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Highlights: [•] Conducting polymer composite coatings. [•] Superior protection in aggressive environments. [•] Cost effective and eco-friendly. [•] Protection through barrier mechanism. [•] Improved lifetime and serviceability. [Copyright &y& Elsevier]

Purpose – Polymeric systems based on polyesteramides (PEA) are high performance materials, which combine the useful properties of polyester and polyamide resins, and find many applications, most importantly as protective surface coatings. The purpose of this paper is to characterise and evaluate new modified anti-corrosive PEA resins for use in protective coating formulations. Design/methodology/approach – In the study report here, new modified PEA compositions were prepared and evaluated as vehicles for surface coating. The PEA resins were obtained by means of a condensation polymerisation reaction between phthalic anhydride (PA) and N,N-bis-(2-hydroxyethyl) linseed oil fatty acid amide (HELA) as the ingredient source of the polyol used. The phthalic anhydride was partially replaced with N-phthaloylglutamic acid NPGA as the ingredient source of the dibasic acid. The structure of the resin was confirmed by FT-IR spectral studies. Coatings of 50±5 μm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. The coating performance of the resins was evaluated using international standard test methods and involved the measurement of phyisco-mechanical properties and chemical resistance. Findings – The tests carried out revealed that the modified PEA based on N-phthaloylglutamic acid (NPGA) enhanced both phyisco-mechanical and chemical properties. Also, the resins were incorporated within primer formulations and evaluated as anti-corrosive single coatings. The results illustrate that the introduction of N-phthaloylglutamic acid, within the resin structure, improved the film performance and enhances the corrosion resistance performance of PEA resins. Practical implications – The modified PEA compounds can be used as binder in paint formulations to improve chemical, physical and corrosion resistance properties. Originality/value – Modified PEA resins are cheaper and can be used to replace other more expensive binders. These modified PEA resins can compensate successfully for the presence of many the anticorrosive paint formulations and thus lower the costs. The main advantage of these binders is that they combine the properties of both polyester and polyamide resins based on nitrogenous compound, are of lower cost, and they also overcome the disadvantages of both its counterparts. Also, they can be applied in other industrial applications. [ABSTRACT FROM AUTHOR]

Abstract: In this paper new modified anti-corrosive polyesteramide resins were obtained by means of a condensation polymerization reaction between N,N-bis (2-hydroxyethyl) linseed oil fatty acid amide (HELA) and phthalic anhydride (PA), which was partially replaced with pyromellitimide acetic acid (PAA) as a new dibasic acid source. The structure of the resin was confirmed by FT-IR and 1H NMR spectral studies. The coatings of 50±5μm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. The coating performance of the resins was evaluated using international standard test methods and involved the measurement of phyisco-mechanical properties such as viscosity, drying time, specular gloss, pencil hardness, adhesion, flexibility and impact resistance. Chemical resistance of the resins to water, acid, alkali and solvent was also evaluated to ascertain their suitability as a surface coatings vehicle. The results show that the modification enhances both phyisco-mechanical and chemical properties. The resins were incorporated within primer formulations and evaluated as anti-corrosive single coatings. The results illustrate that the introduction of pyromellitimide acetic acid, containing a pyromellitimide ring, within the resin structure, enhances the corrosion resistance performance of polyesteramide resins. [Copyright &y& Elsevier]

The resourceful employment of vegetable oil based polymers in coating applications that yield novel properties, faces challenges usually in their processing. We have developed polyesteramide coatings from linseed ( Linnum ussitatissium seeds) oil with improved coating properties. Linseed oil was first converted into N, N-bis 2-hydroxy ethyl linseed oil fatty amide diol (HELA). The resin was synthesized by the reaction of HELA with ethylenediaminetetraacetic acid (EDTA) to develop ethylenediamine polyesteramide (Ed-PEA). The latter was further treated with poly (styrene co-maleic anhydride) (SMA) in different (35-50) phr (part per hundred part of resin) to obtain ambient cured polyesteramide (AC-PEA). The structural elucidation of polymeric resin (AC-PEA) was carried out by FT-IR, H-NMR, and C-NMR spectroscopic techniques. Thermal behavior of AC-PEA was studied by thermogravimetric analyses (TGA) and differential scanning calorimetry (DSC). The coatings of AC-PEA were prepared on mild steel strips to investigate their physico-mechanical and anticorrosive behavior (in acid, alkali, water and xylene). It was found that among all the samples, the one having 45 phr of SMA showed the best physico-mechanical and corrosion resistance performance. The thermal stability performance suggests that AC-PEA45 system could be safely used up to 150 °C. [ABSTRACT FROM AUTHOR]

A novel attempt has been made to develop the room temperature cured polyesteramide resin by condensation polymerization reaction between fatty amide diol ( N, N-bis 2-hydroxy ethyl linseed oil fatty amide) obtained from oil of linseed ( Linum ussitatissimum seeds) and pyridine dicarboxylic acid (PyA) to develop pyridine polyesteramide (Py-PEA), which was further treated with toluylene-2,4-diisocyanate (TDI), in different weight percentages to develop a series of pyridine poly(urethane esteramide) resins (Py-UPEA). The structural elucidation of Py-PEA and Py-UPEA were carried out by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. Physico-chemical characterizations of these resins were performed by standard laboratory methods. Thermal analyses of these resins were accomplished by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Coatings of Py-UPEA were prepared on mild steel strips to evaluate their physico-mechanical and chemical/corrosion resistance performances under various corrosive environments. It was found that among all these systems, the sample having 14 wt% loading of TDI showed the best physico-mechanical and corrosion resistance performances. Thermal stability performance suggest that the system could be safely used up to 200 °C. [ABSTRACT FROM AUTHOR]

Abstract: For the first time the synthesis of zinc containing linseed oil based polyesteramide resins (Zn-LPEA-1 to Zn-LPERA-5) with different loadings of zinc acetate were carried out by in situ condensation polymerization reaction between linseed oil derived linseed fattyamide diol (HELA), phthalic anhydride and zinc acetate (divalent metal salt, different mole ratios) in the absence of any solvent. By-products such as water and acetic acid were removed by the application of vacuum technique. This approach was employed to overcome the use of volatile organic solvents [VOCs] during processing and application of the resin, that are ecologically harmful. The structure of the resin was confirmed by FT IR, 1H NMR and 13C NMR spectral studies. Physico-chemical properties were studied by standard methods. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) was used to measure the thermal behaviour of the resin. The antibacterial studies of Zn-LPEA resins were carried out by agar diffusion method. Antibacterial activities of Zn-LPEA were compared with reported virgin linseed polyesteramide (LPEA) and zinc incorporated petroleum based polymers. [Copyright &y& Elsevier]

Abstract: Cd and Zn metal (with completely filled ‘d’ orbital) incorporated linseed oil polyesteramides [Zn-LPEA and Cd-LPEA] were synthesized by in situ condensation polymerization reaction between linseed fattyamide diol (HELA), phthalic anhydride and divalent cadmium/zinc acetate (different mole ratios) obviating the use of any solvent. The structures of these resins were confirmed by FT-IR, 1H NMR and 13C NMR spectral studies. The solubility of the resin was checked in different polar and non-polar solvents. The physico-chemical and physico-mechanical properties were studied by standard methods. Curing and thermal behavior were investigated by DSC and TGA techniques. The corrosion protective performance of coatings on mild steel strips was investigated by standard methods. Agar diffusion method was used to determine the antibacterial activities of these polymers. The studies revealed that the minor incorporation of divalent cadmium and zinc in virgin linseed oil based polyesteramide [LPEA] enhances the physico-mechanical and anticorrosive properties as well as reduces the curing temperature. Besides these properties they also show effective antibacterial behaviour against the Escherichia coli and Staphylococcus aureus. The Zn-LPEA and Cd-LPEA resins are, therefore, inexpensive coatings material, developed from renewable resource, for anti-corrosive and antibacterial applications. [Copyright &y& Elsevier]

Melamine modified polyester amide (MPEA) was synthesized by the reaction of linseed oil fatty amide. The resin was further cured at room temperature by polystyrene co‐maleic anhydride (SMA) in different phr (30–80) to obtain MPEA coatings. The probable structure of MPEA was confirmed by FT‐IR, 1 H‐NMR and 13 C‐NMR spectroscopic techniques. The physico‐chemical characterization of these resins viz. iodine value, saponification value, refractive index, inherent viscosity were carried out by standard methods. MPEA (40 wt%) solution in ethylene glycol monomethyl ether (EGME) was applied on a mild steel strip of standard sizes to study their physico‐mechanical and chemical resistance properties. It was found that coatings of MPEA with 60 parts per hundred of the resin (phr) of SMA showed the best performance in physico‐mechanical and alkali resistance properties. Thermal stability and curing behavior were studied by Thermo Gravimetric Analyses (TGA) and Differential Scanning Calorimetry (DSC), respectively. [ABSTRACT FROM AUTHOR]

Air drying polyesteramide resins (APEAPh) were synthesized by minor incorporations of phthalic anhydride (PA) in poly(styrene-co-maleic anhydride) [SMA] based ambient cured polyesteramide (APEA); the latter prepared by the condensation reaction between N,N-bis(2-hydroxy ethyl) linseed oil fatty amide [HELA] and SMA copolymer in the presence of acid catalyst. The physico-chemical characterization like hydroxyl value, iodine value, saponification value, refractive index and inherent viscosity as well as solubility in different organic solvents were carried out by standard methods. The structure elucidation of the polymeric resin is based on FTIR, 1H NMR and 13C NMR spectroscopic analysis. The thermal stability behaviour was studied by TGA and DSC techniques. The coatings of 70 ± 5μm thickness were prepared on mild steel strips of standard size by brush technique. The scratch hardness, impact resistance, bend test, specular gloss and corrosion resistance test of these coatings show that the presence of phthalic anhydride considerably enhances the physico-mechanical and corrosion resistance performance of APEAPh as compared to those of APEA coatings. [Copyright &y& Elsevier]