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Vegetable oil has been extensively investigated as a precursor to the eco-friendly coating as an alternative to petrochemical-based resources due to its lower carbon footprint properties. In view of this, jatropha oil (JO), a type of non-edible oil, has received significant attention in this field. The present study was undertaken to utilize acrylated epoxidized jatropha oil (AEJO) resin and to evaluate the anti-corrosion performance with the addition of graphene nanoplatelets (GNP). AEJO-GNP nanocomposites coatings were obtained after three passes of ultraviolet (UV) irradiation. The corrosion protection of all nanocomposites coatings was investigated by electrochemical measurements. The results showed that the corrosion performance of AEJO-GNP nanocomposites coatings improved from the blank coating. Among all coatings tested, AEJO-0.5 wt% GNP exhibited the strongest barrier property and maximum performance in corrosion protection. The result was supported by water contact angle and pull-off adhesion tests. In addition, the highest pull-off adhesion strength for GNP fillers added coatings was established at 0.5 wt% of GNP. High hydrophobicity and pull-off adhesion strength coatings provided a physical barrier that created a tortuosity pathway for corrosive electrolytes to reach the metal surface and thus showed better anti-corrosion resistance. Thus, nanocomposites coatings with 0.5 wt% GNP exhibited the best anti-corrosive efficacy and surface coating property.

Recently, the antibacterial properties of Carvacrol (Carv) have been significantly reported. However, due to the unstable properties of Carv under various environment conditions, research approaches tailored towards its widespread and efficient use in various antimicrobial applications are scarce. Here, we discuss progress towards overcoming this challenge by utilising the encapsulation of Carv in gellan gum hydrogels to form thin films (GG-Carv) containing different concentrations of Carv (0.01–0.32 M). FTIR spectrum of GG-Carv revealed that both functional groups from GG and Carv existed. The carbon, hydrogen and nitrogen elemental analysis further supported the encapsulation of Carv with the changes in the element percentage of GG-Carv. Both swelling and degradation percentage increased with time and the decreasing patterns were observed as the concentration of Carv increased. In an antibacterial study, GG-Carv exhibited significant antibacterial activity against E. coli with the clear inhibition zone of 200 mm and the detection of bacterial growth showed enhancement with continuous decline throughout the study as compared to free-standing Carv.

With the continuing efforts to explore alternatives to petrochemical-based polymers and the escalating demand to minimize environmental impact, bio-based polymers have gained a massive amount of attention over the last few decades. The potential uses of these bio-based polymers are varied, from household goods to high end and advanced applications. To some extent, they can solve the depletion and sustainability issues of conventional polymers. As such, this article reviews the trends and developments of bio-based polymers for the preparation of polymer electrolytes that are intended for use in electrochemical device applications. A range of bio-based polymers are presented by focusing on the source, the general method of preparation, and the properties of the polymer electrolyte system, specifically with reference to the ionic conductivity. Some major applications of bio-based polymer electrolytes are discussed. This review examines the past studies and future prospects of these materials in the polymer electrolyte field.

Biobased polymers are useful materials in substituting conventional petroleum-derived polymers because of their good properties, ready availability, and abundance in nature. This study reports a new jatropha oil-based gel polymer electrolyte (GPE) for use in dye-sensitized solar cells (DSSCs). The GPE was prepared by mixing jatropha oil-based polyurethane acrylate (PUA) with different concentrations of lithium iodide (LiI). The GPE was characterized by infrared spectroscopy, thermal analysis, lithium nuclear magnetic resonance analysis, electrochemical analysis, and photocurrent conversion efficiency. The highest room-temperature ionic conductivity of 1.88 × 10–4 S cm–1 was obtained at 20 wt % of LiI salt. Additionally, the temperature-dependent ionic conductivity of the GPE exhibited Arrhenius behavior with an activation energy of 0.42 eV and a pre-exponential factor of 1.56 × 103 S cm–1. The electrochemical stability study showed that the PUA GPE was stable up to 2.35 V. The thermal stability of the gel electrolyte showed an improvement after the addition of the salt, suggesting a strong intermolecular interaction between PUA and Li, which leads to polymer–salt complexation, as proven by Fourier transform infrared spectroscopy analysis. A DSSC has been assembled using the optimum ionic conductivity gel electrolyte which indicated 1.2% efficiency under 1 sun condition. Thus, the jatropha oil-based GPE demonstrated favorable properties that make it a promising alternative to petroleum-derived polymer electrolytes in DSSCs.

Currently, there is a growing trend of using bio-based materials from renewable resources in the construction of polymer electrolytes. In this study, a gel polymer electrolyte from Jatropha oil-based polyurethane acrylate (PUA) was prepared by doping the PUA with various concentrations (0–30 weight%) of potassium iodide (KI) salt. The PUA gel electrolyte was characterized by Fourier-transform infrared spectrometry (FTIR), thermal analysis and electrochemical analysis was performed by using electrochemical impedance spectroscopy. Subsequently, the dielectric properties of the gel polymer electrolyte were studied. A conductivity of 1.59 × 10−4 S cm−1 was achieved for the PUA incorporated with 25 weight% KI at room temperature. The dielectric study indicated the non-Debye nature of the materials. It has been shown, via transference number measurement that the conducting species in this work were predominantly ions, with only 4% contribution from electrons. An electrochemical stability window of 2.0 V was obtained by using linear sweep voltammetry for the highest conducting gel electrolyte.

Epoxidized jatropha oil (EJO) was investigated as a sustainable alternative to petrochemical-based plasticizers to reinforce the plastics, leading to increased ductility and toughness of kenaf-reinforced poly(lactic acid) (PLA). The EJO was melt-blended into kenaf-reinforced PLA at concentrations from 1 wt% to 5 wt%. The blends were then hot-pressed into sheets to characterize their mechanical and physical properties. Kenaf fibers were treated with 6% sodium hydroxide (NaOH), and the effects thereof on the composites’ tensile, flexural, and impact properties, as well as their water absorption and density were stu died. The impact strengths of the kenaf-reinforced PLA composites were improved with the addition of EJO up to 5 wt%, with a maximum over 10 times that of the neat PLA. The flexural strength and modulus increased 4% and 50%, respectively, for treated kenaf-reinforced PLA plasticized with EJO. This increase demonstrated the alkalization treatment’s notable improvements to the composites’ properties. Furthermore, analysis by scanning electron microscopy (SEM) of the composites’ tensile fracture surfaces indicated better interaction adhesion of the treated kenaf-reinforced PLA plasticized with EJO compared with the untreated composites. Compared to untreated 1 wt% EJO biocomposites, the treated 5 wt% EJO biocomposites reduced water absorption from 3.1% to 1.6% after 8 weeks of immersion.

Polyurethane acrylate (PUA) from vegetable oil has been synthesized and prepared for solid polymer electrolyte. Polyol has been end-capped with Toluene 2,4-Diisocyanate (TDI) followed by hydroxylethylmethylacrylate (HEMA) in a urethanation process to produce PUA. The mixtures were cured to make thin polymeric films under UV radiation to produce excellent cured films which exhibit good thermal stability and obtain high ionic conductivity value. 3 to 15 wt. % of ethylene carbonate (EC) mixed with 25 wt. % LiClO4 was added to PUA to obtain PUA electrolyte systems. PUA modified with plasticizer EC 9 wt. % achieved the highest conductivity of 7.86 × 10−4 S/cm, and relatively improved the linear sweep voltammetry, transference number and dielectric properties. Fourier Transform Infrared Spectroscopy (FTIR) and dielectric analysis were presented. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), followed by X-ray Diffraction (XRD) and morphology have been studied. The addition of plasticizer to the polyurethane acrylate shows significant improvement in terms of the conductivity and performance of the polymer electrolyte.

A low cost, abundant, and renewable vegetable oil source has been gaining increasing attention due to its potential to be chemically modified to polyol and thence to become an alternative replacement for the petroleum-based polyol in polyurethane production. In this study, jatropha oil-based polyol (JOL) was synthesised from non-edible jatropha oil by a two steps process, namely epoxidation and oxirane ring opening. In the first step, the effect of the reaction temperature, the molar ratio of the oil double bond to formic acid, and the reaction time on the oxirane oxygen content (OOC) of the epoxidised jatropha oil (EJO) were investigated. It was found that 4.3% OOC could be achieved with a molar ratio of 1:0.6, a reaction temperature of 60 °C, and 4 h of reaction. Consequently, a series of polyols with hydroxyl numbers in the range of 138-217 mgKOH/g were produced by oxirane ring opening of EJOs, and the physicochemical and rheological properties were studied. Both the EJOs and the JOLs are liquid and have a number average molecular weight (Mn) in the range of 834 to 1457 g/mol and 1349 to 2129 g/mol, respectively. The JOLs exhibited Newtonian behaviour, with a low viscosity of 430-970 mPas. Finally, the JOL with a hydroxyl number of 161 mgKOH/g was further used to synthesise aqueous polyurethane dispersion, and the urethane formation was successfully monitored by Fourier Transform Infrared (FTIR).

A green nanocomposite film from cellulose nanowhiskers (CNWs) and Jatropha oil-based polyurethane (JOPU) was prepared. A commercial grade of microcrystalline cellulose derived from wood pulp was purchased and isolated to CNW via acid hydrolysis using 65% (w/w) sulfuric acid. JOPU was produced using in-house synthesis of Jatropha-oil polyol and 4,4′-diphenyl-methane diisocyanate (MDI). Dimethylformamide (DMF) was used as a polar organic solvent to disperse CNWs incorporated with JOPU at different ratios. Green nanocomposite films were prepared by casting in Teflon petri dish and thermal curing of the stable suspensions under vacuum conditions. Both CNW and composite films were characterized. The morphology of CNW was examined by using transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). Chemical structures of JOPU and JOPU/CNW films were analyzed using Fourier transform infrared spectroscopy (FTIR). Thermal stability tests of the films were carried out using thermogravimetric analysis (TGA). Mechanical properties, such as tensile strength, Young modulus, and elongation at break, were investigated. Other properties such as density and water uptake were also determined. It can be concluded that composite films made from JOPU with CNW as filler showed an improved performance over JOPU films.

The non-edible seed oil of the Jatropha plant is a renewable and sustainable material to produce vegetable oil-based epoxy and epoxy acrylate as raw polymeric material. The objective of this study is to synthesis Jatropha seed oil-based epoxy and acrylate epoxy resins through conventional methods. An epoxy ring of Epoxidised Jatropha Oil (EJO) was formed through an in-situ epoxidation process using hydrogen peroxide and formic acid as an oxygen donor and oxygen carrier respectively. Acrylated Epoxidised Jatropha Oil (AEJO) was produced by reacting EJO with acrylic acid with the existence of triethylamine and 4-methoxyphenol as a catalyst and inhibitor respectively. The measured oxirane-oxygen content (OOC) of EJO was 4.99%. The acid value of the AEJO was determined at 4.42 mg KOH/g. Both the EJO and AEJO were characterised by FTIR and 1H NMR spectroscopies.

Cellulose I can be irreversible transformed into cellulose II via mercerisation or regeneration treatments. In the past few decades, mercerisation was used mainly to improve fibre properties for textile industries. A few studies have focused on the effects of mercerisation treatment on the cellulose polymorph itself and after it was downscaled to nanosize. This study aims to characterise the micro size crystalline cellulose after complete polymorph conversion via mercerisation technique and investigate its effects on isolation to nanosize crystalline cellulose. A microcrystalline cellulose (MCC) was purchased and converted into cellulose II via mercerisation technique. Sulphuric acid hydrolysis was carried-out to produce nanocrystalline cellulose (NCC). The MCC and NCC of different polymorphs were then characterised and analysed for its crystallography, morphology, particles size distribution and thermal stability using wide-angle X-ray diffraction (WXRD), electron microscopes, dynamic light scattering analyser and thermogravimetric analyser, respectively. Both MCC and NCC fibres showed complete conversion of cellulose I to cellulose II and decrement of crystallinity index (CI). Electron micrographs revealed that both cellulose II polymorph fibres (MCC II and NCC II) were morphological affected. The analysis of size distribution and dimension measurement confirmed that mercerisation treatment causing increment in fibre diameter and shortened length. The thermal stability of both cellulose II polymorph fibres (MCC II and NCC II) was also found to be improved.