Print version ISSN 0104-1428
BISCARO, Rogério S. et al. Rheological Study of Paints Based on Polyurethane and PAni-DBSA and its Application as Microwave Absorbing Materials (8 - 12 GHz). Polímeros [online]. 2002, vol.12, n.4, pp. 318-327. ISSN 0104-1428. http://dx.doi.org/10.1590/S0104-14282002000400016.
In this work, conducting paints based on blends of polyurethane and polyaniline in different proportions were prepared. The effects of both, polyaniline doping method and the blend processing time on the paint rheological behavior were evaluated. It was observed that the doping of the polyaniline with dodecylbenzene sulphonic acid (DBSA) by reactive processing (PAni-DBSA-pr) altered the paint complex viscosity due to the excess of the DBSA used in that doping process. This effect was observed during the rheological analyses by controlling the resting time of the prepared samples. FTIR analyses were carried out to verify possible interactions among the components of the mixture (polyurethane and polyaniline), suggesting that no chemical reactions occurred, but only physical interactions. It was also observed that samples containing 15% (w/w) of PAni-DBSA-pr attenuated nearly 48% of the incident electromagnetic radiation, at around 1112 GHz, showing the applying potential of this paint as radar absorbing material.
Keywords : Microwave absorbing materials; conducting coating; polyaniline; polyurethane; rheology; FTIR.