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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.

Polystyrene (PS)/ polyvinyl chloride (PVC) blends of different compositions, with and without organoclay (OC) were prepared by a solution casting method. PS and PVC were combined in ratios of 100/0, 90/10, 10/90, and 0/100. Local clay was treated with 0.5M NaCl to generate sodium clay (Na-clay). The Na-clay was subsequently modified using the cationic surfactant, cetylpyridinium chloride (CPC), at a concentration of 0.5 times that of Na-clay. The CPC-modified clay was denoted as organoclay (OC). The organoclay was dispersed in PS/PVC blends (90/10 and 10/90) with different weight percentages of OC (0%, 1%, 5%, and 10%). To evaluate the miscibility of PS/PVC blends, the blends with and without OC were characterized using Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM and TEM). The addition of OC to the PS/PVC blends produced exfoliated nanocomposites, as proven by XRD. The SEM and TEM micrographs showed that the PS/PVC(10/90) blend components were more miscible than those of the PS/PVC(90/10) blend, leading to favorable morphology.

Jatropha oil [JO] based poly (esteramide-urethane) coatings embedded with fumed silica nanoparticles were prepared. JO was converted to N,N-bis(2-hydroxy ethyl) JO fatty amide (HEJA) and was further modified by a tetrafunctional carboxylic acid(trans 1,2 diaminocyclo-hexane-N,N,N’,N’,-tetraacetic acid) to form poly (diamino cyclohexane esteramide) (PDCEA). PDCEA was then treated with toluene 2,4-diisocynate and fumed silica to prepare poly(diamino cyclohexane urethane esteramide) (PUDCEA) nanocomposite. The formation of PDCEA and PUDCEA nanocomposites was confirmed by FTIR, 1H &13C NMR spectroscopic techniques. The thermal behavior and morphology of PUDCEA nanocomposite coatings were investigated by TGA/DTG, DSC, SEM, EDX spectroscopy. PUDCEA nanocomposites were applied on carbon steel and their coatings were produced at room temperature. The properties of these nanocomposite coatings were investigated by standard analytical methods. The PUDCEA-3 nanocomposite showed good anticorrosion and physico-mechanical performance. These naocomposite coatings can be employed safely upto 200oC.

Vegetable oil based environmentally friendly polyurethane-TiO2 nanocomposite coatings have been synthesized by using sunflower oil derived diol, toluene diisocyanate and TiO2 nanoparticles. The chemical structure was confirmed by FTIR and NMR techniques while physico-chemical testing was carried out by standard laboratory methods. Physico-mechanical and anticorrosive tests of the coatings (in different corrosive media) have been investigated by standard methods. In addition to this the morphology and thermal stability behavior of the coatings have been carefully investigated by different techniques like XRD, TEM, TGA/DTG and DSC. The comparison of the performance of nanocomposites with the respective virgin polyurethane coatings reveals that the dispersion of nanoTiO2 enhanced the mechanical, corrosion and thermal stability behavior of the polymer. The synthesized nanocomposites can be used safely upto 250-275 °C. These sunflower oil derived polyurethane nanocomposites can be used in the world of protective coatings, as an alternative of petroleum derived corrosion protective coating materials. [ABSTRACT FROM AUTHOR]

A novel attempt has been made to incorporate azomethine group in the backbone of polyurethane ether Pongamia oil fatty amide. The overall reaction was carried out in different steps like preparation of N,N-bis(2-hydroxyethyl) Pongamia glabra oil fatty amide, poly(ether fatty amide), and poly(urethane-ether) fatty amide. The hydroxyl terminated Schiff base, ethane 1,2-di(azomethine) bisphenol, reacts with fatty amide diol and is further treated with toluylene 2,4-diisocynate (TDI) to form poly(urethane-ether azomethine) fatty amide (PUEAF). These synthesized resins were characterized by FT IR, 1H NMR, and 13C NMR spectroscopic techniques. Molecular weight of PUEAF resin was measured by gel permeation chromatography (GPC), coating was made on mild steel strips, and evaluating their physicochemical and physicomechanical analysis was carried out by standard methods. The PUEAF25 coating showed highest scratch hardness (2.5 kg), gloss (90) at 45°, pencil hardness (4H), and impact resistance (150 lb/inch). Atomic force microscopy (AFM) and differential scanning calorimetry (DSC)/thermogravimetric analysis (TGA) were used to determine the topography and thermal behavior of PUEAF. Corrosion studies of PUEAF coated mild steel were used in different corrosive media (3.5 wt% HCl, 5 wt% NaCl, and tap water) at room temperature using potentiodynamic polarization technique. The results of this study showed that PUEAF coatings exhibit good physicomechanical, anticorrosive properties and get application up to 180°C. [ABSTRACT FROM AUTHOR]

Linseed polyetheramide (LPEtA) resin was synthesized by the condensation polymerization of N-N-bis (2-hydroxyethyl) linseed oil fatty amide (HELA) with pyrogallol. The residual hydroxyl groups of LPEtA resin were further modified with isophorone diisocyanate (IPDI) to obtain linseed poly(urethane-etheramide) (ULPEtA) via addition polymerization. ULPEtA was modified with iron oxide nanoparticles in different weight percent (0.1 wt%, 0.2 wt%, 0.3 wt% and 0.4 wt%) producing ULPEtA/Fe2O3 nanocomposite. Spectroscopic characterization of HELA, LPEtA and ULPEtA was carried out by using Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H-NMR) and carbon nuclear magnetic resonance (13C-NMR) techniques. Physicochemical and physico-mechanical properties of LPEtA and ULPEtA were carried out by using standard methods. Thermal stability and anticorrosion performance were assessed by thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) and potentiodynamic polarization. The corrosion behavior of ULPEtA/Fe2O3 nanocomposite coatings on mild steel was investigated in different corrosive environments (3.5 wt% HCl, 5.0 wt% NaCl, 3.5 wt% NaOH, and tap water) at room temperature. Surface morphology study was performed through scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Coating properties such as gloss, scratch hardness, flexibility and impact resistance were evaluated using standard methods. The results of this study showed that ULPEtA/Fe2O3 nanocomposite coatings exhibit good physico-mechanical, anticorrosive properties and can be safely used up to 220°C. [ABSTRACT FROM AUTHOR]

Castor oil based polyesteramide (CPEA) resin has been successfully synthesized by the condensation polymerization of N-N-bis (2-hydroxyethyl) castor oil fatty amide (HECA) with terephthalic acid and further modified with different percentages of 7, 9, 11, and 13 wt.% of toluene-2,4-diisocyanate (TDI) to obtain poly(urethane-esteramide) (UCPEA), via addition polymerization. TiO2 (0.1, 0.2, 0.3, 0.4, and 0.5 wt%) nanoparticles were dispersed in UCPEA resin. The structural elucidation of HECA, CPEA, and UCPEA has been carried out using FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques while physicochemical and physicomechanical properties were investigated by standard methods. Thermal stability and molecular weight of UCPEA have been assessed by thermogravimetric analysis (TGA) and gel permeation chromatography (GPC), respectively. Furthermore, the corrosion behavior of UCPEA coatings on mild steel has been investigated by potentiodynamic polarization measurements in different corrosive environments (3.5 wt% HCl, 5 wt% NaCl, 3.5 wt% NaOH, and tap water) at room temperature and surface analysis by scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The antibacterial activities of the UCPEA were tested against bacteria and fungi by agar disc diffusion method. The results of this study have revealed that UCPEA nanocomposite coatings exhibit good physicomechanical, anticorrosion and antimicrobial properties, which can be safely used up to 200°C. [ABSTRACT FROM AUTHOR]

In this study, ethylene glycol polyesteramide (Eg-PEA) was synthesized fromN,N-bis (2-hydroxy ethyl) pongamia oil fatty amide and ethylene glycol tetraacetic acid (EGTA) through condensation polymerization. It was further modified by toluene 2,4-diisocynate in different wt.% (20, 25, 30, and 35) to obtain urethane-modified polyesteramide (Eg-UPEA). The synthesized resins were characterized using FT-IR,1H NMR, and13C NMR spectroscopic techniques, and molecular weight was determined by gel permeation chromatography (GPC). Physico-chemical and physico-mechanical analyses were carried out by standard laboratory methods. Thermal studies of Eg-UPEA were undertaken by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. To evaluate corrosion prevention performance Eg-UPEA-coated mild steel strips were investigated by potentiodynamic polarization in different corrosive media (5 wt.% NaCl, 3 wt.% HCL, 2.5 wt.% NaOH, and tap water) at room temperature. Thermal analysis revealed that Eg-UPEA30 may find application as an environmentally friendly corrosion protective coating and may be safely used up to 250°C. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this investigation was to develop sustainable resource-based anticorrosive coating material using Pongamia glabra seed oil and tannic acid (TA), as well as to improve the coating properties. Design/methodology/approach – TA-modified fatty amide diol was synthesized by condensation polymerization. First, Pongamia glabra seed oil was converted to fatty amide diol (Pongamia oil fatty amide, PFA) that was further modified by TA with different parts per hundred of resin (10, 15 and 20) to develop a polyether fatty amide (PFA-TA). The confirmation of reaction between TA and PFA was carried out using Fourier transform infrared spectroscopy. The thermal behavior of PFA-TA was studied by thermogravimetric analyses. Coatings of several PFA-TA resins were applied to steel (i.e. plain carbon steel) coupons to investigate their physico-mechanical and anticorrosive performance. The corrosion protection performance was observed using AC impedance and polarization tests. Findings – TA-modified fatty amide coatings showed the highest scratch hardness of 2.5 kg, flexibility (1/8 inch) and gloss at 45° was 60-62. Among all compositions, PFA-TA15 showed the best physico-mechanical and anticorrosion performance. Corrosion tests of coated panels were examined in different corrosive media (3.5 wt per cent HCl, 3.5 wt per cent NaOH and 5.0 wt per cent NaCl) using potentiodynamic polarization and AC impedance measurements. PFA-TA may find application as an eco-friendly protective coating, and thermal analyses revealed that it can be safely used up to 300°C. Originality/value – This paper provides the development of protective coatings for steel from non-edible seed oil and TA to utilize sustainable resources. [ABSTRACT FROM AUTHOR]

A novel hydrophobic Canola oil-based nanocomposite anticorrosive coating material with different contents of fumes silica (FS) was successfully synthesized via an in situ method. Firstly, a Canola oil-based hydroxyl terminated poly (oxalate-amide) was prepared by a two-step process of amidation and condensation. Secondly, the dispersion of fumed silica (1 to 3 wt.%) in hydroxyl terminated poly (oxalate-amide) was carried out, followed by reaction with toluene-2,4- diisocyanate (TDI) in order to form poly (urethane-oxalate-amide)/fumed silica nanocomposite. The structure and properties of nanocomposite were analyzed by FTIR, NMR (1H/13C), TGA/DTA, DSC, contact angle, and SEM. The physico-mechanical and electrochemical tests were performed in order to check the performance of nanocomposite coating. The results reveal that FS is homogenously dispersed in poly (urethane-oxalate-amide) matrix with a loading amount of less than 3 wt.%. The performance of nanocomposite coating improved when compared to virgin polymer. The synthesized nanocomposite coating can be used in the field of hydrophobic anticorrosive coatings. [ABSTRACT FROM AUTHOR]