Studies on a newly developed linseed oil‐based alumina‐filled polyesteramide anticorrosive coating

Polyesteramide (PEA) and alumina‐filled polyesteramide (APEA) resins were synthesized from N,N′‐bis(2 hydroxyethyl) linseed amide. The FTIR, ¹H‐NMR, DSC, TGA, thermal curing, and physico‐chemical characterization of these polymers were carried out. The coatings of PEA and APEA were made on mild steel strips. The mechanical behavior and protective efficiency of these coatings in acid, alkali, and organic solvents were investigated. APEA coatings have been found to show superior performance in comparison to other coatings. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1679–1687, 1999     

Studies on poly(styrene‐co‐maleic anhydride)‐modified polyesteramide‐based anticorrosive coatings synthesized from a sustainable resource

Polyesteramide (PEA) coating resin, synthesized from linseed oil, a sustainable resource, was found to show improved physicomechanical and acid‐resistance properties. To further improve these properties in terms of alkali resistance, scratch hardness, and thermal stability and to reduce the baking temperature, we have attempted to incorporate styrene into the polymer backbone through its copolymer with maleic anhydride. The structural elucidation of modified PEA resin (SCPEA) was carried out by FTIR, ¹H‐NMR, and ¹³C‐NMR spectroscopes. The physicomechanical and chemical‐resistance properties were investigated by standard methods and thermal stability was investigated by thermogravimetric analysis method. A comparative study of these properties of PEA and SCPEA was carried out. It was observed that the SCPEA showed better properties than the reported one. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2538–2544, 2004     

Studies on urethane‐modified alumina‐filled polyesteramide anticorrosive coatings cured at ambient temperature

Coatings prepared from polyesteramide resin synthesized from linseed oil, a renewable resource, have been found to show improved physicomechanical and anticorrosive characteristics. These properties are further improved when aluminum is incorporated in the polyesteramide resin. The coatings of this resin are generally obtained by baking at elevated temperatures. With a view toward the use of linseed oil, as a precursor for the synthesis of polyesteramide resins and to cure their coatings at ambient temperature, toluylene diisocyanate (TDI) was incorporated into polyesteramide and alumina‐filled polyesteramide in varying proportions to obtain urethane‐modified resins. The latter resins were found to cure at room temperature. The broad structural features of the urethane‐modified polyesteramide and alumina‐filled polyesteramide were confirmed by FTIR and ¹H–NMR spectroscopies. Scratch hardness; impact resistance; bending resistance; specular gloss; and resistance to acid, alkali, and organic solvents of the coatings of these resins were determined by standard methods. Physicomechanical and anticorrosive properties, specular gloss, and thermal stability of the urethane‐modified alumina‐filled polyesteramide coatings were found to be at higher levels among these resins. It was found that TDI could be incorporated in polyesteramide up to only 6 wt %, such that above this loading its properties started to deteriorate, whereas alumina‐filled polyesteramide could take up to 10 wt % TDI. Explanation is provided for the increase in scratch hardness and impact resistance above 6 and 10 wt % addition of TDI in polyesteramide and alumina‐filled polyesteramide, respectively, as well as for the decrease in flexibility and resistance to solvents, acid, and alkali of coatings of these resins above these limits of TDI addition. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1855–1865, 2001     

Synthesis and characterization of poly(esteramide‐urethane) from linseed oil as anticorrosive coatings

Ethylene diamine polyesteramide (Ed‐PEA) was synthesized from N, N‐bis (2‐hydroxy ethyl) linseed oil fattyamide and ethylene diamine tetra acetic acid through condensation polymerization. It was further treated with toluylene 2,4‐diisocyanate (TDI) in different weight percentage to obtain urethane‐modified polyesteramide (Ed‐UPEA). The structural elucidation of Ed‐PEA and Ed‐UPEA were carried out by FTIR, ¹H‐NMR, and ¹³C‐NMR spectroscopic techniques. Thermal studies of these resins were carried by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The coatings of urethane‐modified polyesteramide were prepared on mild steel strips and their anticorrosive behavior of in acid, alkali, water, and xylene were investigated. Thermal stability performance suggests that the system could be safely used upto 200°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Water‐borne melamine–formaldehyde‐cured epoxy–acrylate corrosion resistant coatings

Organic protective coatings are widely used in corrosion control. However, environmental standards establish that the volatile organic compounds either must be removed or controlled at the lowest possible levels. The carcinogenic environmental impact of volatile organic compounds has led to the substitution of solvent‐borne coatings by water‐borne coating systems. Among recently developed water‐borne coatings, epoxy‐ and acrylic‐based coatings have a special significance over other reported water‐borne systems. Keeping in mind, the importance of water‐borne coatings in the present work, we report the synthesis of water‐borne epoxy–acrylate (EpAc) and melamine–formaldehyde (MF) as well as formulation of their anticorrosive coatings. The structural elucidation of MF‐cured EpAc was carried out by FTIR, ¹H NMR, and ¹³C NMR spectroscopic techniques. The coatings of EpAc‐MF were applied on mild steel strips and were evaluated for physicochemical, physicomechanical characterization, and the anticorrosive performance under different environmental conditions. The present coating system EpAc coatings exhibited superior performance as compared to the reported water‐borne epoxy–acrylatecoatings. The presence of melamine–formaldehyde in the resin increases the scratch hardness, impact resistance, alkali resistance, and thermal stability of these coatings. EpAc‐MF‐1 was found to cure at ambient temperature and exhibit good physicomechanical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

In situ development of Zn/Cd‐incorporated poly(esteramide‐urethane) from sustainable resource

It was for the first time we attempted to develop zinc and cadmium incorporated linseed oil based poly(esteramide‐urethane) [Zn/Cd‐LPEAUr], and investigated their structure, mechanism, and properties. The resin was synthesized in situ by the reaction of linseed oil derived fatty amide diol [HELA], divalent zinc/cadmium acetate and toluylene‐2, 4 (6), diisocyanate [TDI; 2–12 wt %] with minimal solvent. The structural elucidation of Zn/Cd‐LPEAUr was carried out by FTIR, ¹H‐NMR, and ¹³C‐NMR spectral techniques. TGA and DSC techniques were used to measure the thermal stability and curing behavior of these resins, respectively. The physicomechanical and chemical/corrosion resistance properties were investigated by standard laboratory methods. The performance of Zn/Cd‐LPEAUr coating was compared with reported oil based polyesteramide. Antibacterial test of the resins were performed by agar diffusion method against E. coli and S. aureus, and compared with those of petroleum‐based metal containing polyurethanes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Development of linseed oil based polyesteramide without organic solvent at lower temperature

Linseed oil based polyesteramide was synthesized at lower temperature in the absence of organic solvent through condensation polymerization reaction [Sf‐LPEA]. In this reaction N,N‐bis(2‐hydroxyethyl) linseed oil fatty amide and phthalic anhydride were heated at temperature lower than their onset of melting points and the by‐product, such as water was removed by application of vacuum technique. This approach was employed to overcome the use of volatile organic solvents used during processing and application of resin, which are ecologically harmful. The solubility of Sf‐LPEA was checked in different polar and nonpolar solvents. The FTIR, ¹H NMR, and ¹³C NMR spectral techniques were used to confirm the structure of Sf‐LPEA. The physicochemical, physicomechanical, and chemical resistance properties of the resin were investigated by standard methods. DSC and TGA were used to determine, respectively, the curing behavior and thermal stability of the resin. The comparative study of these properties of Sf‐LPEA with reported polyesteramide [LPEA], which are normally synthesized at higher temperature in organic solvent, was done. It was found that Sf‐LPEA exhibited improved physicomechanical, chemical resistance properties, and higher thermal stability compared with LPEA, and hence can find application as corrosion protective coating. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1143–1148, 2007     

Synthesis,characterization, and performance evaluation of hard,anticorrosive coating materials derived from diglycidyl ether of bisphenol A acrylates and methacrylates

Diglycidyl ether of bisphenol A acrylate (DAC) and diglycidyl ether of bisphenol A methacrylate (DMAC) were synthesized by the reaction of an epoxy [diglycidyl ether of bisphenol A (DGEBA)] with acrylic acid and methacrylic acid, respectively. The synthesized resins were characterized by determination of the acid, hydroxyl, and saponification values. Structure elucidation was done by gel permeation chromatography, Fourier transform infrared spectroscopy, ¹H‐NMR spectroscopy, and ¹³C‐NMR spectroscopy. DACs were cured with melamine formaldehyde resin at low pH values. The pH of the resin systems was adjusted with phosphoric acid. The coatings of these systems were formed on mild steel specimens for physicomechanical and chemical/corrosion‐resistance performance. The coatings of DAC and DMAC showed excellent scratch hardness and good impact‐resistance performance. The coatings of DMAC showed better performance than DAC with respect to chemical and corrosion resistance. Thermogravimetric analysis and differential scanning calorimetry were used to investigate the thermal stability and curing behavior of these systems. DAC showed a little higher glass‐transition temperature than DMAC and also showed a higher thermal resistivity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 494–501, 2005     

Studies on self cured zinc-containing Pongamia glabra oil based polyesteramide

Efforts have been made for the development of high performance protective coating materials from non drying oil such as Pongamia glabra oil and their commercialization. Zn-containing self cured Pongamia glabra oil based polyesteramide [Zn-APGPEA] resin was synthesized in situ by the reaction of Pongamia glabra fatty amide diol [HEPGA], poly(styrene-co-maleic anhydride) [SMA] and zinc acetate (different ratios) at 100 ± 5 °C in the presence of an acid catalyst. The physico-chemical characterizations of the resin were carried out by standard laboratory methods. The structural elucidation of the prepared resin was carried out by FTIR, ¹H NMR and ¹³C NMR spectral techniques. The thermal behavior was studied by TGA technique. Antibacterial activity was measured by agar diffusion method against Escherichia coli and Staphylococcus aureus. The effect of the loading of zinc on properties of Zn-APGPEA film was also investigated. The properties of Zn-APGPEA compared with reported self cured Pongamia glabra polyesteramide [APGPEA]. Physico-mechanical and chemical/corrosion resistance test of Zn-APGPEA coatings showed that the presence of zinc metal in APGPEA considerably enhances the overall film performance and also improves antibacterial activity. Therefore, Zn-APGPEA can be used as an anti-corrosive and antibacterial coatings material which may substitute polymers obtained from petroleum.     

Pongamia glabra seed oil based poly(urethane–fatty amide)

Poly(urethane–fatty amide) (PUPGFA) was developed to use nonedible and nondrying Pongamia glabra seed oil. The resin was synthesized by the reaction of N,N‐bis(2‐hydroxyethyl) P. glabra fatty amide (HEPGFA) and tolylene‐2,4‐diisocyanate through a one‐shot technique with a minimal amount (8–10%) of organic solvent. The structural elucidation of the resin was carried out by Fourier transform infrared (FTIR), ¹H‐NMR, and ¹³C‐NMR spectroscopic techniques, whereas the curing mechanism was confirmed by FTIR spectroscopy and differential scanning calorimetry. The solubility of the resin was studied in different polar and nonpolar solvents. Thermal analysis was carried out by thermogravimetric analysis and differential thermal analysis techniques. Antibacterial studies of HEPGFA and PUPGFA were performed in the presence of Gram‐negative Salmonella and Gram‐positive Staphylococcus aureus bacteria by an agar diffusion method. Physicochemical, physicomechanical, and corrosion‐resistance tests were performed by standard laboratory methods. PUPGFA had good physicomechanical properties, excellent chemical/corrosion resistance, and moderate antibacterial activities. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis,characterization, and anticorrosive coating properties of waterborne interpenetrating polymer network based on epoxy‐acrylic‐oleic acid with butylated melamine formaldehyde

The present study reports the synthesis and characterization of waterborne interpenetrating network (IPN) of epoxy‐acrylic‐oleic acid (EpAcO) with butylated melamine formaldehyde (BMF). The effect of BMF on the formation of IPN was investigated in terms of physicochemical, spectral, morphological, and thermal analyses. The coating properties of the IPN were investigated for their physicomechanical, corrosion resistance, and antimicrobial activity. The formation of the IPN was confirmed by FTIR and ¹H NMR analyses as well as physicochemical properties. The EpAcO‐BMF IPN coatings were found to exhibit far superior corrosion resistance performance and good thermal stability when compared with the reported waterborne epoxy acrylic‐melamine formaldehyde systems [EpAc‐MF]. The preliminary antimicrobial investigations of the IPNs were carried out by agar diffusion method against some bacteria and fungi. The results revealed that antimicrobial activities were enhanced upon the formation of IPN. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Renewable Source Based Non-biodegradable Polyurethane Coatings from Polyesteramide Prepared in One-Pot Using Oleic Acid

The highlight of the work was the preparation of polyesteramide in a one-pot reaction which avoids isolation of diethanol amide as it is normally required in polyesteramide preparation. In the present work, oleic acid was reacted with diethanol amine resulting in diethanol amide which further reacted with phthalic anhydride in the same reaction vessel without isolation and purification. Therefore the reaction is a one-pot, time-saving and cost-effective method as it requires minimum solvent and processing steps. In addition to this, the fatty acid used was a single fatty acid (oleic acid) that provides selective physico- chemical and anticorrosive properties for the resin. FT-IR and ¹H-NMR spectroscopic studies confirmed the structure of the polyesteramide. End group analysis and molecular weight were used to calculate the stoichiometric balance of the NCO/OH ratio in the preparation of polyurethane. The prepared resin was converted to polyurethane coatings by reacting with toluene diisocyanate and methylene diphenyl diisocyanate. Thermal stability, physico-chemical and coating properties of the polyurethane coatings were investigated. The polyurethane prepared showed a non-biodegradable nature so that it is of commercial interest and value for applications in various fields. Study of coatings was also carried out for properties like adhesion, impact resistance, pencil hardness and the bending test.     

Biobased dimer fatty acid containing two pack polyurethane for wood finished coatings

Novel two pack polyurethane wood finished coatings are prepared from renewable sources, such as vegetable oil based fatty acid and dimer fatty acid. In actual experimental part oleic acid was reacted with diethanolamine to obtain amide which was on condensation polymerization with dimer fatty acid converted into the polyesteramide polyol. These are all being used to prepare polyurethanes. The functional and structural elucidation of dimer fatty acid based polyesteramide and diethanolamide were carried out by end group analysis, spectral studies such as FTIR and ¹H NMR. Average molar masses of the polyesteramide were estimated by gel permeation chromatography (GPC). The polyesteramide was used in the preparation of wood finished polyurethane coatings by reacting it with aromatic diisocyanates. Thermogravimetric analysis (TGA) was used to study the thermal behavior of coatings. Physico-chemical and coating properties of the coatings were investigated by using standard methods. The results indicated that the bio-based wood finished PU coatings provided good mechanical, weather resistance as well possessed adequate coating properties for wood surface protections.     

Studies on self cured zinc-containing Pongamia glabra oil based polyesteramide

Efforts have been made for the development of high performance protective coating materials from non drying oil such as Pongamia glabra oil and their commercialization. Zn-containing self cured Pongamia glabra oil based polyesteramide [Zn-APGPEA] resin was synthesized in situ by the reaction of Pongamia glabra fatty amide diol [HEPGA], poly(styrene-co-maleic anhydride) [SMA] and zinc acetate (different ratios) at 100 ± 5 °C in the presence of an acid catalyst. The physico-chemical characterizations of the resin were carried out by standard laboratory methods. The structural elucidation of the prepared resin was carried out by FTIR, ¹H NMR and ¹³C NMR spectral techniques. The thermal behavior was studied by TGA technique. Antibacterial activity was measured by agar diffusion method against Escherichia coli and Staphylococcus aureus. The effect of the loading of zinc on properties of Zn-APGPEA film was also investigated. The properties of Zn-APGPEA compared with reported self cured Pongamia glabra polyesteramide [APGPEA]. Physico-mechanical and chemical/corrosion resistance test of Zn-APGPEA coatings showed that the presence of zinc metal in APGPEA considerably enhances the overall film performance and also improves antibacterial activity. Therefore, Zn-APGPEA can be used as an anti-corrosive and antibacterial coatings material which may substitute polymers obtained from petroleum.     

Studies on blends of melt‐processable liquid crystalline polymers and thermoplastics. I. Blend of polyesteramide with polyethylene

The processability characteristics, physicomechanical properties, and thermal decomposition characteristics of blends of low‐density polyethylene (LDPE) and polyesteramide (PEA), a thermotropic liquid crystalline polymer, were studied using various analytical techniques. Studies on a Brabender Plasticorder at temperatures ranging from 170 to 230°C showed good melt processability for the blends. The melt rheology of the blends containing 0–15% of PEA at 170°C was studied using a capillary rheometer (Goettfert) fitted with a circular die (L/D = 30/1) at apparent shear rates ranging from 12 to 2300 s⁻¹. The samples containing PEA showed a comparatively lower die swell at high shear rates. X‐ray diffraction measurements showed a reduction in crystallinity of LDPE in the presence of 2–4% of PEA. Scanning electron microscopic evaluation of the morphology of the fractured surface of the blend showed some degree of orientation, but not to the level typical of LCPs. However, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicated significant improvement in the resistance to thermooxidative decomposition of LDPE modified with PEA. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1811–1817, 2000     

Preparation and evaluation of a new anti-corrosive coating based on asphalt cement blended with polyesteramide resin for steel protection

Asphalt cement is a material commonly used in coating applications due to its good adhesion properties and relatively low cost. Unfortunately it has the drawback of being slow to dry. Long polyesteramide resin (PEA) is predominantly used for air-dry and force-dry industrial coatings onto metal surfaces, yet is considered to be a relatively weak material. This paper focuses on the potential synergy of mixing asphalt cement, of penetration grade 60/70, with polyesteramide resin to produce industrial coatings for steel applications, with the aim of overcoming the slow drying time of the asphalt cement and the relative weakness of PEA resin. To achieve this aim, PEA resin was mixed with asphalt cement in a range of concentrations from 3 to 12% (w/w). The prepared coating blends were characterised physically using scanning electron microscopy (SEM), while the performance of the coatings were evaluated for mechanical properties and corrosion resistance in selective chemical reagents, following complete immersion for the duration of 84 days. The results obtained concluded that generally, a blend of asphalt cement and polyesteramide resin produces an effective material for industrial coating applications. Also, 9% and 12% PEA resin content produced high-quality anti-corrosive material as compared to virgin asphalt cement. The degree of modification depends upon the properties of the asphalt and the content level of the polyesteramide.     

Synthesis and characterization of new modified anti-corrosive polyesteramide resins incorporated pyromellitimide ring for surface coating

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 ± 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 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.     

Synthesis,formulation, and characterization of siloxane‐modified epoxy‐based anticorrosive paints

Diglycidyl ether of bisphenol A epoxy (E) was modified with hydroxyl‐terminated polydimethylsiloxane through a ring‐opening addition polymerization reaction. The structural elucidation of the siloxane‐modified epoxy resin (ES) was carried out with Fourier transform infrared, ¹H‐NMR, and ¹³C‐NMR spectroscopy techniques. The physicochemical characterization of the synthesized resin (ES) was performed with standard methods. E and ES were subjected to paint formulation with the help of a rutile (TiO₂) pigment. The formulated paint systems were cured at room temperature with 1,6‐diaminohexane (AH) and 1,3‐diaminopropane (AP), which were used as curatives. The E–AH, E–AP, ES–AH, and ES–AP paint systems were applied to mild steel strips. The physicomechanical and anticorrosive performance of the coated panels was evaluated with standard methods. The thermal analysis of these E–amine and ES–amine systems was carried out via thermogravimetric analysis. The effects of siloxane incorporation and amine curatives on the coating properties of the paint systems were also investigated. The ES–AP system exhibited good thermal and corrosion stability performance among all the E and ES paint systems. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4981–4991, 2006     

Synthesis and characterization of novel dendritic poly(ester‐amine) with peripheral hydroxyl

Dendritic poly(ester‐amine) with a peripheral hydroxyl [PEA(OH)] was synthesized from dendritic PEA terminated with acrylic double bonds [PEA(?)] and diethanolamine (DEA) by a Michael addition reaction. The effects of the reaction temperature, time, and solvent on the purities of PEA(OH) were studied. It was found that when the mole ratio of PEA(?) to DEA was 1:8 and the reaction was carried out in methanol at 25°C for 22 h, the purity of PEA(OH) was 94.6%. The structure of PEA(OH) was identified by IR, ¹H‐NMR, and elemental analysis. PEA(OH) is a surfactant and its aqueous form exhibits cloud points between the mass concentrations of 0.1 and 50 mass %. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 60–64, 2005     

Waterborne oil‐modified polyurethane coatings via hybrid miniemulsion polymerization

As part of a wider effort to develop a new class of waterborne coatings, hybrid miniemulsion polymerization was carried out with acrylic monomers (methyl methacrylate, butyl acrylate, and acrylic acid) in the presence of oil‐modified polyurethane resin. Latexes with different ratios of resin to acrylic monomers were synthesized. The monomer emulsions prepared for hybrid miniemulsion polymerization showed excellent shelf‐life stability (>5 months) and the polymerization was run free of coagulation. Solvent extraction indicated that the grafting efficiency of polyacrylics was greater than 29% for all the samples produced. A ¹³C solution NMR spectrum showed that a substantial fraction of the original carbon double bonds (>61%) in oil‐modified polyurethane remained after polymerization for film curing. Films obtained from the latexes presented good adhesion properties and fair hardness properties. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 105–114, 2000