Functional antimicrobial, anticorrosive and sustainable polyurethane composite coatings
A present investigation reports the preparation of polyesteramide polyol (PEA-RIC) from renewable sources like algae oil and ricinoleic acid from castor oil.
It was characterised by 1H NMR and FT-IR spectroscopic techniques, while molecular weight was determined by size exclusion chromatography. Silver doped hydroxyapatite nanoparticles (Ag-HAP NPs) prepared using waste chicken egg-shells were incorporated uniformly in PEA-RIC and their morphology was studied by scanning electron microscopy. Polyol containing Ag-HAP NPs was cross linked using diisocyanate to obtain polyurethane (PU) nanocomposite coatings. Their anticorrosion performance was studied by potentiodynamic polarisation (PDP) method while antibacterial activity was measured against Gram-negative (E. coli) and positive (S. aureus) bacteria.
Nanocomposite coatings with good resistance to bacterial adhesion and bio-film formation
These nanocomposite coatings on metallic substrate inhibited both bacteria when checked by turbidimetric method and interestingly exhibited good resistance to bacterial adhesion and bio-film formation as evidenced by SEM analysis. These coatings showed improved hydrophobicity, adhesion, anticorrosive properties and chemical resistance as compared to PU without nanoparticles. Thermal stability and Tg were found to improve with increasing concentration of Ag-HAP NPs when checked by TGA and DSC. Such coating originating from renewable materials exhibits high applicability in curbing the losses due to corrosion and assists sustainable development.
The study is published in: Progress in Organic Coatings Volume 128, March 2019, Pages 127-136.
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