Nitrogen rich hyperbranched polyurethane‐carbon nanohorn composite: Implications on the development of multifunctional coatings

In the present report, we demonstrate the advantages associated with a multifaceted coating comprising of single‐walled carbon nanohorns (SWNH) and hyperbranched polyurethane (HBPU). To synthesize the HBPU, we utilized sebacic acid and triethanolamine as starting materials employing traditional polycondensation reaction; A₃ + B₄ approach. The degree of branching as estimated from NMR was found to be ∼60%, indicating a good branching profile. Prepared nitrogen rich HBPU coatings exhibited good corrosion resistance and adhesion to the substrate. Furthermore, an in situ blend of pyrene and functionalized carbon nanohorns (f‐SWNH) were introduced within the HBPU matrix to impart additional properties. The obtained HBPU‐SWNH composites (CNH‐PU) exhibited superior storage modulus (∼1081 MPa), lower corrosion rate (6.16 × 10⁻⁵ mm/year), excellent flexibility, and exceptional thermo‐mechanical properties along with fluorescence (due to pyrene moiety). The properties displayed by the composite coatings were much higher as compared to the HBPU in the absence of synergism. POLYM. COMPOS., 39:E772–E779, 2018. © 2016 Society of Plastics Engineers