bisphenol-A Type Research Articles

Nanocomposites based on MWCNT and nanoclay: Effect of acrylated epoxidized soybean oil on curing and composite properties

UV and thermal-curing hybrid epoxy adhesives are generally developed with a combination of epoxy acrylates and thermal-curing epoxy resin. This study modified bisphenol-A type epoxy resin (ER) with acrylated epoxidized industrial crop soybean oil (AESO) to obtain a dual-curable epoxy system. Hydroxylated multi-walled carbon nanotube (MWCNTOH) and montmorillonite-type nanoclay (NC) first was used as nano reinforcement in this system. Both thermal and UV-curing were applied to composites. Tensile and hardness tests, thermogravimetric analysis (TGA), and four-point probe electrical conductivity measurements were used for the nanocomposite characterization. Although (UV+thermal) curing increased the thermal strength of the nanocomposites, it caused a decrease in their electrical conductivity and moisture absorption. The highest tensile strength values were obtained as 107 MPa and 97 MPa for thermally cured 1.5 wt% MWCNTOH and 2 wt% NC composites, respectively. The effect of the AESO ratio on UV curing of nanocomposites was investigated and 10 % was found to be the most suitable. MWCNTOH composites also exhibited the highest electrical conductivity with a percolation threshold of 1.5 wt%. The effect of hydrothermal aging on thermal and electrical conductivity properties showed that only T5 and T10 values of thermally or (UV+thermally) cured MWCNTOH and NC composites decreased, T50 values did not change significantly.

Preparation and properties of fiber-reinforced polybenzoxazine composite aerogels based on freeze drying and ambient pressure drying methods

Polybenzoxazine aerogels have gained much attention as a new type of polymeric aerogels in the field of flame resistant materials. Herein, a unique method for the preparation of fiber-reinforced PBa composite aerogels has been reported using polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) as dispersion carriers through freeze-drying for surface modified basalt fibers (Z@BF). Bisphenol-A type benzoxazine (Ba) monomer was used as the matrix, which infiltrated into the carrier for dispersed fibers to obtain a PBa composite gel by sol-gel method. Solvent exchange and ambient drying techniques were used to obtain the final composite aerogel samples. Z@BF formed a double-network structure with the aerogel matrix, which resulted in 55.43% increase in compressive strength, a low volumetric shrinkage (27.46%), and density (0.19–0.21 g cm3) of the prepared aerogel. The addition of Z@BF increased the residual carbon content (59.6% at 800 °C) in the aerogel, while reducing the total heat release rate by 36.9% and the peak heat release rate by 60.61%. Besides, the aerogels possessed excellent self-extinguishing property, and the self-extinguishing time was only 1.31 s after flame burning at 1200 ℃ for 10 s. The composite aerogels obtained by this combination of atmospheric pressure drying and freeze-drying techniques not only possessed high mechanical strength and excellent flame retardant properties, but also provided a new idea for the preparation of fiber-reinforced PBa aerogels. This would further expand the potential use of PBa aerogels in flame retardant materials.

Reusing Bisphenol—A Type of Epoxy Polymer Recyclates from the Solvolysis of CFRP

Carbon fiber-reinforced polymer (CFRP) composites are highly functional composites which comprise two major components: the polymer matrix and the carbon fiber. Lightweight and having high strength, CFRPs have been used heavily in various industries such as wind, aerospace and automobile. The increasing demand and extensive use led to a huge quantum of CFRP waste from both end-of-life and during manufacturing. Out of this waste, only 2% is recycled, the rest are disposed of via incineration and/or landfill. This has raised significant environmental and sustainability concerns. The current state-of-the-art way of recycling CFRPs is by pyrolysis. However, through the pyrolysis process, the polymer used in the CFRPs, which accounts for around 65–75 wt.%, cannot be recovered and reused. In most publications, the focus on CFRP recycling was on the recovering of the more valuable carbon fiber. The polymer matrix is mostly burnt off, in the case of pyrolysis, or disposed. To obtain full circularity, recovering and reusing both the carbon fiber and polymer is necessary. In this paper, we primarily focus on the recovered bisphenol-A type of epoxy polymer (REP) obtained from solvolysis digestion of CFRP and explore the feasibility of reusing this REP by blending it with pristine epoxy in various compositions to create new materials. The physical and mechanical properties, including decomposition temperatures (Td), glass transition temperatures (Tg), storage modulus, loss modulus, flexural and tensile strength, were characterized using thermal gravity analyzer (TGA), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA) and Instron universal tester. The results indicate a decrease in glass transition and decomposition temperature, and mechanical properties as the blending composition increases. This suggests that the total blending composition should not exceed 10 wt.%, with an optimal range potentially falling between 5 to 6 wt.%.

Implementation of the PECVD process to produce a novel range of filler-polymer-coated perlites for use in epoxy composites

This study examines the use of expanded perlite powder (ExP), a natural rock, as reinforcement in bisphenol-A type epoxy resin. The surface of ExP has been coated using the PECVD method with different polymers such as poly(hexafluorobutyl acrylate) (PHFBA) and poly(glycidyl methacrylate) (PGMA). ExPs before and after the coating process underwent characterization using various techniques such as X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Scanning Electron Microscopy (SEM). The effects of filler ratio and different polymer coatings on composite properties were investigated. The higher tensile strengths for uncoated, PHFBA-coated, and PGMA-coated ExP composites were determined as 109 MPa, 132 MPa, and 152 MPa, respectively. The surfaces of the polymer-coated ExP composites were found to be hydrophobic and water sorption was lower in these composites. ExPs have improved thermal stability and flammability properties. In addition, PHFBA-coated ExP composite was found more resistant to UV radiation and the hydrothermal environment.

Synergistic Effect of Nanoparticles: Enhanced Mechanical and Corrosion Protection Properties of Epoxy Coatings Incorporated with SiO2 and ZrO2.

This research paper presents the fabrication of epoxy coatings along with the hybrid combination of SiO2 and ZrO2. The epoxy resin is incorporated with SiO2 as the primary pigment and ZrO2 as the synergist pigment. The study delves into the adhesion, barrier, and anti-corrosion properties of these coatings, enriched with silica and zirconium nanoparticles, and investigates their impact on the final properties of the epoxy coating. The epoxy resin, a Diglycidyl ether bisphenol-A (DGEBA) type, is cured with a polyamidoamine adduct-based curing agent. To evaluate the protective performance of silica SiO2 and zirconia ZrO2 nanoparticles in epoxy coatings, the coated samples were tested in a 3.5% NaCl solution. The experimental results clearly demonstrate a remarkable improvement in the ultimate tensile strength (UTS), yield strength (YS), and Elastic Modulus. In comparison to using SiO2 separately, the incorporation of both ZrO2 and SiO2 resulted in a substantial increase of 43.5% in UTS, 74.2% in YS, and 8.2% in Elastic Modulus. The corrosion test results revealed that the combination of DGEBA, SiO2, and ZrO2 significantly enhanced the anti-corrosion efficiency of the organic coatings. Both these pigments exhibited superior anti-corrosion effects and mechanical properties compared to conventional epoxy coatings, leading to a substantial increase in the anti-corrosion efficiency of the developed coating. This research focuses the potential of SiO2 and ZrO2 in hybrid combination for applications, where mechanical, corrosion and higher adhesion to the substrates are of prime importance.

Evaluation of EPDM waste in environmentally friendly epoxy hybrid composites

This study aims to reduce the production cost of composite materials, obtain composite materials with improved properties, and expand the applications of waste rubber composites using two different industrial wastes, ethylene-propylene-diene monomer rubber (EPDM) and tire waste pyrolysis solid product carbon black (CB). Composites were formed by adding EPDM waste or EPDM-CB mixture at 1:1, 1:3, and 3:1 ratios to bisphenol-A type epoxy resin in different weight ratios. Mechanical, water sorption, electrical conductivity, and flammability tests were applied to the composites. The effect of the EPDM:CB ratio and some environmental conditions on the mechanical properties of the hybrid composites were investigated. Composites with 3:1 weight ratio of EPDM:CB had the highest tensile strength, which varied between 115.5–158.6 MPa. Increasing the EPDM ratio in an epoxy matrix and hybrid filler decreased the composites’ density and tensile strength. EPDM-CB hybrid filler increased the thermal strength of epoxy. Mechanical properties are affected by water sorption, low temperature, and UV irradiation. Increasing the CB ratio in the hybrid filler decreased the flammability of the hybrid composites. ANOVA is applied to find the significant effect of different weight percentages of hybrid fillers and different varieties of fillers on the mechanical properties of composites.

Highly dispersed aramid nanofiber-reinforced epoxy nanocomposites by the sequential solvent-exchange method

Aramid nanofibers have recently been used as novel reinforcing materials to overcome the limitations of epoxy resin because of their superior strength and toughness. Until now, aramid nanofibers were hybridized into the epoxy resin by adding water into an aramid nanofiber solution to obtain free-standing powders. Unfortunately, such a water-based method for inducing the gelation hinders high-level dispersion due to the re-agglomeration of the nanofibers by protonation. This study presents a novel technique utilizing a solvent-exchange method to maximize the dispersion degree of aramid nanofibers, thereby increasing the mechanical properties of epoxy nanocomposites. The mechanical properties of aramid nanofiber-reinforced epoxy nanocomposites by the solvent-exchange method were improved significantly (3.4 GPa in Young’s modulus and 90.0 MPa in tensile strength – improvements of 28.8% and 27.7%, respectively) although a high viscosity epoxy resin (bisphenol-A type) was considered. Therefore, the suggested solvent-exchange method is an efficient manufacturing process to produce highly dispersed aramid nanofiber/epoxy nanocomposites.

Characterization and modelling of bisphenol-a type epoxy polymer over a wide range of rates and temperatures

Epoxy resins are employed in many engineering applications in which mechanical properties at different strain rates and temperatures must be quantified for effective use. It is known that these properties are related through the principle of time-temperature equivalence. In this paper, the application of this equivalence is explored in detail, at both small and large strains, and used as part of a strategy for calibrating a constitutive model that can reproduce the stress-strain behaviour in different mechanical conditions. In order to achieve this, quasi-static compression experiments were performed at temperatures from −40 to +40 °C in a screw-driven load frame; room temperature rate dependent experiments were performed from 0.0005 to 6300 s−1 using a screw-driven load frame, hydraulic compression system and Split Hopkinson Pressure Bar apparatus. Dynamic mechanical analysis and differential scanning calorimetry were also performed. A three-network (TN) polymer model was fit to the mechanical behaviour up to a strain of 0.5. This model, combined with time-temperature based mappings gave a good understanding of the thermomechanical behaviour of the material, and also demonstrates an approach that can be used for a wide range of polymers.

A Phosphorous-Containing Bio-Based Furfurylamine Type Benzoxazine and Its Application in Bisphenol-A Type Benzoxazine Resins: Preparation, Thermal Properties and Flammability.

Polybenzoxazine (PBa) composites based on phosphorous-containing bio-based furfurylamine type benzoxazines (D-fu) and bisphenol-A type benzoxazines (Ba) were developed for flame retardation. The structure of D-fu was analyzed by Fourier transform infrared (FTIR) spectroscopy and 1H-NMR spectroscopy. The curing temperature of Ba/D-fu mixtures was systematically studied by differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) demonstrated the excellent char formation ability of the PBa composites with the addition of phosphorous-containing D-fu. The flame retardancy of the PBa composite materials was tested by the limited oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter (CONE). The LOI and UL-94 level of PBa/PD-fu-5% reached 34 and V0 rate, respectively. Notably, the incorporation of 5% D-fu into PBa led to a decrease of 21.9% at the peak of the heat-release rate and a mass-loss reduction of 8.0%. Moreover, the fire performance index increased, which demonstrated that the introduction of D-fu can diminish fire occurrence. The role of D-fu in the condensed and gas phases for the fire-resistant mechanism of the PBa matrix was supported by SEM-EDS and TGA/infrared spectrometry (TG-FTIR), respectively. Dynamic mechanical analysis (DMA) revealed that the Tg of PBa flame-retardant composites was around 230 °C. Therefore, PBa composites are promising fire-retardant polymers that can be applied as high-performance functional materials.

Corrosion Resistance Synergistic Appraisal of Titanium-Impregnated Bisphenol A-Type Epoxy Duplex Coating System in Stimulated and Natural Marine Environments of Southeastern Coastal Area of China–Pakistan Economic Corridor

This research endeavor is aimed at developing a protective coating for marine service conditions of the southeastern coastal area of the China–Pakistan Economic Corridor. Bisphenol A-type epoxy-based protective coatings were prepared by impregnating exotic titanium metal microparticles into two different proportions, i.e., 5% and 10% (w/w). Film hardness measurement by pencil test, adhesion measurement by the crosshatch-tape test, chemical and heat resistance test, gloss measurement, natural exposure, and salt spray testing have demonstrated that Ti-enriched coatings have performed better than the virgin epoxy coating. Moreover, scanning electron microscopy has depicted more surface degradation. Fourier transform infrared spectroscopy has indicated higher mass loss and chain scission in the virgin epoxy coating than the Ti-enriched coatings. In addition, these Ti microparticles have filled up the cavities/imperfections, reduced cracking, promoted crosslinking during the curing, and cordoned-off passage of corrodents and moisture, thus improving epoxy resin coating features. These results have widened the scope of Ti-embedded epoxy coatings against atmospheric corrosion for highly corrosive marine sites.

Study on cryogenic mechanical properties between superconducting wires and resins for MRI superconducting magnet

Superconducting magnet is a key component in magnetic resonance imaging (MRI). In general, vacuum pressure impregnation (VPI) technology is used for insulating system of the superconducting magnet. Performance of the superconducting magnets is affected by the adhesion strength between superconducting wires and resins at cryogenic temperature. In this study, experimental superconducting coil was prepared by modified bisphenol-A type epoxy resin and the VPI technology. Tensile, shear, and compressive properties of the samples cut from the superconducting coil were measured at both room temperature (RT) and liquid nitrogen temperature (77 K), and the bonding properties between the superconducting wire and the resin were discussed. The results show that the resin exhibits low viscosity, long pot life and higher mechanical strength, and it is suitable for impregnating superconducting magnets by VPI technology. Moreover, the shear and compressive strength of the impregnated superconducting magnet at 77 K are significantly higher than that at room temperature, with the increase of 132% in radial compressive strength, 170% in axial compressive strength, 63% in radial shear strength and 70% in axial shear strength, respectively. This study provides references for the design of insulation for superconducting magnet system and the manufacture of insulating materials for MRI superconducting magnets.

Evaluation of the Mechanical Properties of Polyether Sulfone-Toughened Epoxy Resin for Carbon Fiber Composites

Polyether sulfone (PES), which is a thermoplastic polymer, was added as a toughening agent to a bisphenol-A type epoxy resin to form a matrix of carbon-fiber-reinforced composites (CFRPs). For benchmarking, carboxyl-terminated butadiene acrylonitrile (CTBN), which is a rubber-based toughening agent, was added to the epoxy resin. The mechanical and thermal properties of the PES- and CTBN-toughened epoxy resins were compared. Dicyandiamide (DICY) was used as the hardening agent, whereas 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) was used as the hardening accelerator. In addition, 4,4′-diamino diphenyl sulfone (DDS) was added to improve the dispersibility of PES in the epoxy resin. The CTBN-toughened epoxy resin exhibited improved impact strength and fracture toughness, but decreased tensile strength, tensile modulus, and glass transition temperature (Tg). The fracture toughness and Tg values of the PES-toughened epoxy resins increased with increasing amount of added PES. However, the tensile moduli and Tg values of the epoxy decreased upon addition of CTBN. The tensile and impact strengths of the specimen toughened with 10 phr PES increased by 14 % and 106 %, respectively, compared to those of the PES un-toughened epoxy resin. The ductility factor of the resin improved with increasing PES content. CTBN formed microvoids and CTBN particles within the epoxy matrix, which improved the fracture toughness of the resin, but deteriorated its tensile properties by stress concentration. In contrast, PES improved the properties of the epoxy resin. This was attributed to PES being well dispersed within the epoxy matrix, thereby absorbing the energy required for crack propagation. Hence, owing to their excellent mechanical properties, the PES-toughened epoxy resins were determined suitable for use as matrices for CFRPs.

Investigation into the tensile properties of ISO-401 double-thread chain-stitched glass-fibre composites

Interlaminar stitching has proven to be an effective through-thickness reinforcement technique for laminated composites but a major drawback is the negative effect it has on the in-plane tensile properties. This study aims to optimise stitching for composites to reduce the associated negative effects by introducing a new stitch type to composite laminates. The double-thread chain-stitch (ISO-401) has shown great utility in the textile industry but has not yet been applied as through-thickness reinforcement to composites. In this paper, tensile properties of glass fibre composite laminates stitched with ISO-401 double-thread chain stitch have been examined, as stitching reduces in-plane strength while improving damage tolerance. Three variations of the ISO-401 geometry were employed by varying the stitch junction position and each position was applied at two stitch densities by varying the stitch pitch at 3 mm and 4 mm. The composites were manufactured using E-glass 2 × 2 twill fabric and a Bisphenol-A type epoxy resin, stitching was performed with core-spun tex 24 polyester thread. The experimental data demonstrated the influence of ISO-401 junction position and stitch density on the composite tensile properties. Furthermore, adjustment of the junction position was found to affect the size of stitch-induced resin pockets and severity of in-plane fibre misalignment.

Comparative study of the ideal and actual adhesion interfaces of the die bonding structure using conductive adhesives

ABSTRACT A die bonding interface consisting of a plated gold surface and conductive silver paste was investigated using two approaches: One was a computational method for the ideal interaction, while the other was an experimental technique to get some ideas about the actual bonding. A density functional theory (DFT) calculation was employed to clarify the adhesive interface between the Au (1 1 1) surface and bisphenol-A type epoxy resin which included dicyandiamide as a curing agent. The computational results showed that the cyano group involved in the hardener strongly binds to a gold atom on the ideal surface. This interaction is likely to be assigned to σ-donation and π-back donation. The predicted adhesive strength was 1.15 GPa. To evaluate the real adhesion strength, small-sized single lap-shear joints were fabricated and tensile shear tests were performed. The measured adhesive stress was about 27 MPa. The results of surface analytical methods indicated that the actual die pad surface was not smooth. Furthermore, an altered layer terminated with Au(CN)x was found on the top of the die pad. It was inferred that the mechanism of the actual die bonding interaction would be changed to the formation of hydrogen bonds. This could be a reason why reduced adhesive strength was observed.

Deformability of Bisphenol A-Type Epoxy Resin-Based Polymer Concrete with Different Hardeners and Fillers

This study experimentally investigated the deformability characteristics of bisphenol A-type epoxy resin-based polymer concrete produced using two types of hardener and four types of filler. In particular, the basic properties of epoxy resin polymer concrete, including the modulus of elasticity, setting shrinkage, and thermal expansion, were experimentally investigated to obtain basic data for evaluating compatibility and dimensional stability. The properties of the epoxy resin polymer concrete were determined when different types of hardener and filler were employed. Differences in deformability can be identified based on these properties. In the present study, the setting shrinkage, coefficient of thermal expansion, and modulus of elasticity were lowest when fly ash was employed as one of the four fillers. Hence, it is advantageous to use fly ash as a repair material for ordinary Portland cement concrete structures. Therefore, the results of this study will be helpful when selecting the types of hardener and filler needed to tailor the epoxy resin polymer concrete produced to be suitable for a particular application.

Polymer composites based on epoxy resin with added carbon nanotubes

Epoxy resin (diglycidyl ether bisphenol-A type) polymer composites with added pristine and fluorinated carbon nanotubes (CNTs) were studied by FTIR, TGA and electron microscopy. The tensile and flexural strengths of these composites were measured. The specific surface value of the fluorinated CNTs was found to be about 2.26 times higher than that of the one containing the pristine CNTs. The fluorination did not affect the thermal stability of the CNTs below 260 °C and did not worsen the thermal stability of the filled composites. The introduction of 0.1 wt% CNTs fluorinated at 150 °C into the polymer matrix resulted in the increase of the tensile strength of the composite to 89.6 ± 4.1 MPa (35% increase when compared to the unfilled composite). The flexural strength of the composite filled with 0.2 wt% CNTs fluorinated at 150 °C was increased to 199.7 ± 4.8 MPa (+58% when compared with the unfilled composite). The pristine CNTs were less effective in improving the tensile and flexural strengths of the composite when compared with the fluorinated CNTs. The introduction of the fluorinated CNTs into the polymer matrix did not influence the thermal stability of the composite. The reinforced composites can be applied in several areas: aviation, automotive, wind turbine propeller blades, for producing yachts and boats, etc.

Hydrogenation of Bisphenol A-Type Epoxy Resin (BE186) over Vulcan XC72-Supported Rh and Rh–Pt Catalysts in Ethyl Acetate-Containing Water

This study demonstrates the hydrogenation of a bisphenol A-type epoxy resin (BE186) through solvent selection, development of a catalyst for aromatic ring hydrogenation, and control of epoxy loss. ...

Synergistic Effect of Ag and ZnO Nanoparticles on Polypyrrole-Incorporated Epoxy/2pack Coatings and Their Corrosion Performances in Chloride Solutions

In this study, two formulae (F1 and F2) of epoxy/2pack coatings incorporated with polypyrrole (PPy)-conducting polymer were produced from bisphenol-A type of epoxy resin (DGEBA) with the addition of Ag and ZnO nanoparticles. The synergism effect of Ag and ZnO nanoparticles on the mechanical and corrosion resistance properties was reported. The curing agent 2,4,6-tris (dimethylaminomethyl) phenol (ARADUR 3282-BD) was used under optimized stoichiometry values. The nanoparticles ratio in different wt.% were first dispersed in solvent by the sonication process and then added to epoxy/PPy composition. All the coated steel panels were cured at room temperature in a controlled dust free environment for 7 days in order to obtain a hard and intact coating. The dispersion of nano-size ZnO and Ag pigments was investigated using scanning electron microscopy (SEM) and its composition through an energy dispersive X-ray (EDX) technique. Conventional techniques and nano-indentation were also performed to observe the effect of ZnO and Ag synergism content on the hardness and modulus of elasticity at nano scale. The corrosion behavior of the coated samples was investigated at room temperature in 3.5% NaCl solution using electrochemical impedance spectroscopy (EIS). The synergism effect of nanoparticles along with PPy resulted in an enhancement of mechanical and corrosion-resistant properties.

Influence of a phosphorus-based methacrylate monomer on features of thermally curable self-adhesive structural tapes

Thermally curable self-adhesive structural tapes (SATs) were prepared via UV-irradiation of a photoreactive epoxyacrylate copolymer compounded with a bisphenol-A type epoxy resin, a cationic hardener and modified with 2-hydroxyethyl methacrylate phosphate ester (G40). The influence of G40 addition on the self-adhesive features and thermal reactivity of the SATs as well as on the mechanical properties of thermally cured aluminum-SAT-aluminum overlap joints was analysed. The effect of various types of radical photoinitiators on the UV-photopolymerisation process of G40 was investigated as well. It was revealed that the addition of G40 increased adhesion of the SATs to aluminum, but it was also found that the UV-irradiation parameters (time and a UV dose applied during the SATs preparation process) were crucial for that feature. Moreover, G40 improved the shear strength of the thermally cured joints and significantly influenced epoxy groups conversion and crosslinking degree of the SATs.

Improvement of mechanical properties and anticorrosion performance of epoxy coatings by the introduction of polyaniline/graphene composite

We reported the preparation of epoxy coatings incorporated with a composite filler of poly(styrenesulfonate)-polyaniline/reduced graphene oxide (PSS-PANI/rGO) and their performance on the mechanical and anticorrosion properties. The rGO platelets were first dispersed in the PSS solution, followed by in situ oxidative polymerization of aniline. The resulting PSS-PANI/rGO composite was then blended with a bisphenol-A type epoxy at different loadings by tri-roller mill, and was subsequently cured with a curing agent. The ultimate tensile strength and tensile toughness of the epoxy composite at a loading of only 0.5 wt% PSS-PANI/rGO were improved by 39% and 127%, respectively, when compared to the respective values of the pristine epoxy. This was ascribed to their strong interfacial bonding upon curing by the reaction between the PANI and epoxy. Furthermore, the potentiodynamic polarization of the carbon steels coated with the epoxy/PSS-PANI/rGO composite revealed that the anticorrosion performance was greatly improved when compared to those with the neat epoxy and epoxy/rGO coatings. The superior anticorrosion effect was attributed to its larger tortuosity of diffusion pathways, improved interfacial strength between the epoxy and filler, and the passivation layer formed by the presence of polyaniline which was confirmed by X-ray photoelectron spectroscopy. The improved anticorrosion and toughness would allow the coatings to withstand externally mechanical impact and prevent corrosion effectively.