The surface coating industry is globally involved in developing useful, eco-friendly, and VOC (volatile organic compounds)-free coating systems, which exhibit promising physico-mechanical and corrosion protective performance. Herein, we report the synthesis of butylated melamine formaldehyde (BMF)-modified soy alkyd (SA-BMF). The structural elucidation and molecular weight of soy alkyd (SA) and SA-BMF resin was carried out by FT-IR, 1 H NMR, and 13 C NMR spectroscopy and gel permeation chromatography (GPC) techniques. The physico-chemical and physico-mechanical properties were tested by standard protocols. Initial decomposition temperature was measured by thermogravimetric analysis (TGA). The curing study and glass transition temperature were assessed by differential scanning calorimetry (DSC). Hydrophobicity of the coatings was measured in terms of contact angle. The anticorrosion performance of SA-BMF was studied experimentally using polarization techniques and electrochemical impedance spectroscopy (EIS), while the antimicrobial efficacy of the same were tested against Gram positive bacterium Staphylococcus aureus (S. aureus) and Gram negative bacterium Escherichia coli (E. coli) by the agar diffusion method. Overall, our studies revealed that the waterborne SA-BMF coating exhibited higher scratch resistance, impact resistance (150 lb/in.), and bend tests (flexibility retentive 1/8 in.), along with good antibacterial activity and anticorrosive performance. These coatings also find safe usage up to 200°C.

The sustainable resource based volatile organic content (VOC) free coatings with superior anticorrosive properties are some of the most in demand in the surface coating industry. In the present investigation, we report the synthesis of butylated melamine formaldehyde (BMF) cured waterborne castor alkyd (WCA-BMF) using environmentally friendly solvent for anticorrosion applications. The cured resin was characterized by spectroscopic techniques, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The molecular weight of the resin was determined by gel permeation chromatography (GPC). The corrosion protection performance of the coatings on carbon steel strips (CS) was investigated by potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and the salt spray test. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) examinations were carried out to study the morphology of bare CS and coated CS before and after exposure to a salt spray chamber. The results showed the prominent role played by the amount of BMF in the performance of the castor alkyd, as reflected by the high thermal stability, good adhesion, bending ability (1/8 inch bend test), impact resistance (>100 cm), scratch hardness (7.50 kg), along with good hydrophobicity and high corrosion protection performance. Thus, this study revealed that the presence of the s-triazine moiety in waterborne castor alkyd can produce a high performance corrosion protection coating material via a green route.

High-performance vegetable oil based organic–inorganic bio hybrid materials are of great interest in the current scenario, as the utilization of vegetable oil meets the seventh principle out of the 12 Principles of Green Chemistry that contributes to sustainability in chemistry due to their universal availability, inherent biodegradability, low price, and superb environmental credentials. Here, we report the synthesis of transparent organic–inorganic bio hybrid coatings by tailoring the properties of both linseed oil and 3 isocynatopropyl triethoxysilane (IPTES) using the sol–gel technique. Such materials combine the advantages of both the phases that are usually not compatible within the same material (robustness and homogeneity, mechanical strength, flexibility, optical transparency, hydrophobicity, and anticorrosive properties). The structure elucidation, particle size, and morphology of the synthesized OIH polymers were done by FT-IR, 1H NMR, 13C NMR, 29Si NMR, and electron microscopy techniques (TEM and SEM with EDAX). Thermal properties were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. The corrosion resistance behavior of hybrid coatings applied on carbon steel (CS) was evaluated using different electrochemical techniques in 3.5 wt % HCl and NaOH medium. The synthesized hybrid sol–gel material exhibited high transparency in the visible range along with good mechanical, thermal, hydrophobicity, and anticorrosive properties. The results suggest that the biobased hybrid nanocomposite coatings have a great potential to replace the petro-based polymeric coatings for industrial applications.

Magnetic graphene quantum dots have been designed for sensing arsenic in contaminated water based on aggregation induced photoluminescence phenomenon.

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