Search results

To evaluate the performance of the blends of Mesua ferrea L. seed oil based polyurethane resins with a commercially available bisphenol‐A epoxy resin at different weight ratios.

For effective improvement of their various properties, polyurethane‐ester (PE) and polyurethane‐amide (PA) resins of Mesua ferrea L. seed oil were blended with a commercially available bisphenol‐A‐based epoxy (EP) in different ratios (PE or PA:EP = 100:40, 100:50 and 100:60 by weight) by using the solution blending technique in xylene. The tensile strength, impact strength, adhesive strength, flexibility, hardness, elongation at break, swelling behaviour and chemical resistance in different media of the films for both the blends have been studied.

The blending of PE and PA resins of Mesua ferrea L. seed oil with a commercially available bisphenol‐A‐based epoxy (EP) showed very good compatibility of the components as observed by SEM study. The blending also significantly improved the performance characteristics such as drying time, tensile strength, impact strength, adhesive strength, chemical resistance, etc. of the films.

The epoxy resin and the hardener are used of a particular grade of a particular manufacturer. Further, it could be obtained from different sources and of different grades. In addition, the performance characteristics could also be studied to optimise the exact blend ratio.

The method developed provided a simple and practical solution to improve the performance characteristic of polyurethane resin with less than one NCO/OH ratio.

The method for improving the performance characteristics of epoxy modified vegetable oil based polyurethane is something novel and could find numerous applications in surface coatings, adhesive and thin film.

The primary purpose of this work is to prepare the renewable source-based polyurethanes coatings which can be used to substitute petroleum-based materials. In the secondary purpose, the paper included improvement in the properties of said PU coatings using modified nano TiO₂ for industrial PU coatings.

The authors have synthesised low molecular weight polyols (monoglycerides) based on vegetable oils such as castor, linseed, coconut, mustard, sunflower and rice bran oils. These monoglycerides were successfully utilised in the preparation of polyurethane coatings. In order to improve the performance of these coatings, modified nano TiO₂ was incorporated into them. The particle size of TiO₂ was determined by transmission electron microscopy. Coatings prepared were characterised for their properties such as gloss, scratch resistance, impact resistance, flexibility, cross cut adhesion and chemical resistance. The thermal stability of coatings was also studied by thermo gravimetric analyzer.

The polyurethane coatings prepared from six monoglycerides of different oils with polymeric diphenyl methane diisocyanate showed good chemical resistance and thermal stability. Coating properties like impact resistance, flexibility and adhesion were excellent for all of the prepared samples of PU coatings. PU coatings with excellent hardness up to 5B were found with the modification of nano TiO₂ by silane coupling agent. The authors successfully prepared the renewable source-based (monoglycerides of oil) PU coatings.

Practically the authors are able to convert renewable source that is vegetable oils into polyurethane coatings which may have strong potential to be used as industrial surface coating. The properties of the PU coatings were evaluated before and after the incorporation of different concentration of surface-modified nano TiO₂ which revealed that the presence of 1 percent nano TiO₂ showed significant enhancement in coating properties.

The beauty of this work includes synthesis of polyurethanes coatings from renewable source material (monoglycerides of vegetable oils) to substitute petroleum-based materials. The incorporation of silane-modified TiO₂ nanoparticles in renewable source-based PU coatings is another originality of the work. This article is also representing comparative study of various vegetable oils on PU coatings.

This study aims to synthesize pigment and resin from agro-wastes and use them in the formulation of eco-friendly surface coatings.

The pigments and resin were synthesized through a chemical modification of agro-wastes. The pigments were characterized by infrared spectroscopy (FTIR) and were screened for their antimicrobial activities. The physicochemical characteristics of the cashew nutshell liquid (CNSL)-modified resin were evaluated. These precursors and other natural additives were used to formulate surface coatings, and their drying and adhesive properties were evaluated using international testing methods.

It was observed that the curing of the CNSL-modified resin depended on time and temperature. The pigments exhibited antimicrobial activity against E. coli and S. aureus and had high melting points, affirming their stability. The chemically modified precursors successfully yielded surface coatings with acceptable drying times and adhesion to the base substrate.

The use of agro-wastes as the main components of the surface coatings implies waste valorization, a reduction in production costs and the creation of job opportunities for sustainable development. To increase the chemical, physical, corrosion resistance and antimicrobial qualities of paint compositions, chemically modified peanut skin extracts and CNSL can be used as pigments and resins, respectively. This could be a green approach to achieving the targets of Sustainable development goals 11 and 12.

The paper outlines a prospective approach to use unwanted waste (peanut skin, cashew nutshells) and other natural additives as industrial raw materials. These novel surface coating precursors are cost-effective, readily available, eco-friendly and could replace conventional precursors.

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.

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.

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.

The modified PEA compounds can be used as binder in paint formulations to improve chemical, physical and corrosion resistance properties.

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.

This paper aims to prepare a new modified poly(ester amide) (PEA) resins and use it as a binder for anticorrosive and antimicrobial coatings.

New modified PEA compositions were prepared based on 4-amino-N, N-bis(2-hydroxyethyl) benzamide (AHEB) as the ingredient source of the polyol used and evaluated as vehicles for surface coating. The structure of the modifier and PEA resin was confirmed by FT-IR, H¹-NMR, MW, thermogravimetric analysis and scanning electron microscope 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.

The tests carried out revealed that the modified PEA based on AHEB enhanced both phyisco-mechanical and chemical properties. Also, the resins were incorporated within primer formulations and evaluated as anti-corrosive and antimicrobial single coatings. The results illustrate that the introduction of AHEB, within the resin structure, improved the film performance and enhances the corrosion resistance and antimicrobial activity performance of PEA resins.

The modified PEA compounds can be used as binders in paint formulations to improve the chemical, physical, corrosion resistance and antimicrobial activity properties.

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 and antimicrobial 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.

The purpose of this study is to develop poly(etherfattyamide) coatings from Pongamia glabra seeds oil utilizing a sustainable resource, which is non edible, non medicinal and goes as waste. Seed oil based poly(etherfattyamide) is used as a coating material to improve the coating properties especially gloss and alkali resistance.

Pongamia glabra oil was first converted into N,N′ bis 2‐hydroxyethyl Pongamia glabra oil fatty amide (HEPFA). HEPFA was treated with 1,4‐cyclohexanedimethanol (CHDM) to develop poly(etherfattyamide) (PEFA). PEFA was cured with (butylated melamine formaldehyde) (BMF) in different (35, 40, 45, 50) phr (part per hundred part of resin) to produce coating material. The structural elucidations of HEPFA and PEFA were carried out by FT‐IR, ¹H‐NMR and ¹³C‐NMR spectral techniques. The thermal study was performed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The physico‐mechanical and chemical resistance/anticorrosive properties were investigated by standard laboratory methods.

The authors developed a good coatings material from a sustainable resource. The physico‐mechanical and anticorrosive performance evaluation exhibits satisfactory results. PEFA‐BMF coatings material showed good alkali resistance and high gloss. The thermal studies showed that PEFA‐BMF45 may be safely used up to 225°C.

BMF modified PEFA coatings showed the highest scratch hardness 3.5 kg, flexibility (1/8 inch conical mandrel bend test) and gloss at 45° is 76‐82. Among all, PEFA‐BMF45 showed the best physico‐mechanical and chemical resistance performance. Thus, it may be used as an efficient coating material.

The synthesis of BMF modified PEFA from Pongamia glabra oil using 1,4‐cyclohexanedimethanol has been studied for the first time providing a new approach to utilize a non edible seed oil – a sustainable resource.

The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion.

The polyisocyanate aqueous dispersion was synthesized through non-ionic and anionic hydrophilic modification procedures. The values of the hydrogen bonding index (HBI) and molecule structures of WPU were obtained by Fourier transform infrared (FTIR). The thermal, mechanical and water resistance properties of 2K-WPU films were investigated.

The appearance of non-ionic polyisocyanate aqueous dispersion and anionic polyisocyanate aqueous dispersion was colorless translucent pan blue and yellow opaque emulsions, respectively. FTIR not only showed that 2K-WPU was obtained from the polymerization of polyisocyanate component and polyhydroxy component by polymerization but also showed that the content of hydrogen bondings of anionic 2K-WPU (WPU 2) was higher than non-ionic 2K-WPU (WPU 1). The glass-transition temperature (Tg), storage modulus and water resistance of WPU 2 were higher than WPU1, whereas the thermal stability of WPU1 was better than WPU 2.

The investigation established a method to prepare a series of 2K-WPU which was composed of non-ionic or anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. The prepared 2K-WPU film could be applied as substrate resin material in the field of waterborne coating.

The paper established a method to synthesize a series of 2K-WPU. The effect of HBI value and the molecule structure of soft segment on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

Poly(ethylene terephthalate) (PET) waste from soft drink bottles was incorporated into palm olein alkyd to produce new polyol for use in polyurethane resins as surface protection on metal surfaces.

Alkyd was prepared from palm olein, glycerol and phthalic anhydride. PET underwent simultaneous glycolysis and transesterification reactions with the alkyd. Varying the amount of PET has led to polyols with different viscosities. Polyurethane resins were produced by reacting the polyols with toluene diisocyanate. The resins were coated on mild steel panels and cured. Performances of the cured films were tested.

The polyurethanes (PU) resin cured to a harder film with better thermal stability. Films showed excellent adhesion properties, while higher content of PET exhibited higher pencil hardness, better water, salt, acid and alkali resistance.

Other vegetable oils could also be used. The alkyd structure could be changed by formulation to have different functionality and the ability to incorporate higher amount of PET waste. Rate of glycolysis of PET could be increased by higher amount of ethylene glycol.

This method has managed to use waste PET in producing new polyol and PU resins. The cured films exhibit good mechanical and chemical properties, as well as excellent adhesion and thermal stability.

The non-biodegradable PET has created environmental pollution problems connected to littering and illegal landfilling. It has become necessary to pay greater attention to recycling PET bottles for obtaining valuable products.

This approach is different from the earlier reports, where PET was recycled to recover the raw materials.

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.

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.

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.

This paper provides the development of protective coatings for steel from non-edible seed oil and TA to utilize sustainable resources.

The present study aims to demonstrate the use of renewable source in the preparation of polyurethane (PU) coatings and mitigation of corrosion of mild steel using nano zinc phosphate. Results indicated improvement in the properties of the PU coatings, especially anticorrosive properties by the addition of nano zinc phosphate.

Renewable-source-based polyestermyristamide polyol was synthesized using myristic acid as a starting material. The synthesis of polyol was carried by amidation as well as by esterification by a one-pot route. The structure of the prepared polyestermyristamide was confirmed with the support of end-group analysis and spectral study. PU coatings were prepared from synthesized polyestermyristamide polyol and used to protect metal substrate against corrosion. Corrosion properties of the prepared PU were found to be lower; hence, to improve the performance of these coatings, nano zinc phosphate was added to the coatings. The nano zinc phosphate was synthesized in the laboratory by reported sonication method and analyzed for morphology by scanning electron microscopy. Performance of coatings was studied with respect to effect of percentage nano zinc phosphate on thermal stability, mechanical properties and chemical resistances of PU coatings.

The combination of zinc phosphate nano rods and particles in myristic acid-based PU coatings provided substantial corrosion barrier properties to the coatings. Different per cent of the synthesized zinc phosphate nano rods and particles were loaded into the matrix, and corresponding coatings were estimated for corrosion resistance, thermal and chemical properties. Immersion study of the coated panels in 3.5 per cent NaCl solution showed good corrosion resistance for both PU coatings containing 2 and 3 per cent nano zinc phosphate.

This paper has provided the solution to replace existing petroleum-based raw materials with myristic acid as a renewable source in preparing PU coatings. Conventional coatings act as physical barriers against aggressive species but do not have ability to perform as permanent impassable to corrosive species. Hence, nano-sized zinc phosphate is used as corrosion inhibitor in to the synthesized PU coatings for enhancing anticorrosive performance.

In the paper, polyesteramide polyol is synthesized using renewable-source-based material, i.e. myristic acid to replace existing petroleum-based acid as a greener approach. Normally, vegetable oils are preferred as they have such kinds of polyols. The polyesteramide reaction is one pot that avoids the extra steps required in the synthesis. Further, it has been found that the pristine renewable coatings are unable to fully protect subtract from corrosion, whereas an addition of the nano-size zinc phosphate has enhanced the corrosion properties of the coatings.