2016 CAN Awards

PROJECT: Development and Characterization of a New Hybrid Polymer-Nanoparticle Composite Coating for Corrosion Protection in Aerospace Applications
PI: Lei Zhang, Assistant Professor, UAF

Much effort has been expended to develop coatings to replace toxic and environmentally hazardous chromates used as pretreatments and pigments in aircraft coating systems. There have also been many claims for chromate replacement in primer or pretreatment for aircraft, even though few functioning systems that can meet specifications are presently in use. Polymer nanocomposite coatings (PNCCs), which use nanoparticles as fillers in polymeric resins, possess synergistic properties of the nanoparticles (electronic, catalytic, and optical) and polymers (glass transition, flexibility, and processability). Because of this unique feature, PNCCs have potential to meet the demand in replacing chromate coatings. The properties of PNCCs are greatly determined by the degree of nanoparticle dispersion within the polymer, which is a key to improvement of mechanical and barrier properties in nanocomposite coatings over those of pure polymer coatings. In particular, PNCCs with extremely high concentrations of nanoparticle fillers are promising coatings for corrosion protection in various applications. However, it is still technically challenging to prepare uniform PNCCs with high loadings of nanoparticles, because a high loading of nanoparticles tends to aggregate in an uncured and viscous polymer matrix. This problem is especially exacerbated when mixing with non-spherical nanoparticle fillers, even after reducing the viscosity of polymer at an elevated temperature.