Pendulum Hardness Research Articles

Diatomaceous Earth‐Containing Linseed Oil‐Based Environmentally Friendly Hydrophobic Coatings

AbstractThe use of bio‐based building blocks for the synthesis of polymers is increasing day by day. Coatings prepared by modifying bio‐based building blocks such as linseed oil (LO) and diatomaceous earth (DE) are very promising. In this study, bio‐based hydrophobic coatings were prepared by cationic photopolymerization technique using epoxidized linseed oil (ELO) and dimer diamine‐modified diatomaceous earth. The bio‐based coatings with hydrophobic properties were prepared by using the spin coating method. ELO was characterized by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H‐NMR). The thermal properties of the prepared coatings were determined by thermogravimetric analysis (TGA). The pendulum hardness, pencil hardness, and gel content of the prepared coatings were examined. Also, the hydrophobicity of the obtained bio‐based coatings was determined by contact angle measurements. The highest contact angle among the investigated compositions was found to be 110°.

Effect of graphene on properties of acrylic emulsion intumescent fire retardant coating

Nowadays, intumescent paint is one of the most popular fireproof paint products and is widely used in buildings. They can be applied to steel, wood, concrete, etc. This study aimed to enhance the properties of intumescent coating by graphene addition. The effect of graphene (GR) content on fire resistance, thermal and mechanical properties of water-based intumescent coatings were studied. Intumescent coating formulations include acrylic emulsion binder (R4152), flame retardant additives (Ammonium polyphosphate (APP) - acid source, pentaerythritol (PER) - carbon source, melamine (MEL) - foaming source), fire retardant fillers (TiO2, Al(OH)3) were prepared by mixing different graphene content (0.5, 1, 1.5 and 2 wt.% GR). The investigated coating properties were examined by fire protection test, furnace test, static water immersion test, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and mechanical properties (adhesion, pendulum hardness). The results showed that the GR could effectively enhance the fire resistance performance (from 13.6 % to 23.4 %), thermal stability (from 2.9 % to 5.2 %), water resistance (from 5.0 % to 11.9 %), and mechanical properties (from 5 % to 12 %) of the coating.

Preparation and properties of UV-curable rosin-based polyurethane coatings

Ultraviolet (UV)-curable coatings were prepared using rosin-based polyurethane as an oligomer with different active diluents and cross-linking monomers. The effects of the levels of different components on the properties of the polyurethane coatings were investigated, and the effects of the mass ratios of active diluents, cross-linking monomers, adhesion-promoting monomers and photoinitiators and curing times on the polyurethane coatings are discussed. The results showed that when hydroxypropyl acrylate was used as an end-capping agent, 40% methyl methacrylate as a reactive diluent, 10% dimethylolpropane tetracrylate as a cross-linking monomer, 7% hydroxyethyl diacrylate phosphate as an adhesion promoter, 4% 1173 as a photoinitiator and a curing time of 120 s, the UV-curable resin exhibited the best coating properties: a pendulum hardness of 0.63, a 60° gloss of 153.9, grade 2 adhesion, an impact strength of 500 J/m2 and water resistance exceeding 30 days.

Preparation of Bio-Based Polyurethane Coating from Citrullus colocynthis Seed Oil: Characterization and Corrosion Performance.

In this study, a new epoxidized oil from Citrullus colocynthis seed oil (CCSO) was obtained for a potential application in the formulation of polyurethane coatings. Initially, the fatty acid composition of CCSO was determined by gas chromatography-mass spectrometry (GC-MS). Subsequently, the epoxidation of CCSO was performed with in situ generated peracetic acid, which was formed with hydrogen peroxide (30 wt.%) and glacial acetic acid and catalyzed with sulfuric acid. The reaction was continued at a molar ratio of 1.50:1.0 of hydrogen peroxide to double bond (H2O2:DB) for 6 h at a controlled temperature of 60 °C. The resulting epoxidized oil was then used to produce a bio-based polyol by hydroxylation. The molar ratio of epoxy groups to methanol and distilled water was maintained at 1:11:2, and the reaction was carried out for 2 h at a controlled temperature of 65 °C. The major functional groups of the epoxidized oil and its polyol were validated by Fourier-transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopies. A polyurethane (PU) coating was produced from the synthesized polyol and 3HDI isocyanurate, keeping the molar ratio of NCO:OH at 1:1. The resulting PU coating was then applied to glass and aluminum panels (Al 1001). After the film was cured, the properties of the PU coating were evaluated using various techniques including pencil hardness, pendulum hardness, adhesion, gloss, chemical resistance, and EIS tests. The results show that the PU coating obtained from CCSO is a promising new raw material for coating applications.

Improving the mechanical, thermal and surface properties of polyaspartic ester bio-based polyurea coatings by incorporating silica and titania

Polyaspartic ester polyurea coatings are known for their eco-friendly properties due to the absence of VOCs and free isocyanates. While these coatings offer many advantages to the industry, achieving durability often requires the use of trimers with high NCO content. In such cases, applicators face challenges due to their notably short pot life. Furthermore, the second component used is a petroleum-based polyisocyanate, which limits its classification as a sustainable material. In this study, bio-based polyisocyanates were employed in polyaspartic coatings for the first time, thereby positioning them as sustainable alternatives without compromising their conventional properties. Fourier Transform Infrared Spectroscopy (FT-IR) and Nuclear Magnetic Resonance Spectroscopy (13C and 1H) were utilized to characterize the structure of polyaspartic ester coatings derived from biobased polyisocyanates along with solvent-free and catalyst-free PAEs. It was determined that the coating formulation had a convenient working time at room temperature. Pendulum hardness and contact angle measurements indicated that hard coatings with hydrophobicity were obtained with the addition of SiO2 and TiO2 particles without reducing the working time. The results revealed a notable 37% increase in tensile strength with the addition of 3 wt% silica compared to the base coating, and a remarkable 43 wt% increase when the coating obtained an equal proportion of titanium and silica at the same concentration. Additionally, Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) studies revealed that the composite coatings comprising titanium and silica particles exhibited higher glass transition temperatures and residual char yields compared to the base coating. The morphology and surface roughness of the coatings were characterized using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).

Phytic acid oligomers as bio-based crosslinkers for epoxy and polyol resins

AbstractIn recent years, the chemical industry is not only striving to produce the best possible products for various applications, but the new products should ideally be based on renewable resources. The ideal case of "cradle to cradle" is generally not achievable in the coatings industry, as maximizing product life and preventing product degradation in the environment is usually one of the main goals of the coatings industry. Therefore, if the coatings industry wants to act sustainably, its efforts should be focused on renewable raw materials. This paper presents a process that makes the renewable raw material phytic acid easily accessible for conventional epoxy and polyol resin coating systems through hydrophobization- and oligomerization. Phytic acid, as a phosphorus reservoir in plants and with beneficial properties for corrosion protection and as a flame retardant, could be a new base for various coatings. In this work, a simple one-pot oligomerization of phytic acid with green mono- and difunctional alcohols is investigated. The aim of this work is to create a phytic acid hardener system based on renewable raw materials that can produce coatings with solvent-based epoxy and polyol binders as well as water-based epoxy binders. The successful reaction was observed by infrared, 1H-NMR, and 31P-NMR spectroscopy and the acid equivalent weight was determined by conductivity titration. The renewable curing agent was then used equivalently with different binder systems to prepare coatings. Crosslinking and glass transition temperature were monitored using oscillatory rheology. The coatings were applied to glass plates and the pendulum hardness was measured. A simple heating test followed by 31P-NMR and IR spectroscopy was also performed to demonstrate the stability of phytic acid under reaction conditions.

Preparation of a water‐absorbent mesoporous material and film to simulate the infrared spectrum of plants

AbstractHyperspectral imaging poses great challenges to traditional camouflage materials, primarily because there is a huge difference between the reflectance spectra of camouflage materials and natural plants in the 1400–2000 nm band. The difficulty of simulating the natural plant spectrum lies in reproducing the absorption peak of water by increasing the water content in a camouflage material. Herein, a mesoporous (MS) material is used to simulate the plant spectrum because such material can absorb and retain a large amount of water. MS was prepared via a two‐step method using tetraethyl orthosilicate and tetrabutyl titanate. The characteristics of the as‐prepared MS were examined via X‐ray diffraction, transmission electron microscopy, ultraviolet–visible diffusion reflectance spectroscopy and nitrogen adsorption–desorption isotherms. In addition, a film was prepared using the fully absorbent mesoporous material, and the water content was determined via near‐infrared spectroscopy and thermogravimetric analysis. The bonding between the mesoporous material and resin was examined via field emission gun scanning electron microscopy. The mechanical properties of the film were measured by a pendulum hardness tester and a cylindrical bending tester. The results indicate that low‐temperature synthesis followed by high‐temperature hydrothermal treatment is conducive to expanding the mesopore aperture, reaching a maximum of 23 nm. Moreover, the regular structure of the as‐prepared titanium‐containing mesoporous material is maintained under high hydrothermal temperature. The mesoporous film exhibits a good water absorption capacity of up to 80% by mass and can effectively simulate the spectrum of plants. The mechanical properties of the film are good, and the hardness of the film is related to the content of mesoporous powder. © 2023 Society of Industrial Chemistry.

Adhesion strength and pendulum hardness of some coatings in wood heat-treated by different methods

Beech (Fagus sylvatica L.) and pine (Pinus sylvestris L.) wood specimens were heat-treated separately at three different temperatures (170 °C, 190 °C, and 210 °C) with steam treatment method (STM), oil treatment method (OTM), and hot-air treatment method (HTM). Then, the specimen surfaces were coated with water-based, polyurethane-based, and oil-based varnishes according to industrial applications. The study results show that both hardness and adhesion strength values of STM and HTM treated specimens were similar for both wood species. In contrast, these values were generally lower in OTM-treated specimens. For all applied methods, heat treatment temperature had no significant effect on hardness values. Varnish adhesion strength decreased in all heat-treated wood specimens compared to untreated specimens. Adhesion strength also decreased in STM- and HTM-treated specimens with increasing heat treatment temperature. Hardness values increased in all specimens coated with polyurethane- and water-based varnish compared to the specimens without varnish. However, hardness decreased in the specimens coated with oil-based varnish. In contrast, the highest adhesion resistance was determined in the specimens coated with oil-based varnish under all heat treatment conditions. In addition, the heat treatment method is more effective relative to the hardness values and the treatment temperature is more effective relative to the adhesion strength of varnished pine and beech specimens.

Fire-retardant acrylic coating by silica -coated limestone (SCL) microencapsulation

ABSTRACT Silica-coated limestone (SCL) microcapsule was synthesized and successfully introduced into acrylic resin to produce fire-retardant coatings. SCL microcapsules were prepared by encapsulating limestone granules with silica nanoparticles using epoxy resin as a binder. The morphology and the chemical composition of the SCL microcapsules were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), respectively. The performance of SCL microcapsules on mechanical, flame retardant and thermal stability of the coatings was thoroughly investigated using FTIR, SEM, thermogravimetric analysis (TG), smoke density test, adhesion pull-off test, pendulum damping test and cone calorimeter test. The results shows that while the adhesion strength, pendulum hardness and limiting oxygen index (LOI) increased remarkably, the values of flame spread ratings (FSR), specific optical density (ODs), heat release rate (HRR), total heat release rate(THRR), smoke production rate (SPR) and total smoke production rate (SPR) decreased significantly with the introduction of SCL microcapsules. The TGA results confirm that incorporation of SCL microcapsules increases the thermal stability and boosts formation of large char layers.

Chemically-resistant epoxy novolac coatings: Effects of size-fractionated technical Kraft lignin particles as a structure-reinforcing component

To provide protection against corrosion in harsh environments, high performance anticorrosive coatings are applied on steel structures at all scales. However, to also limit the use of fossil-based ingredients, there is a growing demand to incorporate renewable raw materials in the coating formulations.In this study, to replace pigments and fillers of an epoxy novolac coating, technical Kraft lignin particles were ground and size fractionated (i.e., sieved), and used for formulation work. The effects of sieved and unsieved Kraft lignin, as structure-reinforcing components, on the anticorrosive and mechanical performance of epoxy coatings were subsequently investigated using the following methods: size exclusion chromatography (SEC), phosphorous nuclear magnetic resonance spectroscopy (31P NMR), scanning electron microscopy (SEM), differential scanning calorimeter (DSC), salt spray exposure, pull-off, König pendulum hardness, and chemical resistance tests.Compared to the unsieved-lignin reference (U-L EN), the coating based on lignin fines (S-L EN) showed about 31 % lower rust creep after 70 days of salt spray exposure. However, no surface defects or chemical degradation were observed for any of the coatings.For the S-L EN coating, excellent adhesion strength (23 MPa) and impact resistance (0.49 N), relative to reference values of 17 and 13 MPa and 0.41 and 0.07 N for commercial and lignin-based diglycidyl ether bisphenol F (L-DGEBF) coatings, respectively, were measured.The addition of lignin particles did not influence the chemical resistance, the hardness, and the glass transition temperature of the epoxy novolac coatings.In summary, chemically unmodified Kraft lignin particles, after grinding and sieving, can be incorporated in epoxy novolac coatings (up to 25 vol%), thereby providing a bio-based alternative to pigments and fillers in heavy duty coatings (primers in particular).

Effects of artificial weathering on some surface properties of Anatolian chestnut (Castanea sativa Mill.) wood applied with yacht varnish

Anatolian chestnut wood is an industrial material used in various indoor and outdoor applications in Turkey. This study investigated the effects of artificial weathering (times: 144, 288, 432, and 576 h) conditions on color parameters (L*, ∆L*, a*, ∆a*, b*, ∆b*, ∆E*, ho, ∆H*, C*, and ∆C*), glossiness values at 60° in different directions (║ and ⊥), pendulum hardness (König method) values, and surface adhesion strength (pull-off method, MPa) on the layers of yacht varnishes applied to Anatolian chestnut (Castanea sativa Mill.) wood. The results showed that the univariate analysis of variance was significant by obtaining the weathering factor for all tests. While the brightness values perpendicular (⊥) and parallel (║) to the fibers increased at 144 and 288 h, they decreased at 432 and 576 h. Adhesion strength to the surface decreased 4.35% at the 576th h of weathering. At the end of weathering, a*, C*, b*, and pendulum hardness values increased, while ho and L* values decreased compared to un-weathered samples. The ∆a* and ∆E* values increased with increased weathering time.

Isıl işlem sonrası poliüretan vernik uygulanmış kestane odununda salınımsal sertlik üzerine yapay yaşlandırmanın etkileri

The effects of artificial weathering (576 h) on the pendulum hardness values of Anatolian chestnut (Castanea sativa Mill.) wood applied with polyurethane varnish (PU) after heat treatment at 190℃ for 1.5 h and at 212℃ for 2 h were investigated. The results revealed that heat treatment, weathering period, and interaction were significant. The hardness values of the heat-treated materials were higher than those of the non-heat-treated test samples. The highest hardness value was determined in the un-weathered group of the test samples that were heat-treated at 190°C for 1.5 h while the lowest value was determined in the group that was heat-treated at 190°C for 1.5 h and weathered for 432 h. The highest reduction rates after weathering were obtained on samples that were heat-treated at 190℃ for 1.5 h, followed by heat-treated at 212℃ for 2 h and non-heat-treated. It was observed that the heat treatment application caused different pendulum hardness values in chestnut wood samples covered with polyurethane varnish.

Thiol-ene photopolymerization meets azide-alkyne click reactions: P/N/Si-containing, dual curable eugenol-based hybrid coatings

The use of bio-based building blocks for the synthesis of polymers is increasing day by day. Among the bio-based building blocks, eugenol is a highly promising monomer for the preparation of thermoset materials. In this study, we combined thiol-ene photopolymerization (TEP) and thermal azide-alkyne cycloaddition click reactions to prepare eugenol-based thermally stable, P-, N-, and Si-containing networks. To this end, we synthesized a P-containing, eugenol-based monomer bearing azide group and a siloxane compound containing an alkyne group. By mixing these monomers with multifunctional thiols and by utilizing a dual-curing strategy, we managed to obtain optically transparent and thermally stable coatings with excellent adhesion to glass substrates. Thermal stability, optical transmittance, pendulum hardness, solvent resistance, and the adhesion performance of the coatings were evaluated. The gel contents of the thermoset materials were found to be over 95%. At 600 °C, the char yields of the dual-cured coatings were found to be over 30%. Coatings were also found to be resistant to acidic and basic conditions as well as solvents.

Influence of bio-based 2,5-furandicarboxylic acid on the properties of water-borne polyurethane dispersions

Two sets of polyesters derived from 1,6-hexanediol, succinic acid, and varying amounts of a second aromatic dicarboxylic acid have been prepared. In the first set, isophthalic acid has been used as an established rigid building block for these types of materials. In the second set, isophthalic acid was replaced by the bio-based aromatic diacid 2,5-furandicarboxylic acid. The structure and properties of the polyesters have been characterized. All polyesters prepared were subsequently used as polyols for the synthesis of water-borne polyurethane dispersions. Films were prepared from the aqueous dispersions to characterize the performance of the materials. It was observed that the bio-based 2,5-furandicarboxylic acid not only has similar beneficial effects on the thermal and mechanical properties of the polyurethane coatings, but in some cases, like pendulum hardness, tensile strength and glass transition temperature, it was even able to surpasses the properties of its fossil-based counterpart.

Improving the performance of biobased polyurethane dispersion by the incorporation of photo-crosslinkable coumarin

High biobased carbon content polyurethane dispersions (PUD) are a more sustainable alternative to conventional oil-derived waterborne dispersions in coatings. However, there are still many performance limitations from restricted availability of effective renewable monomers and oligomers. This work demonstrates the improvement of the properties of high biobased content PUD and derived coating by introducing a photo-reversibly crosslinkable coumarin as chain extender within the structure. The effect of partial substitution of 1,3-propanediol biobased by a di-hydroxy photo-reactive cyclic coumarin on the particle size and the stability was analyzed by dynamic light scattering (DLS) and multiple light scattering (MLS). The lateral and more rigid structure of coumarin involved a moderated increment in particle size without significant effect on the dispersion stability for at least 45 days. Associated improvement in hardness and toughness was also demonstrated by tensile test, pendulum hardness, pencil hardness and scratch resistance test. Furthermore, controlled UV irradiation of the polyurethane gave rise to a mechanical performance adjustment from reversible photo-crosslinking and scission of the coumarin molecules within the macromolecular structure. A 70% dimerization degree of the coumarin within the polyurethane film by UV light provided a partially reversible threefold higher tensile strength than that of the original biobased formulation as an effective tool to tune the response of biobased polyurethanes.Graphical

Corrosion Resistance Performance of Epoxy Coatings Incorporated with Unmilled Micro Aluminium Pigments

The current work is in continuation of our previous work where we reported changes in the properties of epoxy coatings using two different types of hardener in different stoichiometric ratios. The best results-oriented coating stoichiometry was then taken in this research for further modification with the incorporation of 1, 2 and 3 wt.% micro aluminium (Al) pigments designed for coating carbon steel panels. After 7 d of curing, the coated panels were characterized using X-ray diffraction (XRD), (SEM) scanning electron microscopy, (TGA) thermogravimetric analysis, pendulum hardness, a scratch test and nano-indentation. Electrochemical tests were carried out for various exposure periods of time, i.e., 1 h, 7 d, 14 d, 21 d and 30 d, in a 3.5% sodium chloride (NaCl) solution. For the coatings, we found that the presence of 1% Al provided the highest corrosion resistance after exposure periods in the NaCl solution. We also found that prolonging the immersion time decreases the corrosion resistance after 7 d, but increasing the time of immersion to longer periods (14 d, 21 d and 30 d) enhances the corrosion resistance and reduces the degradation of the coatings.

Characterisation and adhesion properties of UV-cured natural rubber-based adhesives

The adhesion properties of rubber adhesives based on SMR-L, ENR-25 and ENR-50 elastomers cured by ultraviolet (UV) light radiation were examined. Various parameters were studied, namely the effects of UV radiation dosages and coating thickness on adhesion properties such as tackiness, peel strength, and shear resistance. Prior to curing, the viscosity of uncured adhesives was analysed in order to understand the effect of adding benzoyl peroxide cross-linker. The reduction of double bonds due to UV-curing was confirmed by FTIR analysis. These adhesives were properly cured after 15 passes (repetitive irradiation on moving conveyor belt) inside UV-curing machine, as proven by both pendulum hardness and gel content tests. Results indicated that for all rubber-based adhesives, 120 μm coated samples showed higher peel strengths than their 60 μm counterparts. ENR-25 based adhesives showed better peel strength as compared to the others, while SMR-L based adhesives possessed higher tackiness and shear resistance than those of ENR-25 and ENR-50 based adhesives.

Improvement of Mechanical Properties and Solvent Resistance of Polyurethane Coating by Chemical Grafting of Graphene Oxide.

Waterborne polyurethane coatings (WPU) are widely used in various types of coatings due to their environmental friendliness, rich gloss, and strong adhesion. However, their inferior mechanical properties and solvent resistance limit their application on the surface of wood products. In this study, graphene oxide (GO) with nanoscale size, large surface area, and abundant functional groups was incorporated into WPU by chemical grafting to improve the dispersion of GO in WPU, resulting in excellent mechanical properties and solvent resistance of WPU coatings. GO with abundant oxygen-containing functional groups and nanoscale size was prepared, and maintained good compatibility with WPU. When the GO concentration was 0.7 wt%, the tensile strength of GO-modified WPU coating film increased by 64.89%, and the abrasion resistance and pendulum hardness increased by 28.19% and 15.87%, respectively. In addition, GO also improved the solvent resistance of WPU coatings. The chemical grafting strategy employed in this study provides a feasible way to improve the dispersion of GO in WPU and provides a useful reference for the modification of waterborne wood coatings.

Enhancing the Mechanical Properties of Waterborne Polyurethane Paint by Graphene Oxide for Wood Products.

Water-based polyurethane paint is widely used for wood furniture by virtue of the eco-friendliness, rich gloss, and flexible tailorability of its mechanical properties. However, its low solution (water or alcohol) resistance and poor hardness and wear resistance limit its application. The emerging graphene oxide has a high specific surface area and abundant functional groups with excellent mechanical properties, endowing it with great potential to modify waterborne polyurethane as a nanofiller. In this study, graphene oxide prepared by Hummers' method is introduced in the chemosynthetic waterborne polyurethane through physical blending. The testing results demonstrate that the appropriate usage of graphene oxide at 0.1 wt% could obviously improve water absorption resistance and alcohol resistance, significantly enhancing the mechanical properties of waterborne polyurethane paint. The corresponding tensile strength, abrasion resistance, and pendulum hardness of the graphene oxide-modified paint film increase by 62.23%, 14.76%, and 12.7%, respectively, compared with the pristine paint film. Meanwhile, the composite paint film containing graphene oxide possesses superiority, including gloss, abrasion resistance, pendulum hardness, and tensile strength in contrast with the commercial paint. The use of graphene oxide to enhance the waterborne polyurethane possesses strong operability and practical value, and could provide useful reference for the modification of waterborne wood paint.

Influence of graphite particles in UV-curable corrosion protection coating from palm oil based urethane acrylate (POBUA)

Replacing petroleum oil with renewable sources from natural oil in producing polymer coating is being widely attracting many researchers and inventors. In this study, palm oil-based urethane acrylate (POBUA) coating was developed as a protective coating for mild steel by using the ultraviolet irradiation technique. The POBUA was synthesized by reacting acrylated palm oil and isocyanate via in situ intercalative polymerizations with the presence of hydroxyethyl acrylate and 4 methoxy phenol (4mph). Different loadings of graphite particles (0.1 wt%, 0.5 wt% and 0.8 wt%) were introduced into the POBUA with the presence of Irgacure 184 as the photoinitiator. The formulated coating resin was applied on the mild steel substrates and the overall performances were investigated using Fourier transform infrared spectroscopy , contact angle measurements, X-Ray Diffraction, thermogravimetric analysis, electrochemical impedance spectroscopy , and Field Emission Scanning Electron Microscopy . Meanwhile, Gel content extraction and Pendulum Hardness were done on the cured film to investigate the performance of the polymerized coating polymer. The obtained results exposed good distribution of graphite particles in the POBUA polymeric matrix will influence the overall performance of the POBUA coatings at POBUA + 0.5 wt% graphite. Infrared spectrum demonstrated the formation of the crosslinked network was not disrupted with the addition of graphite particles, while increment of crystallinity index and hardness observed. Meanwhile TAFEL polarization elucidate the present of graphite particles reduced the curable POBUA coating corrosion current density from 102.6 × 10 −6 to 27.3 × 10 −12 Acm −2 with decreasing of mild steel corrosion rate per year from 31.24mpy to 125.1 × 10 −6 mpy. However, morphology showed that the addition of high graphite content (0.8 wt%) increased the tendency to particles agglomeration. Nevertheless, the results obtained showed that the presence of graphite particles in POBUA is beneficial in improving the strength of the coating against surface degradation and corrosion. This research demonstrates that POBUA/Graphite curable coating has a good potential application in mild steel protection. • Anticorrosion study for palm oil-based urethane acrylate enhanced by graphite was carried out. • Graphite particles influences the corrosion behavior as shown in Tafel plot. • The strength of the coating against corrosion was enhanced with the presence of graphite. • Graphite particles enhanced charge transfer resistance R ct of POBUA. • The POBUA R ct increased from 0.92 × 10 6 Ω up to 9.253 × 10 6 Ω.