Fully Biobased Nanocomposites of Hyperbranched-Polyol and Hydroxyapatite in Coating Applications

Abstract

Generally, the coating properties of polymeric compounds are enhanced by using nanomaterials as fillers which are non-biobased. In this project, the hydroxyapatite (HAP) was obtained from waste fish scales and the biobased hyperbranched polyol (HyBP) was synthesized from castor oil. The series of nanocomposites were prepared by adding various amounts of HAP (0.5% wt, 1% wt, and 2% wt) in HyBP along with isophorone diisocyanate (IPDI) (maintaining the NCO:OH, ratio at 1.2:1). These mixtures were coated on mild steel panels and glass plates. The synthesized HyBP was characterized by FTIR, 1HNMR, and 13CNMR techniques. The HAP was characterized by FTIR, FESEM, and XRD techniques. The surface morphology of prepared nanocomposites was studied by FESEM, XRD, and AFM techniques. The nanoparticle size was determined by TEM technique. The thermal behavior of nanocomposites was studied by TGA technique. The coating properties were determined by impact strength, crosscut adhesion, and flexibility test. The corrosion properties of the coatings were determined by the immersion test as well as electrochemical test.