as corrosion inhibitors for mild steel under UV irradiation. Corrosion resistance tests and weight loss measurements of the coated steel panels were made. It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion, and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors which give the best inhibition efficiency for corrosion are 0.4-0.6 phr.

Corrosion scratch tests were carried out according to ASTM D 1,654-92 (2000). The weight loss of coated steel was measured according to ASTM D 2,688-94 (1999). The measurement of film hardness was carried out with a Wolff–Wilborn pencil hardness tester according to ASTM D 3,363 (2000).

It was found that coating formulations containing the prepared ENR/EA compound could protect metal surface from corrosion and corrosion inhibitors efficiency of the prepared compounds were arranged as follows: ENR/EA > ENR/PA > ENR/BA. The optimum concentrations for all inhibitors are 0.4-0.6 g/100g coating.

A highly efficient and economically corrosion inhibitors for mild steel were prepared from ENR and series of aliphatic amines.

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.

This paper aims to study the effects of various compatibilisers (maleic anhydride (MAH), methyl methacrylate/butyl acrylate emulsion lattice, and adhesion system (HRH)) on properties of carbon black (CB) filled with natural rubber (NR)/styrene-butadiene rubber (SBR)/ nitrile butadiene rubber (NBR) blends). A series of NR/SBR/NBR blends at a 30/30/40 blend ratio reinforced with 45 phr of CB was prepared using the master-batch method.

The tensile properties such as the tensile strength, stress at 100, 200 and 300% elongations, and elongation at break (EB)% were studied. Additionally, the morphological properties of compatibilised and uncompatibilised composites were compared to determine the optimal compatibiliser content.

The influence of compatibilisers appeared on all the properties studied. The properties of the blends compatibilised with prepared emulsion are very distinct from those of blends compatibilised with MAH and adhesion systems.

Interactions among the different components of blends at the interfaces have a high impact on the interfacial properties of the rubber blend.

Compatibilisers significantly improve the physicomechanical properties of the resulting composites with the loading of investigated compatibilisers because of the uniform dispersion of CB in the rubber matrix.

Using blends in the rubber industry leads to high-efficiency production of low-cost products.

The rubber blending has a significant positive effect on a wide range of applications such as structural applications, aerospace, military, packaging, tires and biomedical. Hence, improving the compatibility of blends will make new materials suitable for new applications.

This study aims to investigate the swelling behavior, mechanical and thermal properties of ternary rubber blend composites prepared by melt blending based on carbon black (CB)-filled natural rubber (NR)/styrene-butadiene rubber (SBR)/nitrile butadiene rubber (NBR) blends, containing a variety of compatibilizers. Various compatibilizers, maleic acid anhydride (MAH), prepared emulsion and adhesion system (HRH) were used. A series of NR/SBR/NBR blends at a 30/30/40 blend ratio reinforced with 45 phr of CB were prepared using the master-batch method.

Thermal aging properties of the composites characterized by their aging coefficient and retention in tensile and elongation at break (E.B. %). Thermal degradation of ternary rubber blend composites based on melt blending has been studied using thermogravimetric analysis.

The swelling coefficient decreased with increased compatibilizer loading. Results also showed that the tensile strength and E.B. (%) decreased with aging over the entire aging period. Additionally, the addition of compatibilizers into the ternary rubber blend composite had slightly improved the thermal stability.

Interactions between the different components of blends at the interfaces have a high impact on the interfacial properties of the rubber blend.

Compatibilizers significantly improve the properties of the resulting composites with the loading of investigated compatibilizers because of the uniform dispersion of CB in the rubber matrix.

Using blends in the rubber industry led to the high-efficiency production of low-cost products.

The rubber blending has a significant positive effect on a wide range of applications such as structural applications, aerospace, military, packaging, tires and biomedical, so improving the compatibility of blends will make new materials suitable for new applications.

The main aim of this study was to examine the effects of chicken eggshell (CES) and rice husk ash (RHA) as fillers on the mechanical and the thermal insulation properties of polyurethane coatings.

CES and RHA were ground via ball milling set at different parameters, and the smallest particles size obtained were selected and used as fillers. Fillers of different weight proportions were mixed with other components such as binder, solvent and pigment to form various coating formulations and test samples were made via dip coating. A series of characterisations were conducted to analyse the thermal and mechanical properties of the coating.

The smallest particle size of CES and RHA was obtained after both of them had undergone grinding process at 400 rpm within 180 min. Morphological studies revealed that CES and RHA have irregular shape and high porosity. In crystallographic analysis, CES mainly composed of pure calcite crystal structure and RHA contained amorphous silica. Both of fillers were found thermally stable up to 520 and 710°C for RHA and CES, respectively. In RHA individual system, as the RHA proportion increases, the thermal conductivity of the coating declined. In contrast, in the CES coating system, the thermal conductivity demonstrated an opposite trend. Thermal gravimetric analysis results displayed that by adding hybrid fillers, the residue weight and the thermal stability of the coatings were increased. In addition, the adhesion strength of the coating was increased as the filler weight content increased.

Fillers with nano-range size were expected to be produced in this research for better performance of the coating. However, the obtained fillers were limited to micron size through dry grinding method. Another drawback in this research was the coating technique which is dip coating. The coated substrates do not have uniform coating thickness and this subsequently influenced the performance.

A novel attempt has been made to study the formulation coating system by mixing CES and RHA as fillers which is also known as a hybrid system.