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Industrial crops and products have proved to be an excellent alternative to petro-based chemicals. Vegetable oils are rich in functional groups that can be transformed into monomers and polymers with applications such as biodiesel, lubricants, inks, coatings, and paints. This study describes the synthesis of rapeseed oil (RO)-based esteramide for the first time. The reaction was carried out by amidation of RO, producing diol fatty amide (N,N-bis(2-hydroxyethyl) RO fatty amide), followed by its esterification reaction with hippuric acid, resulting in RO-based hippurate amide (ROHA). Fourier-transform infrared spectroscopy and nuclear magnetic resonance confirmed the introduction of amide and ester moieties in ROHA. ROHA was further reinforced with silver nanoparticles (SNPs) to develop corrosion-protective nanocomposite coatings. ROHA/SNP coatings were scratch-resistant, impact-resistant, and flexible and showed good corrosion resistance performance toward 3.5 w/w% NaCl medium, with adequate corrosion protection efficiency, and antimicrobial behavior against Staphylococcus aureus, Chromobacterium violaceum, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. ROHA/SNP coatings can be safely used up to 250°C.

The utilization of renewable resources has increased over the last few years in different fields due to environmental and economic concerns. Cashew nut shell liquid (CNSL) is cheaper, abundantly available, and an eco-friendly agrowaste product, which holds the potential to significantly replace petro-based phenols. Present work focusses on the preparation of (i) Cardanol-based polyols (resol) in different ratios [Cardanol: formaldehyde 1:1.2([Rol.sub.1]), 1:1.6 ([Rol.sub.2]), and 1:2.0 ([Rol.sub.3])], (ii) their polyurethanes, and (iii) freestanding, transparent, flexible and thin films/coatings obtained through 'Green' route. The effect of curing temperature on the overall performance of films/coatings has also been investigated. The films/coatings obtained by baking at 80 [+ or -] 5[degrees]C (BK-[Rol.sub.1/2]PU) exhibited improved physicomechanical performance compared with films/coatings obtained at room temperature (RT-[Rol.sub.1/2]-PU). BK-[Rol.sub.1/2]-PU and RT-[Rol.sub.1/2]-PU demonstrated excellent chemical stability. XRD revealed that both BK-[Rol.sub.2]-PU and RT-[Rol.sub.1/2]-PU films were amorphous and TGA confirmed that BK-[Rol.sub.2]-PU showed higher thermal stability compared with RT-[Rol.sub.2]-PU films. The contact angle measurements indicated a higher hydrophobic character of BK-[Rol.sub.1/2]-PU (96o) relative to RT-[Rol.sub.1/2]-PU (90[degrees]). These polyurethane films/coatings can be used for protective and decorative purposes. As BK-[Rol.sub.1]/2-PU films/coatings outperformed RT-[Rol.sub.1/2]-PU, the overall results confirmed that curing temperature had a remarkable effect on the performance characteristics of coatings/films. KEYWORDS Cardanol, CNSL, films/coatings, green and sustainable material, hydrophobic polymers, polyurethane, thermal stability, 1 | INTRODUCTION The high depletion rate of non-renewable fossil reserves due to over-reliance on petro-based products, their constant usage, escalating prices, environmental and health hazards, urgently require their replacement [...]

The present manuscript describes the synthesis of urethane (ROGAU) coating material from Rapeseed oil (RO), Gallic acid (GA) and Toluylene-2,4-diisocyanate [TDI], for the first time. The reaction was accomplished in the following steps: (i) amidation of RO, producing diol fatty amide, HERA, followed by (ii) gallation reaction of HERA with GA, resulting in RO-based gallate amide (ROGA). The structural elucidation by FTIR and NMR confirmed the insertion of amide and ester moieties in the ROGA backbone. To add applicational value to ROGA, it was then derivatized by urethanation reaction with TDI to develop ambient temperature-cured ROGAU, as a corrosion protective coating material. ROGAU coatings were scratch resistant, well-adherent, and flexible to a considerable extent and showed good corrosion resistance performance toward saline medium (3.5 wt% NaCl). ROGAU coatings can be safely used up to 200°C.

Formulation of sustainable resource-based organic-inorganic hybrid protective coatings have been achieved using Linseed oil-based silica hybrid with terpolymer (TP) as basic skeletal matrix. The fabrication of TP system was performed by using systematic one pot multi-facile steps (diol fatty amide-linseed oil-based polyester amide TP) synthesis route. The conversion of ester amide functional ends of TP to urethane was initiated to enhance adhesiveness, impermeability, and corrosion resistivity of the processed hybrid material. FT-IR and NMR ([sup.1]H, [sup.13]C, and [sup.29]Si) studies help in verifying the chemical structure and progress of the reaction. The formulation of smooth corrosion resistive coating was further analyzed by transmission electron microscopy, scanning electron microscope, and electrochemical corrosion studies. The in-situ tethering and homogeneous dispersion of inorganic moiety in nanoregime throughout the TP system further enhances the stability, wettability, and corrosion protection ability of the nanohybrid vegetable oil-based coating under corrosive environment. High phase angle value at higher frequency end indicates the stability of the coating system. Such coating systems composed of sustainable resource with improved mechanical, thermal, and corrosion protective properties have great potential in future applications. KEYWORDS corrosion, nanocomposite, renewable, seed oil, terpolymer, 1 | INTRODUCTION The ever-rising pollution and corrosive environment around have been enforcing the need to use greener alternatives such as vegetable oil (VO)-derived products. [1,2] The engineered VO products [...]

This article describes the synthesis of polyesteramide (PEA) resin from Leucaena leucocephala oil (LLO) obtained from seeds of L. leucocephala tree, locally grown in King Saud University Campus. LLO was transformed into amide diol by based catalyzed amidation reaction, followed by esterification reaction with malic acid (MA), that resulted in LLO-based PEA (LPEA). The synthesis was performed without using any solvent or catalyst. Fourier-transformation infrared spectroscopy and nuclear magnetic resonance confirmed the formation of LPEA by the introduction of amide and ester moieties. LPEA was further reinforced with nano graphene oxide (GO) and fabricated into nanocomposite corrosion protective coatings (LPEA/GO). LPEA/GO coatings obtained were tough, flexibility retentive and showed good corrosion resistance performance toward 3.5 w/w% NaCl medium. Thermogravimetric analysis confirmed good thermal stability of coatings with safe usage up to 200°C.

There is an increasing demand for the development of catalytic reagents that are nontoxic due to the growing environmental concerns in the present organic transformation. Bismuth(III) compounds have significant potential as catalysts for a range of organic synthesis due to their low toxicity, strong Lewis acid catalytic activity, and great flexibility. In this research work, a series of various chemically and pharmacologically important six‐membered fused nitrogen‐/oxygen‐based heterocycle derivatives were efficiently prepared via a one‐pot multicomponent reaction starting from aromatic aldehydes, malononitrile, and barbituric acid in presence of green and reusable Lewis catalyst bismuth(III) triflate, that is, Bi(OTf)3 in EtOH/H2O (1:1) media. Bi(OTf)3 has the additional benefit of being reusable catalyst, ready availability, eco‐friendliness, and easy to handle to obtain corresponding products in excellent yields (83%–94%). Structure of all synthesized products was characterized on the basis of FT‐IR, 1H‐NMR, 13C‐NMR, and ESI–MS analysis. [ABSTRACT FROM AUTHOR]

Context: Novel optoelectronic and thermoelectric properties with broad compositional range, non-toxic nature and structural stability make halide-based double perovskites fascinating for flexible optoelectronic devices. In this work, the structural electronic, optical and transport properties of Rb2TlSbX6 (X = Cl, Br, I) were studied using density functional theory for optoelectronic devices. The elastic analysis demonstrates ductile nature, mechanical stability, anisotropic behaviour and feasibility for flexible optoelectronic devices. The band structure study using Tran–Blaha–modified Becke–Johnson (TB-mBJ) potential shows that all studied materials have direct bandgap. In addition, the bandgap of Rb2TlSbCl6 is more appropriate for optoelectronic devices. The small loss and maximum absorption in visible regions make these materials prime candidates for optoelectronic devices. The transport features indicate that all the studied double perovskites reflect p-type semiconducting behaviour as highlighted by positive Seebeck coefficient values. Furthermore, the high power factor values of Rb2TlSbX6 (X = Cl, Br, I) double perovskites make them suitable for thermoelectric device applications at high temperatures. Based on electronic optical and thermoelectric properties Rb2TlSbCl6 is the best candidate for flexible optoelectronic devices. Methods: In this paper, structural optimization of Rb2TlSbX6 (X = Cl, Br, I) double perovskites was conducted utilizing the Wien2k software based on first principle calculations with Perdew-Burke-Ernzerhof's generalized-gradient approximation (PBE-sol approximation). The TB-mBJ potential was employed to compute the accurate band gap of studied materials. The thermoelectric properties are evaluated with BoltzTraP code, showing a predominance of P-type charge carriers in all studied perovskites. This methodological strategy verifies the material's remarkable stability and optical properties and offers a solid framework for examining its potential in optoelectronic devices. [ABSTRACT FROM AUTHOR]