Value addition to waterborne polyurethane resin by silicone modification for developing high performance coating on aluminum alloy

Silicone-polyurethane waterborne coatings were synthesized using sol-gel technique for protecting aluminum and its alloys. These are derived using polyurethane (PU), hexamethoxymethylmetamine (HMMM) and silicones Such as methyltrimethoxysilane (MTMS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) as precursors. Structural and morphological features of coatings were assessed using Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Performance of the coatings was evaluated using potentiodynamic polarization studies, contact angle measurement, DSC/TGA. UV-vis spectrophotometer, and mechanical tests such as flexibility, pencil hardness test and impact resistance. (C) 2008 Elsevier B.V. All rights reserved.